 This is an 80 millimeter refractor, and this is an 80 millimeter refractor, and this you may have guessed it by now is also an 80 millimeter refractor. So why does this one cost $130, this one cost $600, and this one cost $1,750? In this video I'll explain why and I'll share everything that you should look out for when buying your first refractor telescope for astrophotography. Hey welcome this is Nico from Nebula Photos. This is a channel all about amateur astrophotography, and I cover everything about that hobby including tutorials, explainers, and reviews like this video today. And since this is a review comparing these three telescopes, I need to share a few disclosures up top here. Both the Ascar ADPHQ and the SV Bony SV 503 telescopes were sent to me by the respective manufacturers, and that was at my request for the purpose of this review. But I'm making this video completely independently, and so Ascar and SV Bony won't see it before it goes live here on my YouTube channel. The Orion Short Tube 80 as well as the mount, the Skywatcher mount, the Sigma FP mirrorless camera, the guiding equipment they used, those are all items I've bought myself for the channel, but with financial support from my generous patrons over on patreon.com slash Nebula Photos. And that support is really what keeps the lights on for this channel, but I'll say more about it at the end of the video. So let's first jump into the design of a refractor and what makes a design well suited for astrophotography. And we will specifically be looking at the design of these three telescopes of course. So the first thing that you want to look for is how many glass elements are actually in the tube, and then how many of those elements are ED glass. ED stands for extra low dispersion and without at least one element being made of ED glass you get a lot of blue, violet or magenta fringing on your stars and that can be really pretty distracting and hard to remove in post-processing without leaving some kind of artifact. Now there are fringe killer or minus violet filters and those can work pretty good for removing it optically, but keep in mind there is no free lunch and with those filters you'll be removing some colors from your photos. So in order to treat the symptom of the problem stars you might get worse color reproduction otherwise. So it's always best if you can afford it to get a refractor with ED glass, extra low dispersion glass. So in my comparison here the Ryan short tube 80 is a doublet with two glass elements but neither have ED glass. This is also a doublet the SV Boney, but one of those elements is an ED glass and FPL 51 and the Ascar is a quadruplet meaning four elements and two of those are ED glass. So two, one, zero. Now another word you'll see that is related to the number of glass elements and the type of glass that they're using is apochromatic or acromatic and this refers to the telescope's ability to focus all the colors at the same time all the colors in the visible spectrum and that's an important ability especially when you're shooting with DSLRs or one-shot color cameras. There's some debate online whether a doublet with ED glass can count as apochromatic an apochromatic telescope. My opinion is really what matters is the images. So if you can take a photo with an ED doublet and not see any obvious fringing on the stars then we should basically consider that apochromatic whether it is technically or not. But of course people will have different standards for this kind of thing and some people are much pickier than others so I'll be presenting a little bit later in the video actual image comparison so you can really decide for yourself what level of perfection you need. But general takeaways here again a refractor with more ED glass is going to give you better color reproduction tighter stars typically and the worst kind of refractor for especially for one-shot color camera is an acromat. Last thing about this is that with a doublet or a triplet you'll typically want a field flattener or a flattener reducer. With this SV bony there's a matched flattener reducer available so I've included that in the price of $600. I didn't see one available for the Orion and with the way this focuser is designed I don't think there are any on the market that would work. Now the Asgard does not need a field flattener because it's designed for imaging and so the corrector is actually built in to the telescope design because it's a quid droplet. But Asgard does offer an optional reducer it's just a reducer only and you know no flattening element but I did use it for these image tests and included it in the price here. So that's a pretty cool feature of the Asgard is that you can use it at 600 millimeter focal length if you want to go at f 7.5 or you can use that 0.7x 0.76x reducer to bring it down to like 450 millimeters. Let's next look at price. I picked these three telescopes on purpose as I think it gives you a pretty good idea of what to expect at each sort of type of telescopes. So this is an acromat not really designed for imaging it's more designed as like a quick go-to scope or guide scope and they started around $100 go up from there. This is an ED doublet $600 with the field flattener is pretty sort of standard on the low end and this is more of like a premium astrograph kind of refractor so 1750 is not unusual they go up from there. There's some that are cheaper but typically for smaller astrographs like a red cat or an FRA 300 so for an 80 millimeter astrograph I think this Asgard is competitively priced. So I'm rather not go really into the discussion of value because I think that's really subjective it's really just about what you're looking for in a telescope. So after watching this whole review I'm just really going to leave it up to you again what level of perfection you're trying to achieve with like the tightness of your stars and how much fringing they have that's the main thing that sort of differentiates these especially these two on the higher end. The one thing I do want to say about price and cost is you really don't want to skimp on the mount. So if you could save money somewhere save money with the telescope and the camera I'd say especially the camera doesn't matter that much but the mount is very important. So for something like an 80 millimeter refractor this one's a little bit lighter than the other two but you could go with one of these like small mounts like I have here like the ioptron Smart EQ but I'd really suggest going up to like a EQM35 HEQ5 and ioptron 726 something like that's going to be better. And I tested all three on my EQ6R again probably overkill maybe but I wanted to make sure that I was just testing the optical performance so I used a very good mount so that there was no problem with tracking. Now let's go ahead and look at the physical characteristics of these telescopes including the weight, the focusers, the build quality and everything that sort of included like the rings or the brackets and things like that. The Orion Short Tube 80 is 15 inches long or 380 millimeters. The Dew Shield does not retract but it's already so compact that it's not really a big deal. When I bought it I remember it just coming with this small Vixen dovetail plate you know bolted on to the bottom but I looked online now and I see there's a bunch of different configurations with different accessories so if I were to get it today with imaging in mind I'd probably get the rings because with this configuration there's no way to rotate. Well if I had rings I could at least rotate the whole scope in the rings and sometimes rotation is very nice to have. In terms of what it comes with it does come with this Cinta style finder shoe built into the focuser. It comes with a plastic cap for the front and the focuser is a single speed it's not a two inch it's and you can hear it makes a little bit of sort of crinkly noise that I associate with low quality focusers it's not perfectly smooth and so the focuser is not a full two inch focuser so you can't use any of your two inch eyepieces or any 48 millimeters accessories with this. This also makes finding a field flattener for this very difficult because all of the third-party field flatteners have 48 millimeter threads on the telescope side but the good thing that they did with the focuser is this is 42 millimeter standard T thread so that means you can just get standard T adapters not the wide T adapters but just the normal M42 T adapters to get your DSLR or mirrorless camera put on to the telescope and I should also say that because it doesn't use any kind of field corrector you can just put your camera on and then as soon as it reaches focus you're in focus there's no there's no worry about particular back focus with with this telescope. The focuser does extend quite a ways as you can see but you could also put on spacers as if you need it even more back focus travel but I've had no problem with getting into focus with the Orion Short Tube 80 and the telescope has a focal length of 400 millimeters and a focal ratio of f5 which is printed right on the scope right there. Let's move on here to the SV Bony SV50380ED. It's close to around 18 inches or 450 millimeters long with the dew shield retracted and then with the dew shield extended it is about 24 inches or 620 millimeters long. The weight with the field flattener reducer installed back here is around 6.6 pounds or 3 kilograms so not heavy by any means but also not super light like the Orion was. It comes with very nice rings with nice big knobs as you can see for loosening and tightening and it also has a vixen dovetail plate installed on the bottom. It comes with a metal front cap and it doesn't actually come with a synthestyle finder shoe. I installed that afterwards. I just got this off eBay but it does come with plenty of places to put one if you so desire but it doesn't come with this so this is be something you have to add. It has a very nice two speed focuser. There's the course and there's the fine and it works very very well and it's very smooth so I've had no problems with that and it does offer full 360 rotation on the focuser. You just loosen that knob right there and then you can rotate the focuser and then tighten it back up. You see the focuser does have gauge markings in millimeters so that's nice for repeatable focus. In terms of installing the Field Fladdener it has these three thumb screws that have a compression ring inside here and then the Field Fladdener simply slides in to the focuser like that which works fine and then the Field Fladdener itself has normal 48 millimeter thread on the camera side. If you do plan to get this telescope again this is the SV Boney SV503 I'd highly recommend getting this 0.8x photo reducer and Field Fladdener because that's going to make the stars a lot better and with the reducer it comes down from 560 millimeters f7 to 448 millimeters f5.6 which is a very nice focal length and ratio for lots of deep sky targets. Alright so that's the SV Boney SV503 80ED in terms of its physical makeup. Okay and finally we have the Ascar 80PHQ Q4 Quad and this one is in a fairly new line of quadruplet telescopes from Ascar that all have long native focal length for their respective aperture so this is an 80 millimeter scope but it's at f7.5 600 millimeter focal length. But then you can also get a 0.7x times reducer for it and that brings it down to 456 millimeter focal length at f5.7 and what's really cool about this line of telescope and the reducer is that both the native focal length and with the reducer you're corrected for a full frame sensor and so that's actually fairly rare in a telescope this price point that it would be well corrected out to full frame. So that is the big reason why this one is so much more expensive than the SV Boney. This one's 1,750 SV Boney is 600 is because of that being able to have it really meant for full frame imaging. Okay with the dew shield retracted like this it's about the same length as the SV Boney 18 inches long or 450 millimeters. With the dew shield extended out it's just a little bit shorter than the SV Boney it's 22 inches or about 570 millimeters long. The weight of this scope with the reducer is 10.6 pounds or 4.8 kilograms which is fairly heavy for an 80 millimeter refractor but quads are always heavy for their size because there's big glass elements and there's four of them in this while there's only two in the other two telescopes I showed you which were doublets. And then also the reducer itself adds a couple pounds since it's a three inch reducer so that's a fairly large reducer. The telescope comes with very nice rings with tons of tapped holes all around and a nice long green dovetail plate fixed in style. It comes with this top handle that I've been using to manipulate the telescope. It's a metal front cap with the name of the telescope on the front and then one thing that is really cool which I've never seen before is it comes with not just one but four different options threaded connections for connecting your camera or your spacers or whatever you're using. So let me show you how this works. So each of these back here is another threaded connection. We have M76, M68, M54 and M48. So all kinds of different threaded connections are included. You don't have to go out and find those if you have a specialty connection that's needed. This is the reducer, the 0.7x reducer. And I just want to show you how this goes into the telescope. You use this stack of threaded connections that comes with the telescope. You thread the reducer in here like that and then the whole thing slides perfectly into the focuser and then threads on to the back of the telescope. So I thought that was a really neat design to have the reducer have a threaded connection into this adapter that then threads onto the back of the focuser. And there's diagrams included showing you how to use all these different adapters. Since it is a quad, if you use it without a reducer, you can just attach your camera to the back here and just come to focus. And as soon as you're in focus, you're good to go. With the reducer installed, you're going to want 55mm back focus. In terms of markings, this both has markings for focal distance, but it also has markings for the rotator, which is really handy. I wish all telescopes had that. So it's a 360 rotator and it has every degree marked right there. It comes with one Cintiff style finder shoe standard, but it also has a place for another right there. You could easily install a ZWO EAF or other electronic focuser and there are already mounting holes. And lastly, I'll just say this is a very substantial three inch focuser that feels nice and sturdy and quite premium. It does have two speeds, of course. Okay, now we're on to my favorite part, which is actually looking at the images and doing some comparisons. Before I launch into that, let me just show you the stats of this imaging session. So I was shooting the Iris Nebula from Portal 4, the moon was new. I waited until the Iris was very high up in the sky, which was two to three AM, which is also the darkest time, I think. And then I was using a Skywatcher EQ6R, which is a nice beefy mount, so no problems with tracking. But just to make sure I was also guiding with a William Optics Uniguide 50 millimeters and an ASI 290mm mini. I was using a Sigma FP full frame mirrorless camera. It does not have a low pass filter, but it was not modified. So it's a very good camera, I think for testing for these kinds of things, because it's going to have a nice sharp image without the low pass filter to really give us a good indication of the optical quality of these telescopes. I was shooting at ISO 1600 and for each telescope, I took four by four minutes in terms of exposure. So you know, I could have tried to take more, but I wanted to really limit it to just like one part of the sky as quickly as possible to try to keep the bias from changing sky conditions out of this as much as possible. So I did it all within an hour by moving very quickly. Okay, so first let's look at just some raw frames, highly stretched with the auto stretch. And the point of this is really just to look at what a single four minute raw looks like and how much vignetting is affecting the image. There is some shadowing of the corners vignetting in all of these images. This is the Orion short tube 80. There's the SV Bony SV 503. And then here is the Ascar 80PHQ. And the way that it vignettes on the Ascar is interesting. And I'm not sure. I'd be interested to try it with another full frame camera just to make sure that it's not some quirk of the Sigma FP that's creating this kind of vignette. I'm not really sure, but it does look sort of odd. These ones look more normal. But then the next question of course is, well, how does that calibrate out with flats? That's what the Orion looks like after I calibrated with flats, darks, and bias. Here's the SV Bony a bit better. And then there's the Ascar a bit better still. Now I'll get to this more as we go. But the SV Bony isn't correct or isn't really designed for full frame. So you know you can sort of see that that it really sort of corrects out to about there and then sort of there's some weirdness. While the Ascar is a full frame corrected telescope and the reducer is also for full frame. And the Orion we have no field corrector. So we really only have a small section here in the middle that has sharp stars. And then it very quickly gets sort of crazy. And just to show that another way here is just the corners and the center. So you can see the center of the Orion is quite sharp. But then in the corners it's pretty bad. The SV Bony is quite a bit better. But if we look out into the corners of a full frame sensor, you can see we have triangles instead of round stars. While with the Ascar, they are still quite sharp and quite round. And so I've emphasized this I think a number of times. But that's what you're really paying for with an astrograph like the Ascar is the ability to get fairly round sharp stars all the way out into the corners of a four frame sensor, which you're not going to be able to do with a scope that's more like $600. But you could just use a smaller sensor with this telescope and it would work quite well. Okay. And then this next set is well how we saw what it looks like with just calibration. It looked like that. But then if we run a dynamic background extraction, how does it look after that? And you can see the Orion gets quite a bit flatter as does the SV Bony. And the Ascar looks perfect. I mean, that's a very flat field with really no problems there. Okay. And then this is just that same picture we just saw about without the stars and it shows you that the SV Bony is corrected. You know, this this doesn't look like quite APSC maybe maybe just a but pretty close to APSC. And then the full frame part is just not corrected at all. And we're getting a lot of light fall off out there. Same thing with the Orion Starless, the DBE seemed to work a little bit better though. Or maybe it's just a stretch them differently. And then here's the Ascar. Again, pretty flat. Okay. And then here is the maybe what a lot of people have been waiting for. Here's my final images as I would process each one, including the crop. So with the Orion I'd crop quite a bit in just to that sort of central portion. So again, here's the full Orion frame and I'd cropped basically right into the center to avoid all of these weird stars out on the corners. But after you do that, it looks pretty good. The one sort of thing that stands out about this image, well, two things actually one is we get all this sort of violet fringing on all the bright stars. And then the other thing is we're not getting a whole lot of color on the iris. And I did try to bring it out and I'm still just not really getting that sort of cool blue reflection nebula color. I'm not sure why. But we do get some of the the dust around the iris. Here's the SV bony. And again, I cropped down. It's probably around a PSC, but it's a little bit squareer than a PSC is what I just I did a pretty lazy crop. I didn't try to correct this ring. So I really just took a crop and went boom, boom, boom, boom, and cropped like that to get this. And then here is the Ascar and with the Ascar I could use the full frame. Now I might still crop this down because this was just a very short integration. So there's not a whole lot going on yet. But if you imagine if I shot this for several hours, this whole frame would fill up with that beautiful dust and CFIUS and it would look really cool. Okay, and last comparison, I just cropped in to the center of each one and registered these together just to show you sort of the deep, you know, the detail difference and the sharpness difference at the center of the frame. If that's something you're you're interested in. So I don't know how clear it is. It's clear to me that the the Ascar is sharper than the SV bony. And then it should be clear even to everyone that they're both sharper than the Orion. But let me actually zoom in a little bit just to really drive this home. Pick some pick a star field that has sort of a mix of smaller stars and bigger stars that looks good. Okay, so this is pretty illustrative of what you're getting for 130, 600 and 1750. So you can see there's a pretty dramatic difference here between the 130 and 600 we drop a lot of this sort of ugly fringing around the stars and we get a huge sharpness increase, because you can see all of these dimmer stars that are basically invisible with the Orion. Now the difference between here and here, you can see is much more subtle. The stars are a little bit sharper. But really the big thing that you're paying for is not the the center sharpness getting so much better. But the fact that the corners and full frame are so much better. Because see here you get the triangle stars here. The corner stars are almost as sharp as they are in center. So that's what's so impressive. And that's why you pay more for a scope like the Ascar. Since this video is over 20 minutes long, you're now seeing all of my current members on Patreon. If you want to see your name in the credits, you can sign up over on patreon.com slash Nebula photos. It starts at $1 a month and signing up has a bunch of perks outside of your name in the credits, including exclusive videos, monthly zoom chats, a really awesome discord community, monthly imaging challenges with prizes, group imaging projects, other competitions to win gear, and of course a direct way to message me with your comments and questions. So if you like my videos and you want to accelerate your learning, consider joining there for as little again as $1 a month or there's also a $3 a month here and a $7 a month here. And again, the link is patreon.com slash Nebula photos. Till next time, this has been Nico Carver, Nebula Photos, Clear Skies.