 Are you a photographer that has always wanted to try astrophotography but you weren't so sure about investing hundreds or even thousands of dollars into a hobby before you knew if it was for you? Well then watch this video because I'm going to show you how you can capture and process a photo of the Orion Nebula with gear you might already have. For this tutorial, I'm just going to be using five pieces of gear, a DSLR, a lens, a tripod, an inexpensive intervalometer, and this last one is optional. This is a cheap botanical mask. Hey, if you're new to my channel, welcome. My name is Nico Carver. I'm a DeepSky astrophotographer and my website is nebulaphotos.com. With this channel, I would just want to share my love of astrophotography and especially help newcomers to the hobby get started. And I'll also just mention really briefly here at the start that I do have a Patreon. Thanks so much to everyone who already supports me. It really keeps the channel going at a steady pace. If you're interested, my Patreon starts at just $1 a month. Today I'm going to show you how you can capture DeepSky objects, meaning objects out in space that are outside of our solar system. This tutorial will work for many different DeepSky objects. I'm going to be shooting the constellation Orion, which is setting in the west right now. And we should be able to see after processing the Orion nebula, the horse head nebula, and the flame nebula. And we're going to do it with just five pieces of equipment, a stock DSLR, a fast lens, a tripod, an intervalometer, and a botanical mask. If you've seen my most popular video series, it's called Orion Nebula Start to Finish. This is going to be somewhat similar to that with a little bit of overlap. But the technique and the processing will be different since we're not going to be using a tracker or a telescope as I did in that video series. For those new to astrophotography, what a star tracker does, or when they get a little bit bigger, they're called a mount, an astrophotography mount. What it does is it moves your camera at a constant rate. That rate is called the sidereal rate. So it has a little motor in here with gears. And then it just moves everything on top, called the payload, at the sidereal rate. And that rate, what it is, is it's the rate that the stars seem to move across the sky from our vantage point here on Earth. And you can keep time to it just like we normally keep time with the solar rate. Of course, it's not really the stars moving. They're so far away from us that they're practically fixed. It's really that the Earth is rotating very fast around its axis called the celestial pole. And that's why the stars are seeming to move across the sky. So another way to think of a star tracker or a mount is the device to counteract Earth's rotation. So Earth's rotating this way, the star tracker is going to move in the opposite way at that sidereal rate. And what that allows you to do is take long exposures of the night sky and have sharp stars and bring out those DSO's deep sky objects through long exposure. But they'll remain nice and sharp because you don't get the motion blur from Earth's rotation with the star tracker. But today, we're not going to use the star tracker or a telescope because I want to show everyone out there that you can start doing deep sky astrophotography with gear that's really more just common photography gear, gear you might already have, at least a lot of it. And I'm going to repeat this a lot. Your gear does not have to be the same as mine to follow along with this video. As long as you have some kind of camera that can do some manual exposure control, you have some kind of lens to be better if it can shoot F4 or faster, a tripod, and you have some way of taking many exposures without having to touch the camera each time. Then you have everything you need for this tutorial. First thing I'm going to do is I'm going to talk about each piece of equipment that I'll be using tonight and we'll start with the tripod. First thing I'm going to say, if you already have a tripod, use the tripod you have. For your first time trying astrophotography, there's no need to upgrade anything that you already have. That being said, the sturdier the tripod, the better. I'm a big fan of Manfrotto tripod legs. These are aluminum Manfrotto tripod legs that are probably 15 years old. I'm sure that I bought it used because I just trust in Manfrotto's quality. They have held up really well. All their stuff works really well. But the sturdiness comment and the reliability also goes for the tripod head. You want to use the biggest, sturdiest tripod head you have. And for me right now, that's this video head. It's not designed for astrophotography, but it just has a nice big platform for holding the camera. I know for a fact that when I lock down the tilt or the pan, that those stay in place and can hold a lot of weight. So with the tripod head, bigger the better. If it's a ball head, just make sure that it really stays stable. OK, next piece of equipment is the DSLR. This is an eight-year-old camera. It's my Canon 5D Mark III that I bought the year it came out. It's a very nice full-frame camera. But that really doesn't matter. Just use whatever you have. I've repeated this a number of times now. And the reason is I've often heard people remark, well, I'd like to do astrophotography, but my gear isn't good enough. My camera is not good enough. It's not true. If you have a camera that you can manually control the exposure, you can do this. One other aspect that's really handy, and we're going to be using in this tutorial, is you want your camera to be able to controlled with an intervalometer. So almost any DSLR that you have will do this. If you don't already have one, you might have to look up what kind of intervalometer you might want to get. They look like this. And what it is, is it allows you to take many shots. So I've tried a bunch of different models. I have a fancy wireless one. So the way the wireless one works is the controller is this thing. And then it has a little receiver that goes on top of the camera and plugs in. And then I can control from, I don't know, something like 30 meters away or something like that. It's handy, but not necessary. It's a little bit more expensive to get a wireless one. A wired one works just fine. This is the newer model. I think it's about $30. And they all basically work the same way. So just get which ever one is designed for your camera. For people that are new to this device, all it does is it allows you to trigger the shutter. So normally, we just hit the shutter button on top of the camera, but without touching the camera physically. And the reason that we want to do this is we're taking a long exposure. We don't want to add any vibration shake by touching the camera when we take that exposure. So we can just hit the shutter button right there to take exposures. But what an intervalometer does, in addition to just being able to take a single exposure like that, is to take a sequence of exposures. So what the camera will do is it'll take hundreds of exposures in a row. And the way you do that, all you have to do is program in the sequence right here and press Start. So really easy. I'm going to show you how to use it. If you are still in the fence about buying one of these, if you don't already have one, it's about $30. Keep in mind that these are also super useful for time-lapse photography. But if you're not in the time-lapse, you're also a real cheapskate, and you really don't want to spend the $30, then what I'd recommend instead is just a shutter release cable. So it looks sort of like the intervalometer, except it's smaller. And all it has is the little external cable release. These go for as low as like $10. So the downside to this, of course, is you can't program that sequence. So what you're going to have to do is just get out there and sit in a chair next to your tripod and be careful not to move and just take hundreds of exposures hitting the button each time. Manually. OK, so it's another option. I don't recommend it, though. Last thing I'll say about intervalometers, Canon is a bit weird. They've never put an intervalometer into the actual firmware of the camera, to my knowledge. Maybe in some of their really newer cameras, I haven't followed it too closely, so don't quote me on that. But a lot of camera manufacturers have been doing it for years. And so read your manual or Google it, because you may find out your camera already has a built-in intervalometer, so you don't actually need to spend any money on this. You can just program it right in your camera and have it rip through a sequence of exposures without you touching anything. Next up, we have the lens. And I'll be using this lens. This is a lens that I bought for filmmaking. It's called the Rokinon Sine 1.5. The optics are the exact same as the Rokinon 85 millimeter F1.4, just so you're aware. Again, use whatever lens you have, even if that's your kit lens that came with your camera, use it. If you do have a choice of lenses, though, I would recommend a lens with a focal length of at least, let's say, 50 millimeters, and one that can shoot faster than F4. So what I mean by faster is the number will be smaller, because remember, focal ratio is a division. So F2 is faster than F4, because the aperture is actually bigger, because 1.5 is bigger than 1.4, right? For astrophotography, you really just want that focal ratio to be faster, so you let in more light, more signal, with each exposure. Also for astrophotography is a general rule of thumb. Prime lenses like this one, where they just have a fixed focal length, so this is just an 85 millimeter lens, will perform better than zoom lenses, where they have a range of focal lengths, like a 70 to 200 millimeters. However, that's just a rule of thumb, because I know that every lens is going to perform differently, and some of the Canon L series lenses, which are very expensive zooms, do perform very well for astrophotography. So just take that with a grain of salt. Primes, as a general rule of thumb, will perform better than zooms. The last piece of gear I'll mention, and this one is optional, because I'm also going to show you how to focus without it, is a Batonov mask. And what a Batonov mask is, is it's a manual focusing aid, and the reason I recommend it is stars are one of the trickiest things to nail focus on. And we have to do the focusing manually, even if your lens has autofocus, because typically the camera's firmware that actually controls the lens autofocus system doesn't work on the stars, because it just isn't trained to do that, and there's just not enough light, typically, for it to do it well. So the Batonov mask is a tool for accurately manually focusing on a bright star. And it really, especially with a lens, that star has to be really bright, like one of the few brightest stars in the night sky for this to work at all. The good news, though, this is cheap. This is, I believe, about $10 from Amazon. It's just plastic. It's not going to hold up forever, but it works OK. So if you are interested in buying one, I'll put the links in my description. And the way that you're going to choose one is measure the diameter of your lens shade here, and then just make sure that that falls within the range listed for that Batonov mask. And then it has these little adjuster pins so that it will just fit and be centered right on your lens like that. For people that are watching this that maybe have been doing astrophotography for a while and are interested, I do have a much better Batonov mask for lens-based systems. This is called the Lonely Spec Sharp Star 2. And this is the 100 millimeter addition. But I really only recommend investing in something like this if you're really serious about astrophotography and specifically lens-based astrophotography. And you have a number of different lenses you want to use it on. Otherwise, I just think it's a little bit too expensive, especially if you don't already have a filter holder system to invest in a really nice Batonov mask like this. The reason that it does work better is, I don't know if you can see that, but the pattern is very fine on this. It's actually printed right on this piece of plexiglass. If you compare that to this one, you can see that the pattern is much coarser on this one. And what that means is that this one is a lot more precise when using lower focal lengths than this one. And that's it for gear. There are a few things you're going to want to plan out, though, before leaving the house. So let's go over them. The first thing, and this is something that I often forget to do until the last minute when it's really too late, is charge your camera battery. You need to do this probably an hour or two ahead of time so that it actually has time to charge. And really, you might want to start in the morning because if you have extra batteries, you want to make sure that those extra batteries are charged too. The last thing you want is to get out there, your battery's dead, and then you just are done for the night until you can charge up. All right, the next preparatory step we're going to take is we're going to figure out where we're going to shoot. And so for this, I've pulled up light pollution map.info. And over here on the right-hand side, there's different overlays. And I'm just going to use the latest information here from 2019. In general, I wouldn't trust this completely, but it's a good start, at least. I find that it's a little bit optimistic, especially this VERS survey. If we switch over to the World Atlas survey, you can see that's a lot more pessimistic. And it's probably a little bit more accurate, actually. But it's not quite as detailed as these later surveys, which is helpful too. So anyways, I live right here in Somerville, Massachusetts. And you can see that's in a really bad place for light pollution. It's quite evident if you just step outside and look at the night sky, because only the 10 to 15 brightest stars are even visible. I can see Polaris, but I can't see many of the other stars in the little dipper, for instance. So that gives you an idea for how bad the light pollution is. But I'm a member of an astronomy club. And the astronomy club has an observing field and clubhouse up here, sort of near this Westford, Chelmsford area. So it's quite a bit better skies up there, a few magnitudes better, really. And so this is where I'm going to go to take the shots for this experiment we're doing in this video. If you have a local astronomy club, I would recommend talking to them, consider joining. You might not even have to join just to find out where some good spots are in your area that you can do some astrophotography. You can also just Google around and try to find this information online. But this light pollution map also gives you just a general idea. Another idea I have for you is you can look for parks, especially some state parks might have some open parking areas that you could pull off the road and set up at night. You don't want to get trapped in a park, of course. So just be careful out there. Make sure that you're not getting locked in or something like that. That's happened to me a couple times, but usually it works out OK. So yeah, the idea here is to look for a place that is not one of these brighter hot colors, the red, orange and yellow, but one of these cooler colors, the green and blues and blacks are really the ideal place. If we just zoom out and look at the whole US here, you can see I've lived for the past dozen years or so along the eastern seaboard, which is one of the worst places in terms of light pollution in the US. When you go out here to the west, it's much easier to find a really dark site. Really nothing over here on the eastern seaboard is except if you go up to Maine maybe or down to West Virginia is going to be nearly as dark. Because even when you escape the really bad light pollution, you still have a huge light dome whenever you point your camera from where I am to the south of the east from the city of Boston. So even if you can get out a little bit, you really have to get out quite far to really escape light pollution if you live in a big city. But the point is just try the best you can to get to a darker site, because that's really going to make your photo much better and much easier to process. OK, the next thing is going to get a little bit technical, but I think you can handle it, is we have to figure out the proper exposure length. If you're coming from the photography world, you'll know this is shutter speed. But in astrophotography, since we're typically dealing with long exposures, we don't usually call it shutter speed. We call it just exposure length or sub-exposure length. And let me explain what sub-exposure means or sub for short. You can think of our final processed image as the total exposure, or often called the total integration. And it's a combination of many shorter sub-exposures, because what we're going to do is we're going to stack many sub-exposures together to reduce overall noise in the picture. So what we're trying to calculate right now is actually the length of each sub-exposure. And there's two factors to keep in mind. One, we want to expose as long as possible each sub-exposure to get as much signal hitting the sensor in each sub-exposure. But two, we want to have round stars. And the Earth's rotation is what makes that difficult. That's why we might invest in a star tracker to counteract that. But we're not going to use a star tracker. So we have to figure out how long we can expose for before the Earth's rotation turns our little round stars into eggs, or lines, or arcs, or whatever they're going to be. We want those stars to be round, not misshapen. And finding out that exposure time for round stars, you can just do it with trial and error. So we can get out under the night sky. We can start, let's say, at one second, take a picture, look at it. OK, we got round stars. Let's go to two seconds. Take a picture, look at it. Yep, looks good. Three seconds. Take a picture, look at it. Oh, now they're no longer round stars. I think our maximum exposure time then is going to be two seconds. So that's one way of doing it, trial and error. If you're happy with that, go for that. And you can skip over the next 10 minutes of this video. Because the next 10 minutes, I'm going to talk about formulas for trying to figure out your optimal sub-exposure time. The most famous formula is called the rule of 500. I have a whole video comparing that to the rule we're actually going to use. I'm not going to go into it, but we're not going to use the rule of 500. It's not that great if you're planning to stack your exposures, because for stacking, we really want round stars. And so instead, we're going to use the NPF formula. There are two places you can access the NPF formula. One is free, and the other one is in a paid app. So let's first look at the free one. The free one is on the website of the Société du Havre, where the original developer of the formula, Frédéric Michaud, has a nice calculator. I'll just mention briefly here, the other method is the PhotoPills app. And that app costs $10. So I'd only really recommend buying an app if you know that you're really into astrophotography. But I'm going to show you how to use both tools right now, because maybe some of you might already have the PhotoPills app, but have never used the NPF formula in PhotoPills. But we're going to start here with Frédéric's web calculator. OK, looking at the website here, if you do read French, then you can use it in the original French. But if you don't, then I'd recommend using Google Chrome, because built into Google Chrome browser is the Google Translate. So if I go up to the address bar in the upper right, here's the translate button. And I can click translate this page and choose English. And it does its best job to translate from the French to the English. So that should help a bit to understand the rule and learn something from the page. I'm not going to go through this all, because I want you to read this on your own. One thing that's a little confusing is the changes from the NPF rule to the MFN rule. Not sure why. Anyways, we just go through here, and all the things that we need to fill out are highlighted in this blue. And then when we're done filling that out, the results will be down here in the yellow. So we start with picking our camera brand and then pick the model. So I'm using the 5D Mark III today. Then we're going to put in the information about the lens. So I'm just going to use the example of the lens that we've been talking about, which is the Nifty 50. So it's 50 millimeter focal length and an aperture of four is what I'm going to use. Then this is nice that you don't really have to know the declination of your object. You can just tell it which direction you're shooting. So I'm going to choose Southeast. I'm going to choose my latitude of my location here, which is about 42 degrees. And my target location is about 40 degrees above the horizon. If you don't know these things ahead of time, you can look them up in Stellarium or one of the many planetarium apps. Last thing to choose here is whether we're going to shoot horizontally or vertically. And then we just click calculate the exposure time button and all of the information is down here in the yellow box. And we can see with a rule of 500, we would have a 10 second, which agrees with what we've been talking about. With a simplified NPF rule, we have six and a half seconds. We could round that down to six. And with the complex NPF rule, we have some difference here across the sensor, but basically three seconds. We're going to round down to three. If you keep scrolling down in this page, it explains exactly how he calculated the NPF rule and how he came to the formula, and it explains it very well. So I would definitely recommend reading that all. Again, the author is Frédéric Michaud. And I really like that he took the time to put this together and figure out this formula. So I hope other people find it as useful as I did. So another way to calculate both the NPF rule and the rule of 500 is with an app I found called PhotoPills. I've actually had this app for a while, but didn't realize it did all of this. You can get this app from the App Store. It's available both on Android and iOS devices. And it's currently $9.99 on either App Store. So it's a little bit expensive for an app, but it does a lot more than just help you calculate exposure time. It also has a virtual AR planetarium and all these different cool features built in for planning your astrophotography. So right here on the home screen for PhotoPills, if I scroll down a little bit, one of the tools is called Spot Stars. So I'm just going to click on that. It has a camera database. So I'm gonna search for my camera. I've already chosen the Canon 5D Mark III, but I'm just gonna choose it again here, where they're gonna put in the focal length of the lens. So I'm just gonna use 50 millimeter again. The aperture, I'm gonna use F4. The declination of the object. And it also has an AR mode, which is pretty cool. It puts a planetarium on top of your camera, and then you can just find the object you're looking for in the night sky and set it that way. Then the last thing is it says default or accurate. And what this is, is the default is the simplified MPF rule, and the accurate is the full complex MPF rule. I've looked at this app across many different focal lengths and apertures and declinations and all of that, and these results for both the complex and the simple MPF rule do match up with Frederique Machaud's website. So I feel that you can use photo pills instead of the website. It is very handy to have this sort of mobile app when you're out in the field for calculating the MPF rule and not having to do all that math. And then you can also compare it right below to the rule of 500. Okay, now that we know our correct exposure time for each sub-exposure, let's look at some of the other camera settings we'll wanna set before going out. Okay, we're gonna look at some other camera settings here. Of course, this is a Canon camera, so the menu user might be a little bit different if you're using a different brand, but hopefully a lot of this will carry over. I'm gonna go ahead and turn it on. And the first thing that we can do is we can go ahead and set the exposure or shutter speed to what we figured out in the NPF formula. So for the 85 millimeter lens I'm using at F4 with this camera that and the Ryan Nebula right now, that's two seconds. I'm gonna use an ISO of 800. I would recommend using somewhere around 800 to 1600, especially if you have a Canon camera, this seems to be sort of the sweet spot for Canon cameras, but it's a good sort of starting place for any kind of DSLR really. Okay, next thing we're gonna go into the menus and starting with the first option here and the first menu image quality, we can go ahead and turn the JPEG option off and we want just regular full size raw image. So if your camera has raw capability, definitely just use raw, no reason to use JPEG. If your camera only shoots JPEGs, then use JPEG, but use the highest quality JPEG that it offers. But if it does have raw, use raw because you're gonna get better quality images that way. Okay, for image review, I'm gonna go ahead and turn that off. The reason being, and this is sort of important, we don't want to have the monitor actually active at all when we're shooting astrophotography. There's a number of problems that can happen when you have the monitor or LCD active, including IR leaks and just heating up the sensor in general. So go ahead and turn image review off. I'm also gonna turn the beep off. I like to just turn off any sounds that are going on. Mirror lockup is actually not a bad idea for this, but I'm not gonna talk about it just cause this is a beginner tutorial and I'd rather keep it more simple. I'm not gonna go through every option here. For white balance, I usually just put it on daylight. It really doesn't matter though if you're shooting raw, but if you're shooting JPEG, I'd recommend daylight white balance. Color space, again, probably doesn't matter, but I'm just gonna leave it on Adobe RGB. Picture style does not matter unless you are shooting JPEG only. If you're shooting JPEG only, I would recommend faithful or whichever picture style just says 0000. So it's not adding any sharpening or any effects to the JPEG. Okay, next up here we have long exposure noise reduction. That sounds good, but we're gonna do an actual manual calibration so we don't need it and we actually don't want it. So we're gonna go ahead and disable long exposure noise reduction. Same thing with high ISO speed noise reduction. Go ahead and disable that too. Basically, from this point on, I just sort of am going through and disabling things. We want as raw an output from our camera as possible. So usually that means disabling a lot of the neat tricks that your DSLR is supposed to be able to do. Let's see. We do know these matter. I'm going to enable exposure simulation. I believe what that's gonna do is make the picture a little bit brighter on the LCD, which is something we would want. Autofocus does not matter. I don't think really anything else in here matters. I'll just mention, you can always format your card in camera to have a fresh slate. So you have plenty of room on your SD card. That's another pitfall sometimes people run into is they don't have enough room on their SD card. So I'd recommend just backing everything up before you start and then formatting it in camera. Oh, and I should actually mention right above that, right here, we have auto rotate. I have heard that sometimes this can mess people up even with raw pictures. So I would recommend turning any kind of auto rotate off. I have my auto power off set to disabled. That's a personal preference. You might be more comfortable with it being set to eight minutes or something like that. Auto power off is only gonna happen when you're not taking pictures, but I just find it really annoying whenever the camera auto powers off. So I have it disabled on my camera. It's up to you. If your camera has LCD brightness, I would recommend turning that all the way up so that you can really see what you are working on. Cause everything that you're gonna be shooting is gonna be sort of dim. So having a high LCD brightness is helpful. But I'll just mention that you might also want to turn this down because if you are doing like photography with a telescope you might wanna know that you can actually turn this way down too and save your night vision a little bit. But for astrophotography, I'm gonna turn it up. While we're waiting for the sun to go down, let's talk about calibration frames. So I would highly recommend if you're following this tutorial to take calibration frames. They're gonna make your picture much better and easier to post process. What a calibration frame is, is it something that alters the raw picture in a way to either remove noise or to correct optical issues. And so there are three types we're gonna talk about. Bias frames, dark frames, and flat frames. Let's start with bias frames. I think they're the easiest to understand. With bias frames, it does not matter when you take them or what temperature the camera is at. All you just wanna do is just put it on manual exposure setting and just keep going all the way over until you're at your shortest exposure that the camera can do. On my camera, that is one eight thousandths of a second. So the shortest possible exposure. On other cameras, that might be one four thousandths of a second or something like that. And you wanna set your ISO to whatever you had it for your subs, often or also called your lights, your light frames. So for my camera, I set that to ISO 800. For yours, 800, 1600, 400, whatever it is, just make sure it's the same as what you were using when you took your pictures of the night sky. And then we're just going to set up our intervalometer to take, let's say, 50 bias frames. And we just let it go and it takes 50 of these very short exposures with the body cap on. And I would also wanna get away from these lights just in case there was any light leak because you wanna do this in complete darkness. You don't want any light hitting the sensor because what the bias frames are doing is they are just looking at the pattern noise that the sensor produces. So just the inherent noise of the electronics on the sensor, that's what we're trying to take in the bias frames and then we'll subtract that out in our processing with Deep Sky Stacker or PIX Insight or Astropixel processor or whatever that you use. The next up is dark frames. They're similar to bias frames and that we do them in the dark with just the body cap on or with the lens cap on the lens. But we want them to match the exposure time of our light frames. So we've determined using the NPF formula that we're gonna be taking two second exposures. I'm gonna be using ISO 800. And so I was just set that up on my camera. This should be the exact same settings that we use when we actually take pictures of the night sky called our light frames. And again, just take at least 30, I'd say. If you have the disk space, you can take 50, but 30 is probably enough. Just set it up on your inner volometer, set the N, the number to 30, and just let it go. Taking a bunch of two second exposures in the dark. That's darks. Oh, one last thing about darks. Unlike bias frames, it's important that your dark frames also match the temperature of your light frames as closely as possible. So what I would recommend is get out there early, let the sunset, when it's completely dark, and you've let your camera adjust to the outside temperature, take your dark frames. Then it's gonna get even darker. Because even when it looks dark to you, the night sky will get a little bit darker over the next half hour to an hour. And you now have your dark frames done. Then start focusing, lining up your camera with Orion and start taking your shots of the nebula or whatever deep sky object you are shooting. Okay, the last type of exposure, we need the actual lens. And we need it to be at the exact same focal point and aperture as when we shot the lights. So what I would recommend is if you can, bring something out into the field to take your flats. If not, just be very careful when bringing it into the house that you're not messing with the lens at all. What the flat frames do is they will take care of vignetting in the system, which is really common, especially with a lens-based system. And then also, if you have any little bits of dust or anything on your lens or your sensor, they'll also take care of that. And what we need for a flat is we just need a nice, as the name suggests, flat white surface to take a picture of. So there's a lot of different methods for doing this. You can try using Scott, the sky as a flat. I haven't had that much luck with that since the sky brightness fluctuates a lot. I've had people just take a picture of a white wall with some even lighting on it. What I usually do is I have an LED tracing pad, but you can also use an iPad or a computer screen and just put that flat up against the lens shade. So that you know that it's completely flat up against the lens shade and then just take pictures of that. The one drawback of doing it with an LED tracing panel is sometimes you get into the problem of you have such a short exposure that you get into the sampling rate of the power source. I don't know how to explain this better, but you see these lines in your flats. So if that happens, you just need to take a slightly longer flat frame or diffuse, but sometimes to take that longer flat frame, you're gonna have to diffuse what you're shooting a little bit. So just put pieces of paper between the LED tracing panel or the iPad and the front of the lens shade here and that should diffuse it enough that you can then take your flats. How do you know how long to expose a flat for though? This is where it's helpful to use the histogram on your camera if you know where that is. So basically just bring up the histogram feature. You should see a little bump that's all of the information in the picture, all of the pixel values and just bring that bump halfway over on your histogram on your camera and that's a properly exposed flat. It doesn't necessarily have to be all the way halfway over if it's between a quarter, a third or halfway over. As long as you don't have it like way over on the right side or way over on the left side, it'll probably work, but halfway over is a good rule of thumb for a properly exposed flat frame. And how many to take just like with your darks I would take somewhere over 30, 50 would be probably better, but it's not necessary. So at least about 30 flat frames. Once you know by trial and error where your flat frame is based on the histogram, the exposure value, then you can just program it with the intervalometer and then take 30 to 50 flat frames. Okay, hopefully that all made sense. So we again have the bias frames. Those are the ones that are as short as possible within the dark with either the lens cap on or the body cap on the camera. We have the darks which have to be matched in both temperature and time to our light frames, our subs, and then we have our flat frames. And this is where we need some kind of flat source of light and this can be like an iPad or an LED panel or a wall or whatever you have. We just wanna make sure that it's perfectly square with the camera. And the flat frames we're gonna expose so that the back of the camera histogram is about halfway over. And again, we'll take 30 to 50 of those. I'll just finish up this section by saying calibration frames are important. I know a lot of people are gonna wanna skip them because they sound difficult or tedious or whatever it is. They're really a good idea to do though and get in the habit of doing for all kinds of deep sky astrophotography. All right, it's now night and I'm all set up here. I've brought out a table. This is optional, of course, but I like to just have a table so that I can have some things already. So I have my intervalometer ready. There's my Bodnov mask. I have a little headlamp here. And then I'm gonna be doing some other things later in the night. So I have a bunch of other gear here. But what I'm also using this for right now is just as a way to sort of block some street lights and house lights over there from getting into my shot. So if we get down to the level of the camera, this thing is blocking those lights. But right above that is Orion. We'll just go through the different steps. We're gonna start with focusing, or no, we're gonna start with finding Orion. Then we're gonna focus on a bright star and then set up the intervalometer and then take our shots. And really that's it. The only other thing we have to do during the night is after a few hundred shots, we'll adjust and recenter Orion in the viewfinder. All right, let's go. All right, the first thing we're gonna do is we're going to find the Orion constellation. And like I said earlier, we're not gonna be using a finder because with a 85 millimeter lens, it should be easy enough to just find the Orion constellation with live view. I do have live view set to ISO 8,032 exposures just to trick the exposure simulation into giving me a nice bright view. This might not be necessary on all cameras, but on my 5D I've noticed it works. Okay, so now I'm just gonna loosen the tilt and the pan on the tripod here. I'm gonna start moving the camera around a little bit. And you can see I've already sort of lined it up with where I see Orion in the sky. So all I really have to do is just sort of tilt up here and there it is. Orion is one of the easiest constellations I think to find in your live view because that Orion belt is so bright that it's really easy to see. If we keep going up here, there's Betelgeuse, there's Orion's bow and arm and there's the belt. Even if I wanted to center the Orion nebula, it'd be right there in the sheath. But what I'm gonna center first is Rigel, which is this lower star at the bottom here and it's the brightest star in the constellation, which is why I wanna use it for focusing because with a lens, you really need a bright star to focus if you're using a Bodanov mass that we are going to here, especially a Bodanov mask, not really designed for this focal length. So we'll see how the well this works. Again, if it doesn't work, we'll go to my backup, which is the sharp star system. Okay, let me go ahead and zoom in. Just gonna press the zoom button, adjust where it's pointed, get Rigel centered there and then press the zoom button again to get it 10 times zoomed. And if you don't have any kind of Bodanov mask, you can still just focus with live view. The way to do it is just grab your focus ring, push in one direction, you'll see the star gets bigger. That's at infinity, infinity in quotes because it's not actually working. You can see then as I start twisting the focus ring, it gets smaller and then it starts getting bigger again. So you just want to find that place in the focus ring where the star is smallest. So I'm going to go down again and I think it's right about there. What you can do to test is now take a picture. I mean, I don't want ISO 8000 and 30 seconds because that would be completely blown out. So let me adjust these here. First, I'm going to adjust the ISO down to 800 and then I'll adjust the exposure down to, let's try two seconds. I think that's what we thought the right exposure time would be. Okay, I'm going to take an exposure. Okay, and then I'm going to go to playback and I'm going to zoom in as far as I can and just look at those stars. And what we're looking for is, do the little faint small stars look fairly pinpoint or do they look sort of blurry? And looking at Orion Nebula there, you can see we have some hot pixels and noise but we also have some stars here. I think there's a little bit of motion blur from my using the shutter button rather than a remote timer. So let's try that again. This time I'm going to set the camera on. Whoops, wrong button, a timer mode. Let's do a two second timer. Okay, let's zoom in again. That looks pretty good. Though, what I would really recommend if you have some time is to just adjust. Just try sort of try different focus points until you see that it looks the best. So I'm going to zoom in again. I'm going to try focusing it again and I'm going to take another exposure. Okay, I'm going to go back to playback mode, zoom in. And then I'm going to compare between this exposure and the last one. And I think you can see here that this one is much better. And so I know that I'm on the right track here when the stars are smaller and I'm seeing more faint stars in the picture. So for instance, here's the new exposure with the new focus point. Here's the last one. And I can see more faint stars and those stars are smaller points. So with trial and error, you can get good focus with out-of-bottom-off mask, but it's just much easier with one. So let's move on now to using one. And I'm going to start with my cheap one here. All right, it's in there. So now I'm going to zoom in and this might be a little bit harder to see. But we have this little line now that's coming out from the star core. And if I move the focus back and forth, you can see that line move as well. And what I'm going for is to try to get that line right in the middle. So I think that looks pretty good. It can help to have a magnifying glass if you have one, push that right up to the live view and you might be able to see a little bit more. But let's try this. Okay, I'm going to go back to playback mode, take. Oh, I'm going to go to playback mode. Sorry. And I left the bottom of mask in just to show you what we can see there. It still looks sort of just like a central spike. I'm not really seeing the X pattern. So I'm going to try a slightly longer exposure and see if we can get that X pattern to appear. Okay, still no X pattern. Oh, maybe I can actually see it slightly. Yeah, actually I can sort of see it there. Really faint, but it is there. And I can see that this is good focus. So now I'm going to take the bottom of mask off and take another exposure. I'm going to put it back down to two seconds. Okay, and this looks very good to me. So I think that the bottom of mask did help get a very good focus. I can see a lot of small stars. So now that we're focused, the next step is to set up the intervalometer. Okay, the first setting in the intervalometer is delay. So that's how long it would delay before taking the first shot. So I'm just going to set that to two seconds. The next setting is long. So that's how long each exposure should be. And we already found out using the NPF method that this should be two seconds. So each exposure will be two seconds. Set that. The next setting is interval. And so this is how long it should wait between each exposure. Since I'm just going to assume we're not going to use mirror lockup. It might be a good idea that I don't have it set up right now. I'm going to go ahead and do a two second interval between each shot. This will just give the camera some time to settle between each exposure. So we're doing a two second long exposure and then a two second interval. And then N stands for number. So the number of shots we want to take. And I'm going to set that to, this is sort of annoying. You just have to keep pressing it on this one. Okay, I'm going to set that to 200. Since we're doing untracked astrophotography, we're going to have to move the camera as Orion drifts out of the field due to the Earth's rotation. So 200 I think is a safe bet before we want to adjust the camera a little bit. The last setting on this intervalometer is do you want to make a sound when it takes shots? And I'm going to say, no, I don't want it to make any sounds. Okay, so now that we have everything set with the intervalometer, all we have to do is just have it hooked up to the camera and press the start button. Sometimes this will be a play button to start the process. All right, we'll let it do its thing and then look at what we get. All right, as you can see, after a couple hundred shots, Orion is no longer centered. So all we have to do is just re-center Orion like that and then run the intervalometer again. Before we do though, I would recommend how he's, whenever you start a new run, let's just refocus. So I'm just going to center Rigel back up there, put my Bodinov mask back on, zoom in on that guy and try focusing again here. I'm going to take a four second shot just so that I can see that a little bit easier. Okay, that looks pretty good. Okay, so you have to remember when you're focusing, take that Bodinov mask back off before you start your next sequence. But now we're ready to go. So I'm just going to hook the intervalometer back up and let it rip for another 200 exposures. One other thing I should note, I always remember to do before you start your intervalometer is turn off your live view because if that live view is on, sometimes it will stay on and that will heat up the sensor, giving you more hot pixels and it'll also drain the battery a lot faster. All right, we'll take another couple hundred and then we should be done for the night. Okay, after you've taken a few sets of 200 exposures, each time moving the camera over a little bit so you've centered Orion, you can call it a night. Personally, I'm going to stop now, but when you think about it, when you're just taking two second exposures, that doesn't make a very long integration, something like 15 minutes total. So if you want to keep going and you want to take thousands of exposures to combine together, that would be even better. You'll be able to get more out of it that way and be able to reduce the noise further. But in the interest of this just being a demonstration, I'm going to stop at a few hundred, but I encourage you to go as long as you feel like you have the sanity and dis-space and time to do. So next up, what we're going to do is we're going to take what we've shot tonight and look at it on the computer and then get into calibrating, registering, stacking and post-processing. So all the fun stuff. If you're following along with me, you can download these from Google Drive and just follow along with my example files here. Or if you're doing it on your own, I would recommend organizing your files into these four folders. So you have them all ready to go for the next step here, which is we're going to use DeepSkyStacker to calibrate the lights with the flats, darks and bias files. And then we're going to register those lights, which means match them based on the star patterns so that they're all lined up and then stack them into one complete image that has all of that data combined together and it rejects a lot of the noise both through calibration and just through the process of stacking the images together. We can reject a lot of things like hot pixels and just the inherent noise of the sky and the uncertainty of light. So we're ready to go here. Let's go ahead and open up DeepSkyStacker, which is this right here. I'm using the 64-bit version. It does tell me a newer version is available for download. I'm using 4.1.1 and this says 4.2.3 is available. I'm not going to upgrade right now, but I think it works the same way. We start over here on the left-hand side with, and we just basically step through these different steps. We start with open picture files and I'm going to navigate to that folder I was showing you before, Orion 85 millimeter. And I'm going to start by loading in my lights. I'm going to press Control-A to select them all and click Open. Okay, now those are all loaded. I'm going to go ahead and check all of those just to see how many we have here. We have 451 lights. I'm now going to go up here, back up to where it says registering and stacking and choose dark files. Go into my darks folder here. Again, click once and then press Control-A to select them all and then click Open. Okay, we loaded in 31 dark frames. I'm going to click on flat files. Load in my flats. Control-A to select all. Click Open. Load it in 20 flats. I don't have any dark flats this time. I'm going to use bias. So I click on bias files. Open up my bias folder. Press Control-A to select everything and click Open. And we loaded in 60 bias frames. Okay, so we now have everything we need here. Lights, darks, flats, and bias. The next thing I'm going to do is I'm going to click on this register checked pictures link right here. We can see here there's an actions tab and an advanced tab. It says dark flats and bias checked. That's good. I'm going to leave automatic detection of hot pixels checked. I'm going to go to the advanced tab and I'm going to compute the number of detected stars here. Okay, it found 200 stars with a 20% star detection threshold. That seems fine. If I wanted to, I could try raising that and then just try clicking that compute button again to see what happens. Okay, when I raise the star detection threshold, that number of stars goes down. If I lower that star detection threshold, like let's say to... I'll try 15%. We get a few more stars. This is probably fine. I'm going to leave that at 15%. I'm going to click into recommended settings and just see what we have here. It's saying that we're using sigma clipping combination method and sigma clipping median for the other calibration frames. That all seems fine. Basically, if this recommended settings thing found any problems, instead of showing in green, it might show things in red to fix certain things, but this all looks good. We can click on stacking parameters here and just see what it's doing. It's doing a median Kappa Sigma clipping. You can hover over these different stacking modes to find out what they do. This all looks fine. I'm going to click OK. I'm going to click OK again. It will start creating all of our master calibration frames. It starts with the bias, then goes on to creating the master flats and the master dark and everything else. Then it will go ahead and calibrate everything. And register those checked pictures together. Once we have all of that done, we can pick the best light frame to use for the final registration and stacking and then stack all of these pictures together. I'm going to let this go for a while here and check back in when it's done. It's now done. I'm going to go ahead and sort these by score and you can see the top score here is 1,862. That means that this has been when Deep Sky Stacker looked at all of the different lights. It found that this one had the roundest and tightest stars in terms of focus. I'm going to go ahead and choose that one as the reference frame. I'm going to right click on it and choose use as reference frame. We now get this little asterisk right there. I'm then going to go over here to stack checked pictures, which is the next thing down. And it looks like I didn't take my bias frames. It is the same ISO as my darks and flats and lights. That's not good, but oh well, it's too late now. It'll probably work out fine. You can see the total exposure here is about 15 minutes because we took 450 frames at two seconds each at ISO 1600. I don't want custom rectangle. What is that? I just want standard mode. I don't know what I did there. There's an option to stack based on a custom rectangle that I must have somehow messed up and put that in. So you always want to check all of these things, that it's what you actually want. I just want a standard mode where it's framed based on the reference light frame, which we just set. I'll use Kappa Sigma Clipping. That's fine. All these other things are fine. Let's click OK. I'm just going to click on recommended settings and just check through here. Looks good. One thing to keep in mind when doing a lot of DSLR frames like this, 450, is that it can temporarily use up a lot of space on your main hard drive. This is just because it uses a temp folder while it's doing this work. You can see that this is going to use 62 gigabytes of my 80 gigabytes free on the C drive. That's just something to keep in mind. You need a fairly large amount of free space in order to stack a lot of frames at once like we're doing here. But I seem to have it now, so let's go ahead and click OK and let it do its thing of stacking these all together. Okay, it's done stacking. It doesn't look like much here, but that's because it's not stretched really here. So we're just seeing the bright blown out parts, but we can see Orion's belt there and things like that. But we're going to do the stretching in other programs. So all we have to do now is make sure that it's saved the autosave.tif, which if I look in my lights folder here, scroll to the bottom. There it is, autosave.tif. That's all we need, actually. So we're going to use that in the next steps and move on to the actual post-processing programs, because this was just what we call pre-processing. So it's calibrating, registering, and stacking, and then we'll actually do the fun part right now. Okay, so we're finished with DeepSky Stacker. We're going to go ahead and move on to Photoshop here. I'm going to go to File, Open, and I'm going to open that autosave.tif file that we generated out of DeepSky Stacker. The first thing I'll point out here is if we go up to Image, Mode, we can see that this is a 32-bit image. Eventually, we're going to want to bring it down to 16 bits per channel, but for this initial stretch, we can leave it in 32 bits. But a number of features you can see are grayed out here, and part of the reason for that is because this is a 32-bit image, and not all features in Photoshop will work with a 32-bit image, but once we change it to 16 bit, then most of them will. So the first thing I'm going to do is I'm going to duplicate the background layer, and you can do that by either pressing Command-J on a Mac or Control-J on a window. Windows Machine. Or if you don't like keyboard shortcuts, you can right-click and choose Duplicate Layer too. I'm going to call this First Stretch. Okay, and then we're going to start stretching the image. Right now it's in what we call a linear state, meaning we haven't taken the curve and basically flattened it out into a nonlinear state. If we look at a histogram right now, just open up a histogram here. Oh, it's not working because we're in 32 bits. Okay, never mind. Let's go ahead and stretch this out. So I'm going to go to Image, Adjustments, Levels, or I can press Command-L. Okay, well here's our histogram. So we can see that this spike of information is all the way over here on the left-hand side, and what we're going to try to do is bring it over to the right while also spreading it out. So the way we're going to do this is going to take the middle slider and push it over a bit, press OK. And you can see we've already taken that spike of information here. This is all the pixels. So you can see we've already taken this spike. This is basically all the information in the image and moved it off from this left-hand side, which is the shadows. And we're going to do that again, getting a little bit further off the left-hand side. And don't worry that the image is looking really gray at this point. We're going to fix all that. I'm going to press Command-L again. This time I'm going to take this shadow slider, the one on the left, and I'm going to bring that over a little bit. This is resetting the black point. Now we don't want to do it just by look because if we do that we're going to start clipping information and we don't want to clip, meaning permanently bring any pixels down to a zero level yet. So I'm just going to bring it over here right on the left of the histogram, but not actually going into it. And then I'm also going to take the middle slider and bring it over again. We're going to do that a few more times. You can see this time, in addition to moving the histogram bump over, it's also spreading it out, which is what we want. We want to spread this out right in this area between the shadow and the mid-tone slider. So I'm going to take this over again. Take this over again. That time I just reset the black level, but this time I'll take this over and I'm just going to reset this one more time. Okay, so it still looks a bit weird, but that's okay. This is just our first stretch, as I said. If I zoom in now, though, what's cool is we can already see there's a lot of cool detail here. There's the Orion Nebula and you can see the outer lower rim of it there. There's the Running Man Nebula. You can just make out the horse head and flame there, too. So things are not looking too bad. The next thing I want to do, though, is I'm going to go ahead and turn this into a 16-bit image. So I'm going to go to Image, Mode, and switch it to 16 bits per channel. And I'm going to say Don't Merge. Okay, now I'm going to duplicate this first stretch layer just by pressing Command-J. I'm going to rename it and call it Background Prep. Okay, I'm going to select all by pressing Command-A or Control-A on Windows. I'm going to press Command-C to copy that layer. And then I'm going to press Command-N, or I can go to File-New. And it will copy over the size of the layer from the clipboard. So I don't have to change anything there. I want to make sure that I'm working in 16 bits. And I'm going to call this BG for Background. Then I'm going to go ahead and paste in my clipboard just by pressing Command-V or Control-V on Windows. And I'm going to go ahead and start working on this. First, let me just go ahead and delete this background layer. Okay, I'm going to start basically using the Dust and Scratches filter to get rid of everything but this gradient in the background, which we're then going to subtract from over here so that we don't get this distracting light pollution in the shot. Okay, so let's go ahead and go to Filter, Noise, Dust and Scratches. Filter, Noise, Dust and Scratches. And I'm going to use a slightly bigger radius, maybe something like 60. And using a 60 pixel radius on Dust and Scratches means any feature that's smaller than 60 pixels will basically just be filtered out. So we still have these big star halos, Rigel and the belt stars, and we still have Orion there. So to take those out, I'm just going to use a Spot Healing Brush. So if you go over here or you press J on your keyboard, you should get the Spot Healing Brush. And then I'm just going to click over those little spots that are left to get rid of those. And maybe I'll just follow up with a little bit of Clone Stamp here. The way the Clone Stamp works is you just press Alt or Option, set a sample. So I'm going to set this sample to the left here and then I'm just going to, and I don't like that actually. Maybe I'll just use this Spot Healing Brush a little bit more but turn down the hardness a little bit. Okay, I think that improved it a little bit. Basically, we're just going for as smooth a gradient in here as we can get without any hot spots. We do have some weird stuff going on in the corners here, but I suspect we're going to crop those out anyways. This is looking pretty good. So I'm going to go ahead and just save it. Let's save it to my desktop as the background. And after that saves, I'm going to go ahead and save my main document too. Basically, whenever we've put in, you know, more than 15 or 20 minutes of work, it's a good idea to save. So I'll just save this as Orion. I want to save it as a Photoshop document. Okay, we still have our selection outlined there. So I'm just going to go to Select, Deselect, or you can press Command-D, Control-D on Windows to deselect. Okay, so now we've deselected this. I'm going to rename this layer from Background Prep to Background Removed because we're about to remove the background from this layer. And what I mean by that is we're going to take this, which is the gradient of the light pollution and the really bright sky, and we're going to remove it from this, revealing a lot more detail. We're going to use a little-known thing in Photoshop called Apply Image. So if we go to the Image menu up here at the top and choose Apply Image, by default, it applies the image we're working on to itself and it multiplies it. What we want to do is we want to use that background image so I'm going to choose, under Source, I'm going to choose BG.PSD. And I think it just has one layer so it's probably fine to use Merged, but if you're seeing something weird here, you can just choose Layer 1, but it just has one layer because we deleted the bottom layer so that's fine. For Channel, we want to use RGB. For the Blending Mode, we don't want Multiply. We want to go down to Subtract because what we're trying to do is subtract the background gradient from the image, but leave everything else. And by default, it's subtracting very aggressively and the reason for that is because the offset is zero but we want to put in a bit of an offset and this may vary depending on your image. So I would just recommend starting with 10 and then basically increasing the offset by 10 until you get to a point where basically you have a fairly gray image like this. It can help to zoom in because you can see, you might have thought, oh, well, the image looked better when he was at an offset of 10, but we're then clipping out a lot of the detail so what we want to do is we want to keep bringing that number up, that offset until we're not clipping into any of the actual shadow detail and so you might need to bring that offset up to 40 or 50 or 60 before you can be sure of that because we can always bring the black level back down but we don't want to clip any data at this point. So just make sure that you're not clipping anything. I think that looks good. So if you want to just sort of look at how my image looks here and try to get yours looking somewhat the same as mine, this is sort of how we want it to look. We've really removed that gradient but we're not yet done processing so don't worry about it looking perfect yet. I'm going to go ahead and click OK. So now to compare what we just did versus where it was when we first stretched it, I can just turn off and on this layer called background removed and you can see that was before and that's after. So we've really flattened out the background gradient and it looks a lot better already but it's not a very dynamic picture yet because we haven't messed around with curves or saturation or anything like that. So the next step is I'm going to duplicate the layer again. Pressing command J and I'm going to call this second stretch and the nice thing about duplicating layers like this is if you ever get into a bind and you really don't like the work that you've been doing for the last so many minutes you can always just delete that layer and try again. So I always just after I complete a step in Photoshop so we went from the unstretched background image. This was when it was still in 32 bits. Then we stretched it. We turned it to 16 bits. We used the apply image trick to remove the background and now the next thing we're going to do is we're going to stretch this layer second stretch. So let's go ahead and click on that and press command L to bring up the levels again and I'm going to go ahead and bring this over a little bit and bring the black level in a little bit and you might need to zoom in to really see what you're doing but basically I'm just trying to add contrast to the image by stretching it out and I'm especially looking at the horse head there and the Orion nebula and we're starting to see the witch head here too. So as you stretch an image you'll notice that new things appear but possibly also new issues like we reveal a lot more noise in the background but that's okay. We're going to use M78. That's a cool little nebula right there. Okay. Next thing I'm going to do is I'm going to do a curves adjustment. So I'm going to do image adjustment curves or command M and I'm going to apply pretty aggressive what's called an S curve here where you take down in the shadows and bring up in the mid tones and this is basically the same thing we were doing with levels it's just a different way of doing it. Okay. At this point what I want to do is it's looking pretty cool but I want to bring out the saturation a little bit so I'm going to go to image so I'm going to go ahead and say that's good for the second stretch so let's duplicate that again call this our saturation layer let's go ahead and save the image let's go ahead and raise up the saturation a bit on this saturation layer I'm going to go back to my image menu adjustments I'm going to choose hue slash saturation and sometimes you know this is when you really want to zoom in and out a bit to see what this is doing because sometimes it's hard to see and it also looks at different parts of the image like you might bring the saturation up like that and think that looks really good on Orion but then when you look up here it just brings out so much ugly color noise and then when you look back you're like oh the color noise is right there too so be careful here I'm going to maybe do 30 plus 30 to the saturation it's still added a nice boost to Orion there let's turn the preview off and on you can see it did boost the saturation of it we can also, if we wanted to get fancy do some targeted saturation boosts so we could mask the nebula and just saturate that part I'll go ahead and show you how to do that so I just canceled that so let's say we just wanted to really give Orion here a big saturation boost but none of the rest of the image or let's say we just really wanted to give the horse head and the flame a saturation boost what we can do is we can add a hue slash saturation adjustment layer not the image menu option because that applies it directly to the layer well this is going to just apply it as an adjustment layer that applies to everything below and I'm going to go ahead and bring that saturation way up like we did before bring it up to like 50 but then on the hue slash adjustment layer you can notice it has this mask it's called the layer mask and we want to just go ahead and fill this with black you can do that black is your foreground color you can just press option or alt-delete and that's going to fill that layer mask with black another way to do it is just edit fill and we can fill with black that way so you can see since we just filled that hue slash saturation layer with black it took it off so now we're back to where we were but what we can do is we can now paint where we want it to apply so I'm going to choose the paint brush here I'm going to make it about 80 or 50 or 80 pixels something like that, that looks good I'm going to make it a nice soft brush so I'm going to use 0% hardness and I'm going to turn down the opacity too so I'm going to turn the opacity down to 70% and then I'm just going to paint in where I want this to apply and I have to make sure that I'm painting with white so if black is your foreground color right now just press X and that will switch them or you can use this little double arrow down here to switch the foreground and background color I want to make sure I'm painting with white and then I'm just going to come in here and I'm going to increase the saturation of my nebulae with the paint brush and some people will hate that I'm showing you this because they don't believe in this kind of painting on your image but as a quick hacky thing I think it's fine if you're doing this for yourself and you just want it to look how you want it to look then who cares how you do it if you're really concerned about the ethics of imaging if you think that this is a bad thing to do then don't do it anyways what I just did was I increased the saturation of Orion and the horse head and the flame without increasing the saturation anywhere else maybe I'd also want to do it on these bright stars I think that looks sort of cool do it on Rigel here yeah so this is looking pretty nice still have a little work to do with making it look really good though let me go ahead and add another curves layer I'm just going to reset my black point here a little bit something like that okay so last thing here if we're doing a quick process or no there's two more things one is if we look at our corners these are really bad also the edges have this weird color modeling we want to crop this down a bit I'm just going to grab my crop tool here put it on unconstrained and I'm just going to go in from the corners a little bit keep Orion roughly centered do something like that and I'll just examine it make sure that now all the corners look good still a bit of weirdness up there so maybe I'll crop this in a bit more to keep Orion roughly centered I'll edge this one in a bit too one thing I'm looking at over here that I don't want to crop out is we have the witch head nebula really fainting right there so I don't want to crop that out okay that looks pretty good though okay in a quick process probably the last thing I would do here is these bright stars all have this sort of magenta into violet ring around them and I just find it pretty annoying especially when you're looking at it about that scale or something it becomes pretty noticeable and sort of distracts if you don't find it objectionable then you might be done with this this looks pretty good but if you want to work on those violet halos a little bit I'll show you a technique we can use first when I do these kind of local adjustment things you want to work on a fresh new layer but now that we've added these adjustment layers we can't just duplicate the last layer we were working on so instead what we have to do is we have to press command option shift E or that would be control option shift E on the windows and what that does is it takes everything that is visible here and it creates a new layer based on that so this layer will look exactly like what we had visible before but it's a fresh new layer we can start working on I hope that makes sense I'm just going to call this removing violet halos and so the way we're going to do this is we're going to select the violet halos and then change their color and desaturate them a little bit so to select them I'm going to use select by color range which is under the select menu and I'll start by just clicking once on the violet halos and you can see it already did a little bit here fuzziness starting at 40 that's fine then I'm going to switch to the add to sample mode if you want to do this on the fly you can just hold down shift while sampling and that will also switch it to that temporarily but I'm just going to since I want to make sure that I'm using I'm just going to go ahead and choose it there and I'm just going to select a bunch of these halo colors want to be fairly zoomed in and careful while you're doing this not to add anything that's not what you want okay and then to see how well it selected what I can do is I can turn the selection preview from none to grayscale okay and you can see that it did select some of our nebula there that's okay we can fix that in a second but on these some of these lower stars here you can see it didn't quite complete the halo so I'm going to go ahead and switch this back to none and grab a little bit more ooh okay I think I went overboard I'm going to go ahead and undo hmm okay I think I messed that up well we'll just start over so to start over just go back to your regular eyedropper here and we'll start again this is a pretty common thing with the color range tool so you can go overboard pretty quickly and you might have to start over we might not be able to get all of these really faint ones that's okay though the ones that are more distracting are the bright violet halos okay let's see how that looks I'm going to play around with the fuzziness slider a little bit here zoom out a bit and when we do play around with the fuzziness slider you can see that sometimes it's really picking up on color noise in the image and sometimes it's not I'm okay actually with it picking up on a bit of color noise because that actually might improve the image to reduce that a bit but for now let's just focus on the halos because instead of just completely desaturating them like we could with the color noise I also want to try to just turn them a little bit blueish instead of the violet so let's try that I'm going to turn down the fuzziness quite a bit turn it down to 11 okay and now you can see, especially if we zoom in that it has all these little halos selected but it also has some stuff in the Orion Nebula here that we don't want to turn so I'm going to press Q which brings up this sort of ruby overlay and you can paint on this with the brush tool I want to paint with 100% opacity and I'm just going to paint in black where it's picked up something that's not a star halo which is picking up a lot of the Orion Nebula in here which I don't want it to do so I'm going to go ahead and paint that all in it with black let's see how it's done the running man yeah same thing with the running man we don't want it to eat away into the running man okay good enough zoom back out here press Q again that just altered the selection now we're going to go ahead and click on hue slash saturation an adjustment layer sorry hue slash saturation adjustment layer and what it did if I press option or alt and click on this layer mask is it just took our selection and it added that automatically to the layer mask for this hue slash saturation layer and now what we can do is we have a lot of flexibility we can open up I'm going to zoom in and we can open up the properties for this hue slash saturation layer and we can play around with this to try to fix these stars a bit so you can see if I do that it gives it a very artificial look but we could change the star halo colors the mask isn't quite good enough I might want to blur it if I wanted to do that too much but what I'm going to do is I'm mostly just going to de-saturate and turn down the lightness of these bright halos and what that does if I turn this off and on is it basically just shrinks the stars and really de-emphasizes those halos so if I zoom to sort of a normal level here and I turn that off and on it's sort of hard to see at that level try there sort of subtle but I think you can see it it's basically you have these really bright halos and then we can de-emphasize them a bit with this trick and your violet halos might be worse than mine it's really all up to how the lens is designed okay I know I said that was the last thing but this green cast is still bothering me a little bit so the last thing I'm going to do is I'm going to open up a selective color adjustment layer here and I'm going to go to the blacks and I'm just going to take out a bit of cyan take out a bit of yellow and a little bit less of the magenta and increase the black level just a bit oh yeah I think that improved it a lot you can see here's before hope you can see this in the video there's a green cast sort of across the background sky and then just playing around with selective color blacks taking the cyan and yellow down to negative 5 the magenta down to negative 3 and the black to plus 6 I think that's a big improvement on the sky color okay so the focus on this picture I think is clearly Orion Nebula and the running man we captured that pretty well we also have the nice bright star Rigel here we have a little bit of the witch head you can see her nose and mouth a little bit and chin zooming around here we have the nice belt stars and we have the horse head and flame so we've captured a bunch of nice nebulas I hope that you have learned something in this tutorial last thing I'm going to do here is just save this for the web so I go to file save for web and newer versions of Photoshop I believe they've moved this to the export command maybe just look around for it it might say save for web legacy but it's a really nice way to save off your extra images because it just has a lot of options and a nice big box I just really prefer this and you can change things very quickly it always has that convert to sRGB option it has a nice estimate of how big the image will be let's you scroll around and see when you change for instance the quality what it's going to do to the image if it's going to soften it too much but I'm just going to save off a 100 quality JPEG and another thing you can do down here is you can change the size so let's say I didn't like how this looked at 100% so I'm going to change the size to 3,000 pixels wide see how that looks now maybe I like the look of that better it gives you these different options for how it's going to resize it for Astra images I would always recommend by linear I wouldn't use bicubic or nearest neighbor definitely not nearest neighbor but I think of these options by linear is your best bet as the resampling method when you're shrinking an image I should point out I would never recommend really blowing up an image making it bigger and enlarging it so if you're shrinking an image used by linear okay this looks good let's just fit it in view just to make sure I still like how that looks yep that looks cool so let's go ahead and save it Orion.JPEG I'll save it to the desktop here and take a look in preview make that full screen yeah I think that looks really nice it gives you a sense of most of the constellation maybe I could have framed it better vertically and gotten beetle juice in there oh well, next time so I'm happy with this I hope that you've learned something about taking short exposures and showing that you can bring out a number of Nebulae in even wide field exposures with the right techniques I hope that you subscribe to my channel and if you have want to keep seeing videos like this one you can also support me on Patreon well, till next time, clear skies this is Nico Carver from NebulaFotos.com