 Okay, today I'm gonna be using Cyril on my Mac to do the stacking and some of the pre-processing tasks and then probably finish off with GIMP. This is the second part of my Lagoon No Tracker series, so if you haven't watched the first part where I show how I captured and planned for this shot, I recommend watching that first. The link will be in the description. And Cyril is a free open source program that's really cool for, as it says here, astronomical image processing. The website is s-i-r-i-l dot org. And today I'm... I think last time I showed Cyril, I went to the download tab here and just used the latest release. That wasn't a beta release, but the full release that they do. Today though, I just I'm really interested in their beta release that they talked about here in the news tab. It's also available here on the download tab under beta testing. And the reason I'm so interested in this one is it's basically an early release of their 1.0 version where they've updated the user interface and done a bunch of other cool things, including 32-bit and all kinds of things. So I am gonna try this. We'll see if we run into any bugs since it is a beta. If you're not comfortable with it with running beta software, then you can always watch my earlier Cyril video to see the .9 release. Okay, anyways, I've gone to the news tab here, clicked on this 1.0 beta testing article. And then if you scroll down to the bottom of the article, there are prepackage downloads for Windows, Mac OS, and Debian. So I'm gonna click on Mac OS because that's what I'm running here. And then just go ahead and open the DMG file. It's a package file for installing Mac software. And just drag this to my applications folder and replace the existing version. Okay, I can eject this temporary drive now, close out of Chrome. And I'm just gonna go here to my finder and click on go to applications and double click on Cyril. And if you get this when you first install Cyril that it can't be open because it's from an unidentified developer, this is a new Mac security setting. One way to get around it is you can just right-click on the application and click open from the right-click menu. And then instead of just saying cancel, you now have this open button right here. And that will let you open that application. Once you do that once, it will remember that setting and will open it every time like that without giving you the security warning. Okay, there's a little thing here saying that if you, that they're gonna show us an introduction. That's pretty cool. I'll say okay. Okay, we've gone through the little tutorial. I'm gonna go ahead and make Cyril full screen here. And the first thing that I'm gonna do is change my working directory, which you do by just clicking this little home icon right up here. And I'm gonna change my working directory to the desktop and then this Lagoon folder that I created. And if you're new to Cyril, let me show you this folder. This has my biases, my darks, my flats, and my lights, just like I showed you in the part one of this video how I sorted those. We did all that by looking at what was on the camera and then sorting the raw files. So we are all ready to use a script inside Cyril because we have a working directory. And then inside that working directory, we have these four working directories that have to be named just like this biases, darks, flats, and lights. Okay, I'll open back up Cyril here. And I'm going to go to scripts. And I'm going to do one shot color pre processing. Alright, and it starts. You can read about what it's doing over here in the console. Basically, it's gonna first create our master bias, master flats, master dark, then it's going to calibrate the light frames and register them and stack them together. So you can of course do all of this manually right here just by following along with pre processing, meaning calibration, registration, stacking, so forth. But we're going to do it the easy way today. Just to make this video a little shorter and use the script OSC for one shot color pre processing. Okay, I'll let it do its thing here and it'll probably take quite a while because we're dealing with hundreds of frames. And then when it's all done, we'll see what it produces. Okay, it's done with pre processing. So now I'm just going to open up the result, which is right here in my lagoon folder result dot fit. And when I open it, it's not going to look like much. That's because I'm in the linear view mode. So if you've used other programs that do stacking a lot of times when it's done, it'll just look sort of black like this with maybe a few little white dots that are star cores. But this is completely normal result. What we want to do is turn on the image preview that will give us a stretched view, but only as a preview, it's not actually going to apply the stretch yet. And so we can do some work like background extraction and color calibration, when the image is still in this linear state, and then those processes will work better. So to turn on that preview, if you look down here at the bottom of the window, there's this little display mode option. And it says linear. And I'm just going to change that to auto stretch. Okay, and I guess I had the red channel selected up here. So this is the red channel. There's the green channel. There's the blue channel. So you can see, for some reason, the green channel came out quite a bit brighter than the red and the blue. So if we look at the RGB image, it's very green. But that's fine because we're going to do the first thing we're going to do is a photometric color calibration, which is going to correct that color balance issue. And so to bring up that process, we go to the image processing menu up here at the top and go down to color calibration and then photometric color calibration. And what we want to do in here is just type in the relevant details right here. So well, actually, so starting at the top, you're first going to search for an object that is in the picture. So that's as close to center as possible. So I'm going to do m20, which is the Trifid nebula, because that's in the picture. And it's a little bit closer to center than the lagoon, which is m eight. And click find. Then you just can click on it and it will put in the the RA and deck of that object, telling you that's where this picture is pointed. That's good. And then we're going to put in the focal distance, which was 50 millimeters, and the pixel size in microns. So if you are if you don't know what your pixel size is, what you can do is just type in the name of your camera. So I was using Canon 60d and pixel size. And if it doesn't pop up right here, like in this case, it did 4.3 microns. If you don't see it there, like as a featured snippet from Wikipedia, if you usually can find it in this website, digicam database. And so pixel pitch is the same thing as pixel size. So it's saying 4.2 microns are rounded up 4.3, either is going to work. So I'll just type that in here, I'll use the more accurate one of 4.29. Okay, and then that tells me that I have a resolution of 17.6 pixels per arc second, which is very, very what we call under sampled, meaning if we really zoomed in on our stars, they would look sort of blocky, but that's okay, because this is a wide field image. Okay, and then I'm just going to leave everything else automatic and click Okay. Okay, that failed because it said it couldn't plate solve. So I have this hunch that the reason is is because of this black border over here. So I'm going to try this again. But first, I'm going to crop the image. And the way to crop in serial is you just draw out a box of where you want to crop. So I'm going to try to get as much of this in here as possible. But cropping out this black part of the edge. And then you just right click and choose crop. Okay, then I'm going to try running that photometric color calibration again, and just see if this works any better. Okay, and my hunch was correct. It was able to plate solve that time after I did the crop. And it did seem to apply the correction. So I'm going to go ahead and close this and go back to my RGB. And you can see now it's much better color balance. Okay, so next up, what we want to do is do a little bit of background gradient removal. We'll at least try it. I'm not sure if it's going to work on an image that has so much is filled with the Milky Way so much. But I'm just interested to see if it can improve the image a little bit. So let's go up to image processing and go down to background extraction. And I don't want to click generate because that automatically applies the samples and it's not very intelligent about placing images places them in a grid basically. And since there's so much Milky Way and Nebulae and stuff in this image. I want to place them myself and I'm going to place them more strategically. So I'm going to do it just by left clicking over here in the image I'm going to do. Oops, it says you can't place them on the RGB. So I'm gonna have to place them here on the red. That's fine. So I'm going to place them sort of on the dark Nebulae, rather than in this place that's really in the places which are really bright. If you can in your image, you want to actually place it on the background sky. But I've found that at least with pics insight that placing samples on the dark Nebulae can work to at least for an image like this one. So and we just want to try to get as much coverage as possible, you don't have to place that many samples usually something like eight to 10 is enough. This this corner might be an issue because there's not really anything super dark down here, but I'm just going to place it there. I'll place one down here. Okay, so again, this is an experiment, we'll see how it works. If it looks really wonky, then we can undo it. Go ahead and apply. Okay, it's telling me not enough samples. So okay, I'll do some more. And again, when I'm when I'm placing these samples, I'm just trying to at this point, just basically trying to pick darker parts of the image and avoid big stars. Okay, we'll try that. Okay, it did it. I'm going to go ahead and click close. And here's before and here's after. And it's a mixed bag. You know, I don't think it I think it hurt more than it helped. Because it's just it's just changed the the color balance and but there's it created different problems, but didn't really work how I wanted it to. So if someone has better suggestions for for how to do that, please let me know in the comments, but I'm gonna I'm gonna not apply that background extraction with this milky way shot because it's just it's not working. And that's pretty common. Even in pics inside I would have trouble probably extracting a clean background out of a shot that's this filled with milky way. And honestly, there wasn't too much light pollution. So I don't know if it really even needs that. I'll probably just crop some of this side and this side a little bit anyways. Okay, let's keep moving here. There's not much else to do in zero before we move on to the new image manipulation program for some final touch ups. There's probably actually a lot more you could do in here but I just still am learning the program. So sometimes what I like to apply a little bit of color saturation in this linear state. And so I'm just gonna apply something like 0.2. Let's see if that made any difference at the preview. Maybe we'll do a little more. Let's try 0.4. Okay, yeah, I think that looks better. So applying a little bit of saturation to the linear image, I think sometimes helps later on in the processing. So I'm going to apply that. Okay, and if we go back to linear, you can see this picture is still in its linear state, we just have this auto stretch turned on, which is why we're seeing it like this. Okay, before I save this to move into GIMP, let's change it to 16 bits. Converting, it says may lose some precision. That's okay. Just click okay there. There we go. Save the image in a different name. So right next to the save command is that and I want to save it as a TIFF file. There we go. So just pick TIFF from this list and click save. Oh, and I guess we didn't have to switch from 32 to 16 up there, we could have just done it right here in the saving command. So you can ignore that earlier when I changed from 32 to 16 there, you can always just do it, I guess, when you save the TIFF. So this is what we want 16 bit integer, click save. Okay, and now we're done with serial, we're going to move on to GIMP. Okay, I'm using GIMP 2.10. That's what I recommend. I think it's the latest major release. You can always just download it straight from their website. And we're going to do file open and pick this serial result.tif. It says it contains orientation metadata. I'm saying I'm going to say keep original. I'm not sure what that's about. Okay, so here is GIMP. The first thing I'm going to do is I want to fit the whole image into the window here. So I'm going to go to view, zoom and do fit image and window. Okay, and then the next thing I want you to do is if you see brushes over here, see if you have a tab for histogram, if you do go ahead and switch to that. And make sure that your histogram is in RGB mode. If you don't see the histogram, just go to dockable dialogues and pick it from this list right here and it should come up. I'm just going to go up here to the colors menu and go down to levels. Grab my mid tone sliders this little triangle right here in the middle and drag it over to the left to start stretching the image and click okay. And you should see this this histogram peak come out here. And what we want to start doing, we're just going to keep going back to that colors levels command is stretch the image. So basically, we're taking something where the dynamic range is very compressed, all the information is compressed into this little peak right here. And we want to stretch it out make it wider. And we're going to do that by taking the shadow slider and moving it to the right and taking the mid tone slider and moving it to the left. And each time we do that, it should it should make the the width of this histogram information wider, meaning that we're having we're getting more shadows mid tones and highlights bit by stretching it out and adding contrast. So I'm just going to do that a few more times. And when you take this shadow slider, you can move it pretty far over here to the right, you never want to pass the peak though. So I always bring it to just up to the left side of the peak of the information but never passed. Alright, that's a good enough stretch for now. Next thing I'm going to do is the image somehow I guess that was what that message was about is that it somehow got rotated 180 degrees. So let's go ahead and rotate it back to how we had it before. So I think that's just under view, flip and rotate, and we're just going to rotate 180. Okay, there we go. And then there's still a little bit of issues on the edges here of the image this this corner this corner this corner, I'll have little black edges. And there's a little bit of a color shift from green to magenta across the image this way. So I'm just going to crop away a little bit of the image here. Just with the crop tool. And I'm just going to start up here in this corner. And bring it down like this. And just crop away. And you can take these corners and adjust it. And I'm just trying to adjust it so that I have the omega, the eagle, the triphid and lagoon all still in the image. And that I can just get as much of the images I can without getting sort of the weird stuff in the corners. Okay, that looks good. I'm going to go ahead and press Enter to accept that crop. Okay. Next, what I'm going to do is I'm going to add some saturation to the image. I'm going to go back to the colors menu and go down to saturation. And just take this scale slider here and move it over to the right. I'm going to move it to about 1.5. Okay, I'm just going to zoom in on the image now a little bit. Just doing a shift equals or plus my keyboard to zoom in. Just check out a few of the details here. Oh, this is weird. It got also got flipped horizontal. This is the triphid should be on this side of the lagoon. Okay, so let's let's fix that. That's under view, flip and rotate. Let's flip horizontal horizontally, I think. Yes. Okay, sorry, I don't know what all these flips and rotations are about. But now it's now it's right. So this is looking really nice. I can see a lot of detail in here. I think we can add even a bit more saturation though. So I'm going to go back to colors, saturation, and add some more. Yeah, that looks good. So I added another 1.3 to the scale. And I think this is the is the right amount of saturation now. Okay, I'm really impressed by this I think it actually is looking better than our results in deep sky stacker and gimp or deep sky stacker and Photoshop. It's a little bit more subtle, but also not as noisy and I think more polished looking. Okay, next, we're going to remove the stars from the image and then add them back in. And so this is where for this, we're going to use a another piece of software. So we've started in serial, we've moved into gimp, we're now going to bring it out of gimp, use another piece of free software called star net plus plus, and then we'll finish back in gimp. So to use star net plus plus, we want to save this as a tip file again. And so I'm going to do file, export as, and I'm just going to save to the desktop and call it lagoon for star net dot tiff. Okay, so from Google, I'm just going to search for star net plus plus like that. And the first search result here is this source forge net download site. And that's what you want to go to. And then go over here to files. And if you do have PIX insight, you can get the PIX insight module. But assuming you don't have PIX insight, we're going to just get the standalone version. And so you would just go into version 1.1 here and then pick your operating system. So if you're on Windows, pick Windows or Win. If you're on Mac, pick this Mac OS and if you're on Linux, pick the Linux one. And I'll just click on that. And then it will start downloading here. Okay, it's finished downloading. So I'm just going to open up those open up the zip folder and put it on my desktop. And if you look at the read me, this is where it's going to give us instructions on how to use it. Okay, and basically, we just have to look at this little shell file here. This is just a little command that's given. And if we open that up, I'm just going to open it with a text editor, but you can open it with any kind of text editor, it doesn't matter. All we're going to do is just change this right here to the name of our file. So I'm going to choose, I'm going to say, Lagoon for star net tiff. And then I want the output to just be Lagoon starless. And then the last thing here is I'm just going to change the stride number to 32. What that means is that it will take a little bit longer to process than with a stride of 64, but it will give us a better result for removing the stars, especially with wide field images like this one. I'm going to go ahead and save that script. Close out of that. Okay, with that done, we've edited the script. 32 bits stride has the right file name. We can go ahead and run the script. The way we do that is through a command line program. So I'm just going to use the built in command line program on Mac, which is terminal. And to run it, we have to do two things. We first have to move to this directory. So I'm just going to type in CD space to do change directory command and then drag this folder over. So CD space, and then go to the folder, hit Enter, we're now inside the folder. And from there, I can run this command just by dragging it over and hit Enter again. Okay, and then it starts its thing. It reads the file. It tells me, yep, it's a 16 bit file with three channels. Here's the height and the width. Here's the CPU I'm using with TensorFlow. And then this is the number of tiles that it's going to break the file up into and then it's going to look at each one and remove stars from those tiles and then recombine the image. And then down here, it tells me how long it's going to take for that to happen, a percentage as it's going. And you can see it just went from zero to 1%. So it does take quite a while, probably at least an hour, maybe two, on an image of this size. Okay, back in Gimp here, I'm going to do file open and open our new starless image. And we're just going to apply a few tweaks to it, make it pop a little bit more. So I'm going to go to colors curves, which curves is basically just like a more advanced version of levels where you have your whole range of shadows to highlights based on this line right here, and you can place points wherever you want, and bring things up and down. And so what I'm going to do is I'm going to bring up the mids, and bring down the shadows with this curves like this. This is called creating an S curve, because it makes sort of like an S. Okay, and right now I'm in the value mode, I noticed that in the shadows, there's a little bit too much green. So I'm just going to bring down the green just a tad, like that just by eye, it's a pretty subtle adjustment. And I think there's a little bit too much blue to so I'm just going to bring that down just a tad. That's good. I'm just going to go back to value and now just bring up the whole image just a little bit perfect. Okay, I click Okay. And then I'm going to go back here and increase the saturation just a bit. Let's just do 1.15. Okay. And now that this image is boosted, let's add back in our stars, we can do that by just doing edit, copy visible, and edit paste. Why did it come in flipped and flipped again? I'm gonna have to figure that one out is something that I did when I opened this image for the in the first place out of Cyril, it was like flipped and then I guess I chose the wrong thing. Sorry about that. Anyways, we can rotate this layer. Okay, we want the tools transform tools. And I want to flip that layer. There we go. And I want to rotate it 180 degrees. Alright, so now we're back on where we should be. I can just call this pasted layer stars. And to this stars layer, what we want to do is change the mode from normal to screen. So right up here in the layers panel, you'll see the word mode and then it says normal, just click on that word normal and change it to screen. And the first thing you'll see is the image will get a lot brighter, but you'll see a lot more detail in the image. And that's perfectly normal. Basically, what it's doing is it's it's it's applying a sort of multiplication of the two images but but making the dark parts of this top layer transparent so that you're seeing into the image below. And what we have to do now is reset our values, our black point and our white point on this image. And we can do that with curves. But to do that, we first want to just basically create a copy of what we see here. So to do that, we're going to go to layer new from visible. So now we have this new visible layer on top. And on that visible layer, I'm going to do colors curves. And I'm going to reset the black point just by dragging this shadow slider over. And then I'm just going to bring down the shadows just a little bit and bring up. No, actually, I think just the whole image should just get a little bit darker. Looks better. We still have this sort of green cast in the middle of the image here. So let me just see here if I can fix that with a green curves. You know, that looks pretty good. That definitely helped a lot. It maybe is making the top part of the image a little bit too blue by removing the green from the middle. If I really go for it, you can really see the top part of the image goes blue. So let's do this. Let's click OK. And let's make a copy of this visible layer or duplicate it. So I'm just going to do right click duplicate layer. So now we have visible copy. I'm going to go into this visible copy layer and basically bring down the blues in the top part of the image here. So it looks right. There we go. But of course, now that just now we have the same problem in the middle of the middle getting too green. But what we can do is with this visible copy layer, we're going to add a layer mask. So I'm just going to right click and choose add layer mask. And you can leave it on this default initialize layer mask to white. That's fine. And then we're going to add a gradient to this layer mask. So let me grab my gradient tool here. And in the default mode, it goes from white to black. That's exactly what we want. And we want the top part of the image for this visible copy to apply. But down here in the middle, we don't want it to. So I'm just going to drag a gradient from the top to the middle of the image and hit enter to accept that gradient. So you can now see there's a gradient drawn onto the the layer mask on this visible copy. If I turn that layer off and on, you can see what it's doing is it's correcting that really strong blue cast on the top of the image. Okay, there's definitely more that we could do with this, but I'm going to call this good. I really think it looks pretty neat. A lot of detail in the Milky Way and the Lagoon and Trifid. Let's go ahead and save it. So of course, to save in GIMP, we can just do file, save and save in GIMP's default format of XCF. And this way we could return to this and keep messing around with the layers here in GIMP. So I'll just call that lagoon.xcf save that to the desktop. And then to save in other formats, you do file export. And you can just put in whatever ending you want. So if you wanted to save it as a 16 bit TIF, you just leave there. That is TIF. I'm going to save off a jpeg. So I'm just going to do .jpeg. jpeg is good for sharing on social media or online because it's compressed so you can send it more places and it loads faster. I'm going to go ahead and export that. I always export at 100% quality. So as little as compression as GIMP will do. Go ahead and export. And let's go ahead and take a look at our final result here. Okay, it's maybe a little bit over saturated for some people's taste. Maybe I could dial that down a little bit. And then we still have some color cast issues like a little bit too red in this corner, too red magenta in this corner, a little bit too green in the middle and some other stuff up here. So we could continue working on those. I'm using that same tactic I showed you where if you apply a new layer and then apply a gradient mask, you can fix some of these color casts. But for a first start, this is definitely pretty cool looking. This is under 10 minutes, not tracked just on a tripod with my Canon 60D, which is a stock Canon 60D camera and my 50 millimeter Canon lens. Let's go ahead and zoom in a little bit here just to show you some of the details. Another thing we didn't do is any noise reduction. So it is a little bit noisy because it's only under 10 minutes of data, but it looks pretty good. I think some nice detail here in the core of the lagoon, we even have that sort of extension of the lagoon over here. The triphid looks nice. This star cloud looks nice. We have a little cluster over here. I don't remember. I think that's a messy cluster of I can't remember what it called. And then we have the Omega and the Eagle up here at the top. And then of course, really, it's meant to be seen in full like this with the whole extent of these brilliant Milky Way stars, because this is right into the core of the Milky Way. Okay, till next time, this has been Nico Carver from nebulaphotos.com and clear skies, everyone.