RASA vs Quattro - Comparing results! (Could be time for a change?)

This is not an apples-to-apples comparison, regardless - it's fun to do, so here it is!
A small comparison data set I've been putting together between my two main scopes, the Celestron RASA11 and Skywatcher Quattro 8.
www.firstlightoptics.com/telescopes-in-stock/skywatcher-quattro-f4-imaging-newtonian/ref/lukomatico
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#astrophotography #space #stars #nebula #pixinsight #seestar #zwo
00:00 start

[@ross1972]

Your really asking big questions and coming up with surprising answers. This will definitly influance what I spend my money and time on in the future. Clearly the Quatro for the win. We are living in the golden age for Amature Astronomy, and your making a significant contribution.

[@amrikarim]

💯agree! This got me to reconsider "upgrading" from a Quattro 8" to RASA 8

[@lukomatico]

Hey mate! That's lovely to hear, I'm flattered that you feel that my work on this kind of thing has value - thank you! 👍 It's certainly been a thought provoking experiment for me, and really got me questioning my scope lineup, definitely we can say that 'more expensive' doesn't always automatically equal better! Clear skies!

[@lukomatico]

That's great mate! The rasa8 is tremendous in it's own right, but man, the quattro is capable of far higher resolution! Cheers for watching!

[@tubedude54]

@@lukomatico Given the same size objective the only other thing that affects a scopes resolution is the wavelength of light... I have to assume you used the same camera configuration so then something else is affecting the differences we see here... could it be the corrector plate somehow?

[@CuivTheLazyGeek]

First? :) And huh, Quattro for the win... More details but also more native contrast. And fewer headaches for narrowband filters and bandpass shift considerations... What NB filter did you use for each?

[@d.fresh.750]

Damn you, Cuiv! LOL!

[@lukomatico]

First indeed hahaha!! :-D (For anyone reading this: imagine having one of your favourite creators across the whole of YT commenting 'first!' on your channel vids, I feel like I'm living in some kind of dream haha!) All great points mate, agreed! - the Quattro takes the win! - I was using the best filters I had on hand in each situation, so for the UV/IR comparison a Baader L on the RASA, vs Astronomik L on the Quattro, and for the dual-narrowband comparison it was an L-extreme F2 edition for the RASA, and Player One anti-halo pro for the Quattro! Cheers! :-)

[@lukomatico]

Haha!! he's too darned fast! :-D

[@astromatt75]

Great video. Love how informative your content is, Luke!

[@lukomatico]

I appreciate that a great deal, honestly! - Thank you! :-)

[@mickwhitaker4086]

I’ve just about tamed my Quattro 150p f.3 ish, it is now becoming my go to for imaging in either Dual Narrowband or Mono. I hated it when I first purchased it but after a few little changes and modifications I’m beginning to love it.

[@lukomatico]

Superb to hear it mate! - it's a really capable scope isn't it! I know Cuiv's been loving his one! :-D Hope you've been getting out and enjoying it!

[@chrisharrison610]

Great work Luke, its never a waste of time if you are learning something new. Keep up the awesome work

[@lukomatico]

Thanks so much mate!! Glad you enjoyed 👍

[@Jcorban08]

Another awesome video, Luke! It was very informative/helpful to see the side by side comparison. I wonder if the fine tuning (flocking,etc) would go smoother for the Quattro. For sure it has a sweet price point! Take care, looking forward to your next project(s)

[@lukomatico]

Thanks so much mate and I'm sorry about the late reply! had a heck of a few days lol! It's a good question you raise by the way, I think a newt is definitely easier to fine-tune than the RASA, so I wonder how much further that would skew the results? interesting! Clear skies :-)

[@enriqueboeneker]

Hey Luke! Thanks again for this video. Have to say that the Newt is all me! I bought myself the cheaper f/5 version of Sky-Watcher and have to say I’m loving it, even with no modifications (like flocking, painting focuser’s tube, etc.). Cheers, my friend!

[@lukomatico]

Cheers my friend!! the f5 SW newts are brilliant scopes :-) really glad to hear you're having a good time with it!!

[@AstroLaVista]

Always learn something interesting from your videos Luke :)

[@lukomatico]

So kind of you to say that mate!! I'm flattered haha! Thanks ever so much for your support!

[@samuelandrew4500]

Interesting result, good to actually see the real differene in resolving capability demponstrated, surprised there isn't more difference in the noise levels. The Quattro's are great scopes.

[@iamjessieray]

Another great video! I think what this really illustrates outside of the pixel scale is that if someone can't fork over the cash for a RASA, the quattro is a fantastic scope. I use it's cousin the 130p-ds and get great results with it so it makes me wonder if one day I might also get a hold of an 8" quattro

[@lukomatico]

Oh mate I couldn't agree more!! The 130pds is absolutely tremendous, so much potential in such a great priced scope :-)

[@avt_astro206]

Impressive pictures! Very Good comparison man!

[@lukomatico]

Thanks a lot Avanteesh!! I appreciate that mate 🙏

[@romaindechamps457]

This is the second test with Cuiv's one that shows clear sharpenes advantage over the newton, thank you for confirming this trend!

[@lukomatico]

Thank you so much for watching mate!! 👍👍

[@peterwebster2555]

Great video, very interesting to me, as I have both of these telescopes, Quattro is a 10CF! I suppose, in my mind, for a comparison at the same resolution, use drizzle to match the resolutions, or swap out the camera on the RASA for something like a ZWO 294 MM/MC based chip at BINx1 @ 2.3 micron pixel size (not certain you can bin at x1 on the MC version) and run the same test! Very compulsive viewing this Luke, massively appreciate that you take the time to do these comparisons. As always, great stuff, please keep it coming!

[@lukomatico]

Hey Peter! - so sorry about the late reply to this, not sure what happened! I'm really glad to hear you've been finding these kind of videos interesting, that's superb news! - You make some great suggestions there too, if I revisit this I'll be sure to do a more thorough investigation - that said, the RASA is coming off the mount for a little rest from tomorrow onwards, I've got something else to test! Clear skies!

[@peterwebster2555]

What a tease!! Now really looking forward to your next video! Also regarding the test you did here, the RASA would of collected, theoretically, x3.3 as much light as the Quattro F.2.2 vs F4 for the same imaging time, the results you got in your final images really disguise that, especially as the Quattro was at 0.75"/pix vs 1.25"/pix on the RASA AND I bet it was loads easier to deal with the tilt on the Quattro!?@@lukomatico

[@tezza0905]

I don't use a RASA but I've a fast Newtonian (SharpStar F/2.8 and FL of 420mm) which gives great wide fields, but the pixel scale is coarse with my 294MC-Pro. Following something I saw from Russ Croman, I've started drizzling to upscale the results which means that BlurXterminator works better and I'm happy with the results. Your RASA will collect photons at around 4 times the rate of the Quattro so collecting enough frames to keep the noise down after drizzling shouldn't be an issue. Might be worth a try.

[@lukomatico]

Hey mate! - You're totally right, that would certainly be a strategy I'd use to try and close the gap between them a bit, well noted! :-) I decided for this little comparison to just leave everything as 'natural' as possible though, so no drizzle/resample work, - hope that explains my reasoning! Cheers! :-D

[@Astrobloke]

Great video Luke, I am really surprised at how much of a difference there is and considering the difference in the price point of the 2 scopes a little shocked. As you know I am a big fan of Newtonians and have always loved the sharpness of my CT10 (without doubt the best scope I have) Keep up the great work mate and of course clear skies.

[@lukomatico]

Hey Glenn! Hope you've been doing well mate :-D it's a pretty notable difference hey, can't knock the good old Quattro! I do love the RASA still for that speed on the really faint stuff, but it gets me thinking to be honest 😅 Thanks for watching mate!

[@barrytrudgian4514]

The Quattro is really cool. I jumped straight from Canon 100-400 to the Quattro 250. Steep learning curve but rewarding. I've also found Russell Croman's Exterminator tools extremely useful, although my first step in post processing is always Graxpert. Keep up the good work on your channel.

[@lukomatico]

Thanks ever so much Barry! That's quite the leap you made in terms of lens/scope by the way! Good on ya for getting stuck in there mate 👍👍

[@DinoDematteis-wx9ou]

Great comparison video Luke, as some of the earlier comments stated, re-testing with the cameras swapped would be great! I have been debating buying the Quattro but I've also considered the RASA.

[@lukomatico]

Thanks so much mate! I agree, that could be an interesting comparison method!! :-) I'll have a look into doing it 👍 clear skies!

[@DSOImager]

Never a waste of time! Comparisons like this are fun to watch while also yielding good datapoints. For me the Quattro definitely looks better. I wonder if the difference in details/contrast is due to the smaller (I assume) central obstruction of the newt. Another test may be in order.. I'd like to see how the two compare on a really faint target.. the Squid nebula (Ou4) for example or the medulla nebula (CTB-1). Would be interesting to see if the F2 speed makes up for the softer details with raw speed. Clear Skies!

[@lukomatico]

Hey there James! - Hope you're well mate :-) You raise interesting questions, as always! :-D I think the difference in contrast could be down to C/O as you suggest, or perhaps even down to the fact that the quattro has main-tube ray traced baffles, so it should be pretty dark in there without much light bouncing around off-axis! - the inside of the RASA is just a kinda dark grey, odd! It'd be cool to test on a fainter target for sure, or even swap the cameras around too as a few have suggested and try that also - if I get a good string of clear nights it could well be worth a look! Clear skies my friend!

[@ATOMSCOLLIDE]

Good comparison and informative. Would love if there was a link to download the original data to pixel peep. Being that the RASA has the wider FOV a equal crop ratio on both would also be interesting to see side by side.

[@buggyland]

Cheers Luke, great comparison. Can you do a follow up where you've swapped the cameras for completeness?

[@lukomatico]

Hey mate! - That would be a pretty interesting comparison to make aye, thank you for the suggestion! if it looks like enough people want to see it then I can do it I'm sure! :-) Clear skies!!

[@luboinchina3013]

Man, this video is going to hit RASA sales hard. I guess Skywatcher is going to send you more juicy telescopes to try. I would like to add another comparison - Quattro vs Refractor priced at RASA11 range.

[@lukomatico]

That would be a really interesting comparison Lubo! :-D I'm really glad I bought the Quattro, but maybe one day Skywatcher will want to send over an esprit 150 for testing haha! A man can dream! :-D Clear skies mate

[@luboinchina3013]

@@lukomatico I just received my SeeStar today and strangely enough it is clear outside, so I am trying it out in my local park at the medium light polluted town. Cannot compare to a real astrophotography gear, but it is so comfortable to just sit and enjoy the night😊

[@testboga5991]

That Quattro is giving great images!

[@SimonsAstro]

Hey Luke, interesting video mate! That’s quite surprising and good to know that a much cheaper scope can produce such a good quality image! Much more in my price range😀 Thanks for sharing Luke Clear skies!

[@lukomatico]

My pleasure Simon mate!! :-D The quattro really packs a punch!!! As always, thank you for watching and supporting!!

[@azrayastrophotography2260]

Hey Luke nice comparison with the two scopes. Thanks for the great information. I have the same scopes so maybe I'll try some comparisons with my skies to see what difference I find. Clear skies.

[@lukomatico]

That'd be really interesting to see Ray, location could indeed have a lot to do with it!! Hope you and your wife are well my friend :-)

[@azrayastrophotography2260]

@@lukomatico yes I am going to compare as close as possible at the same image scale. I'll send you the results. It may take a couple of days depending on the weather of course. Cs

[@gabewrsewell]

great comparison luke, thanks for sharing! personally i image with a 400mm f/2.8 lens with a 24 megapickle full frame sensor, as i’m an absolute fiend for those dark nebulae and light collection in general. i’ve also been feeling a need for finer resolution lately though, and that comparison has helped fuel that so thanks :) you know what they say, the easiest way to make money as a photographer is to sell your gear, maybe i can look for more stuff to sell and pick up a nice newt or sct if i feel like imaging galaxies. thanks again! :)

[@lukomatico]

Hey mate! I totally hear you haha, there's a certain allure to the finer resolution work for sure, it's something that I've been wanting to do again for a while - as you say, it may be worth looking to get a nice newt or sct and then you've got the option for that! :-) Clear skies!

[@kanellosdimitropoulos9759]

Why not switch cameras and make it a fair ~1" per pixel for both scopes to compensate for FL difference? Ofc there will be a difference in details when one is sampling more than 50% higher than the other... Contrast wise the difference is obvious and expected but detail wise it's not a fair fight imo.

[@lukomatico]

Hey mate! it's definitely not a fair fight yeah, but I do state that a few times in the vid :-D It's more a 'just for fun' look at my two scopes as they are currently setup in order to help demonstrate the differences between the two pixel scales (and other differences with the scopes of course) - All that said, it could be interesting to compare the two with the cameras swapped though anyway! If enough people want to see it then it's something I can look into doing! Cheers!

[@desbarry8414]

Ive never understood the rationale for the RASA 11, clearly the larger aperture is more affected by seeing conditions. Glad Ive got a C925 and new Hyperstar rather than a C11. Great video Luke.

[@lukomatico]

Thanks so much mate! - I guess with the RASA it's fast & wide which is a pretty challenging combo, for its intended purpose it's incredible - but for max resolution work, there's certainly more suitable scopes! Clear skies :-D

[@flyingdockp]

It would be even more interesting to see the results of this test with different pixelsize on the same telescope But these comparisons shake things up for sure!

[@lukomatico]

I'm glad you enjoyed it my friend! And I agree, going further with the test would have been beneficial! :-D

[@Alan-vk6bk]

I think youve already made your mind up. Im loving imaging with my RC8. High resolution is tough but rewarding. You have the right mount and the experience to pull it off im sure....

[@lukomatico]

Thank you mate! I'll hopefully have a more clear picture of how I'll go from here soon, plans are being made! 😅

[@Alan-vk6bk]

@@lukomatico can I ask a big favour?? Would you be able to 3d print me a primary mirror mask for my newly acquired 150 PDS?

[@lukomatico]

@@Alan-vk6bk absolutely mate, no problem

[@lukomatico]

@@Alan-vk6bk let me know your measurements required etc and I'll get it figured out :-)

[@Alan-vk6bk]

@@lukomatico I've tried to reply. If you search 150pds on Google there are sites with downloadable files...

[@goldfish31ful]

I image with the 8" Astrograph. Love it!

[@lukomatico]

Great to hear mate!! :-D clear skies!

[@Infinity_Focus]

Hei Luke, thanks for the great and interesting comparison. I'm kind if a RASA fanboy, even if I don't own one (yet). What would have been nice to see first is the overall FoV. Obviously there is a difference in focal length, so it's not very surprising that the quattro will give you a little bit of extra resolution even at a smaller f-number (+the smaller pixels). However, I'd have expected the difference in noise be more dramatic. How long was your Integration time on both rigs? Were the subs the same size? Thanks man!

[@lukomatico]

Thanks so much for watching mate! I can't remember the sub exposure details on these stacks, my apologies!

[@Demon-tp3bs]

Great vid Luke, unless my eyes are playing tricks the right hand galaxy field image from the Quattro has duplicate stars - so looks like some dodgy images may have crept into the stack where presumably the scope has moved - which would make the comparison even more greater in favour of the Quattro. Its a very interesting comparison as I have a 16" F4.5 on an EQ fork mount which is just starting to produce results and apart from the shear length and bulk where the Rasa is more forgiving v's wind etc, its nice to know that your slightly slower newt wins optically. Thanks.

[@lukomatico]

Hey there mate! You're absolutely right, there were indeed a few bad frames that crept into the stack - good eye! 👍 Your 16" is going to create some truly stunning shots I'm sure, what a tremendous thing to own and use that must be! :-) Thanks for watching!

[@backyard-universe]

With some modifications, the Skywatcher Quattros are amazing telescopes! I modified my 6” Quattro and run it @ f/3 and this telescope is very close to a TAK160ED in imaging performance! All modifications I made was to replace the steel tube by a velours lined carbon fiber tube, replacing the sheet metal secondary spider with a cnc machined , add a primary mirror mask and made some modifications to the primary mirror cell. The total cost for such a modified telescope is still only a 1/3 of a TAK or RASA11……skywatcher ms are definitely a good point to start! Let me know if you want to test auch a cnc machined spider and a primary mirror mask 😊

[@lukomatico]

Hey there my friend! Sorry about the late reply to this, I totally agree haha - with a few mods the scopes can be absolutely incredible performers :-) I'd love the opportunity to check out some of your mods sometime, thank you ever so much! :-) Clear skies buddy!!

[@tubedude54]

I almost popped for a C14 with hyperstar when they came available a few months ago and I'm kinda glad I didn't. It looks now like I will be going with an 18" F4 newt (not a dob) for about the same price and your videos and others doing similar videos have me thinking I'm making the right choice.

[@lukomatico]

Oh mate, that'll be a monster!! I can only imagine the size of the mount you'll be putting it on haha, - I do think it'll be a heck of an instrument though if you do go that route- lots of fun ahead either way! Clear skies!

[@jasonpatterson8091]

I personally enjoy imaging the finer details of the sky as opposed to the larger nebulae. They both can be beautiful and skillfully captured, and of course, I think that people should go after the thing that pulls their mind and heart the strongest. That said, of the two, the Quattro is the clear winner for these particular targets at the scales you've shown. If you're trying to capture smaller objects and finer details then there's not much of an argument to be made for the RASA. At the same time, if you want that big, sweeping nebula all in one image, a RASA is just incredible. Different tools for different jobs, you know?

[@lukomatico]

Very well said indeed Jason! Couldn't agree more with your summary mate :-) I think right now my desire is to go after some smaller regions/targets as they captivate me without fail, so I think I'll have to make it happen! :-D Clear skies to you!

[@GregZuliani]

It would be interesting to resample the quattro image to end up with the same image scale as the RASA. This way you could tell if the difference is down to the focal length/smaller pixels or if the quattro is a sharper scope.

[@lukomatico]

Thanks for the suggestion Greg! - Likely more comparison videos to come!

[@ssrattus]

Small pixels FTW, thanks Luke.

[@lukomatico]

Thank you for watching! :-)

[@sevenskiesastro]

Nice little experiment Luke. Did you use a coma corrector on your quattro? Keep up the great videos.

[@lukomatico]

Hey Rob mate! - yes indeedy sir, it was the Aplanatic one for SW newts :-) (I believe you recently showed this on your channel too right?)

[@sevenskiesastro]

@@lukomatico yes that's the one. Excellent bit of kit. Clear skies bud

[@JoMoJack]

Just did first light on my Quattro 8” last night (no clouds on a scope unbox night must mean I should have gotten a lottery ticket instead). Still lots to go with automation in terms of matching my refractor, but even with manual focusing and no guiding, I was supremely amazed with the results. Have you done any modifications on the Quattro yet? I’ve watched Quiv’s series on the 6”, but hardly anyone had gone that deep in the (slightly different) 8”. Would be nice to see what all you’ve done. Great content as always, and thanks for helping with my confirmation bias 😂

[@lukomatico]

Hey mate! So glad to hear your first light went well with the Quattro!! :-D I've heavily modded newts before with 3d printed parts etc, and it made a huge difference for sure, I'll probably get around to it with this quattro also eventually - might make for a few good videos! :-) Clear skies!

[@petesastrophotography]

Taking any image is never a waste of time, so no issues there🙂Excellent comparison Luke, very impressed with the Quattro images. Bit of a hypothetical question but...if you had to chose between the RASA and the Quattro to have as your one and only scope, which would you pick? I know it isn't an entirely fair comparison but given the price difference between the two I think it makes for an interesting question.

[@lukomatico]

Hey Pete! Thanks so much for the lovely comment as always mate, you've asked a really quite thought provoking question there! If I really think hard about it then knowing what I know now, I'd probably keep the Quattro and bear the loss of the RASA while wiping my tears away with all the £20 notes I'd have as a result 🤣

[@peterlaubscher3989]

I have the Quattro 10" - gives stunning results. I had to find 30kg of counterweights for my EQ5 mount, but the EQ5 is able to guide this scope for close on five minutes without trouble, unless the wind is blowing, as it often does in the Cape :( Huge storms in Cape Town this week. [Got the Quattro for a very good price and decided that it was worth the risk on the EQ5 - so glad I overcame my doubts - and my bank manager's complaints...

[@lukomatico]

Great to hear that mate!! I've had a few quattro 10's, they really are great scopes so good on you for getting it up and imaging using what you have to hand! Hope the winds calm for you soon! Clear skies 👍👍

[@mashpotatomountainobserver3338]

That group of galaxies looks like the Deer Lick Group. I just shot it last night with the Uranus C camera and a 130PDS telescope. This setup has a Dawes limit of .89 and I'm shooting at an image scale of .91 Very sharp everytime with details so fine the picture needs to be viewed on a big moniter rather than a phone or tablet. Once again very informative video

[@lukomatico]

Hey mate! sorry about the late reply, - It is indeed the deer lick group! :-D So glad to hear you're still enjoying your rig every clear night mate, that's really brilliant news :-) the best rig is the one you use the most eh! Clear skies to you!

[@Tony-Elliott]

Hi luke great comparison .the Quattro wins hands down mate which is great for us all on a budget

[@lukomatico]

Totally agree Tony! It's certainly food for thought!

[@MrPedalpaddle]

I didn’t see you mention the exposure times for the 2 scopes. In the same total elapsed time, RASA should be able to take more shorter subs & get a better S/N ratio? I should say that I tried & sold my 8” Hyperstar setup & am now very happy with an 8” Newt, but I have split the difference & image @ f/3 with the Nexus Coma corrector.

[@lukomatico]

Hey there mate! :-) in all cases it was 2m exposures, hope that helps! Glad to hear you're enjoying your newt by the way, those starizona nexus correctors look good!

[@liviulazar9387]

Very clear, a Newtonian is always better than an SCT or RASA.

[@lukomatico]

Unless pure speed is your concern!! :-D mostly though, I agree!

[@jakublieder]

Hi, I'm a RASA 11 owner. The problem is that the resolution of 1.25"/pixel +/- is the limit where the stars look undersampling on any telescopes. The problem is compounded if you are using an OSC camera. The Bayer matrix cannot accurately determine the center of the stars, which are more blurred than when using a mono camera. RASA was designed for wide shots of the night sky, and it is 620mm focal lenght. I use drizzle and it helps to get better results when using BXT. I'm resampling the image from 1.25" to 0.8"/pixel and it's much better. If everything is done correctly, I get similar results even with larger telescopes where the limit is in seeing. Sorry for my English.

[@lukomatico]

Hey there my friend! :-) Thank you for watching the video and offering great feedback, it's very kind of you! 👍 I often would drizzle the RASA's data, but bit for the sake of comparison I wanted to keep the data as native as possible for both telescope setups I run, hope that explains my reasoning behind it! 👍 Clear skies :-)

[@jakublieder]

Hi @@lukomatico Okay, so what if you switch cameras? Poseidon on Quattro - pixel scale 0,97" and Uranus on Rasa - 0,96". I think it says more about the resolving power of the optics if the pixel scale is the same. I think the best sampling is about 0,8"/pixel. I look forward to more videos :)

[@lukomatico]

That could absolutely be a future experiment 👍👍 thanks for watching!

[@Seanjones1990]

quattro is the new best scope overall now they have a 6" too with 520mm focal lengh it makes 70/80mm refractors look bad .. the issue of collimation is just another skill people in astrophotography should learn. once its close its only ever a moment to sort correct it with a laser. - recently got my 6" f3.45 quattro the resolution is mad different to a f6 70mm refractor, then add the 3x less exposure time for the same result.. perfect

[@nikaxstrophotography]

Quattro kills it for me Also I like how there are very few diffraction spikes, did you do something to the scope?

[@lukomatico]

Thanks so much Nik! - RE: spikes, the quattro's got very thin secondary mirror vanes, so the diffraction spikes on fainter stars are only slight - if I imaged something with a really bright star in the field of view though then you'd still see big diffraction spikes of course! :-) Cheers!!

[@jimwaters304]

Very useful video. What coma corrector did you use on the Quattro?

[@lukomatico]

Thanks Jim! - I used the skywatcher Aplanatic CC :-) Sorry about the late reply!

[@SKYST0RY]

The Quattro really does wonders, doesn't it. I've been contemplating picking up a Quattro 6" or 8" in the near future, as I begin planning the building of the second observatory. Are you having much trouble with the Quattro dealing with dew or dust build-up?

[@lukomatico]

Hey mate! - good question! Dew is never really a huge concern as long as you're using heaters (wouldn't advise trying without, always went badly for me), but dust is a continual issue!

[@harveyrichard2007]

Luke, you're saying that, in some ways (with the obvious caveats), the 8" f/4 gives us more resolution than a 11" f/2.2?

[@lukomatico]

It does indeed seem that way yeah mate :-) the finding is in line with what you might already expect, but it's still quite stark to see that theoretical difference appear in reality! Clear skies!

[@Phenolisothiocyanate]

If you can do mono on both you should try shooting L frames with the Quattro and NB on the RASA then combine in post. 😊

[@lukomatico]

Could be fun mate!! :-)

[@thevelourfog5422]

I'd love to see the results of the uranus paired with a 250/300pds if you still have one. Im an oag away from this setup myself so until i can get one it would be great to see someone far more skilled try it first 😅

[@lukomatico]

Hey mate! - Unfortunately I don't have the 250 & 300pds anymore, they went around a year ago when I got my observatory setup as they were just a little too big to safely use in here without the chance of collision! :-( All the same, I think when you're set up it'll be a ton of fun and a very powerful rig!

[@thevelourfog5422]

@@lukomatico no worries mate, appreciate the response 👍

[@dumpydalekobservatory]

Interesting comparison mate if you're bored of the RASA I'm sure I could look after if for you as its a V2 so autofocus can work lol. I don't know if focal lengths could change anything as the Quattro is 800mm & the RASA 620mm, also you are looking through more glass with the RASA so maybe that's something to consider to. How about trying identical cameras on both rigs say the Uranus C (If you still have it) as you used to image with one on the RASA 8 & use the pro version uncooled on the other rig? I know my RASA has been a pain but I'm pretty happy with it when it's dialled in & comparing it with My Newtonian at f4.8 there's no contest between the two. Anyhow I really hope this weather changes soon as it's been pretty dire lately, clear skies!!

[@lukomatico]

Hey mate! :-D sorry about the late reply, I don't know what happened here! I'll be honest, the RASA is coming off the mount for a bit from tomorrow onward, going to be testing something else out instead! :-D should be some interesting times ahead! I'm hoping the same with the weather, but we do have a named storm on the way at the minute so I'm not holding my breath haha!

[@anata5127]

One scope PlaneWave 17” and another ASA uwf300 (or Epsilon 160 ED) and you are set.

[@lukomatico]

Hey Ana! - That really would be a supreme combination, I'll not likely be able to afford anything like that but a guy can dream I guess haha! :-) Thanks for watching!

[@anata5127]

@@lukomatico You never know. Some people join a variety of programs and have access to such scopes. Some people get such systems as a part of educational programs. Overall, Rome is not built in short period.

[@CDigata]

interesting thoughts

[@lukomatico]

Thank you Chris mate! Hope none of this was offensive as I know you're currently Mr. RASA himself haha! :-D

[@CDigata]

@@lukomatico not at all. you did say Wazza did you not..

[@tomatomaeg]

How do you reckon the "slower" Quattro data would do if it had lets say the 4nm Altair Astro duoband filter and the RASA system would be restricted to a 12nm NBZ? I have been wondering about this when i live in a heavily lightpolluted area. And yeah for what kind of scope you should use for the videos? The RASA on paper should be better for getting much as possible integration for a youtube video production and you can just BlurX the bloated stars. The Quattro is kicking some serious ass though and the big money RASA should fear for its existance.

[@lukomatico]

Hey mate! Thanks so much for taking the time to weigh in on this, it's appreciated 👍 As to the proposed scenario - the soul test actually wasn't too far off that actually! I should have mentioned the filter in use specifically for that test, - The quattro had a player one anti-halo pro filter, 3.5nm dual band The rasa had an optolong l-extreme f2 edition, 7&8.5nm dual band Hope that helps! Agreed by the way, the RASA is highly useful for getting a target just done with asap - but, the quattro put in such a good showing that it really gets me thinking haha! Clear skies 👍

[@timcorso6337]

Never used a Newtonian, but where are the diffraction spikes on the Quattro in your images? Can you explain please?

[@operator911]

I thought I saw the spikes in the first image he showed… was a giveaway which one was the newtonian

[@lukomatico]

Hey mate! - There are small spikes visible on the brighter stars in the images, but in the regions I imaged there weren't any truly bright stars which usually cause that kind of big bright diffraction spike that you might be expecting! :-) Hope that explains it!

[@ROY-COLLEY]

Hi I know you had a 250pds at one time. Well I just got one too. Is it ok to use a EQ5 ? Your input would be truly welcome.

[@lukomatico]

Hey mate! - sorry about the late reply to your initial comment, I've had a rather busy week so far aha! I'd say while you could technically mount the 250pds on an eq5, it'll be very undermounted so guiding and imaging will be very difficult indeed, expect quite a lot of star trails/wasted exposures etc - sorry to the bearer of bad news! Give it a go though by all means, if your location is quite protected from wind you might be able to get reliable 30s exposures or something :-) Good luck!

[@jimgunn4498]

I have been thinking the same thing lately. I received my new ASI 533MC and am loving the long exposures, however, on my WO GT71, it is quite undersampled at 2.31 arc/sec/pixel. I still have my ASI 183MC Pro, which has a horrible Amp Glow, but the 2.4-micron pixels put it at 1.47 arc/sec/pixel. I just mounted it to my telescope and am now waiting for some clear skies to test it out. Even after drizzling x2, the 533 images don't look as good as the old 183 images. I may have to take 3-5 minute exposures instead of 10, but as my goal is pretty pictures, that is a price I am willing to make. I also just spent a grand upgrading my PC so that I can stack data in hopefully a few hours instead of the 12-16 hours PixInsight is currently taking. Wish me luck.

[@jimgunn4498]

My ideal camera would be a 2.4-micron pixel camera, APS-C sized sensor with zero amp glow and 16bit ADC. Oh, and if they could make it a DUO...Come on ZWO!!!

[@lukomatico]

Hey Jim! - I'd certainly consider keeping the 533 in use but instead maybe look at a longer FL telescope to accompany your gt71 if possible! That'd get you the best shots possible :-) good luck and clear skies!!

[@jimgunn4498]

Yeah, for now, I am cooked. The GT71 is my recent upgrade from a SharpStar 61, plus I ordered $800 worth of brand new Optolong light pollution filters and just this last week or two spent $1200 upgrading my computer to an AMD 16 core 5950x, 64GB or RAM and a new nVidia graphics card because the new CPU doesn't support graphics natively. Then I installed my new CPU only to find out it only supports 8 cores...My initial $600 investment turned into $1200 in a hurry. But, it will now process the crap out of some PixInsight WBPP and xterminators. And isn't that the goal. :) @@lukomatico

[@KalashKat]

Luke, are these cameras cooled? Because I'm seeing a lot of noise here.

[@lukomatico]

They are indeed! the stretch being applied by STF is pretty extreme so isn't representative of how you'd really stretch data, that said, after NoiseXterminator is applied in the comparisons there's very little noise left overall even with such a stretch! :-) Cheers!

[@sdoseri]

How is the guiding with eq6r with high With high focal length

[@lukomatico]

Hey mate! - my eq6 has been a workhorse to be honest, it always guides well but does require a small seasonal adjustment from winter imaging to summer imaging conditions :-)

[@deep_space_dave]

Hey Luke! If you remember, I did a used a small pixel camera on my RASA 8 to get a 0.75 arc second image scale and I had similar results. The only problem was the noise as there are no small pixel cooled cameras under 2.3 microns. The Quattro really blows the RASA 11 out of the water and F4 isn't that much slower than F2 and way less finicky! After your video, this got me really thinking about trying out a newtonian 🙂 That Quattro is a fine instrument for the price! Thanks for doing this comparison as this really shows what BXT and NXT can do when the underlying pixel scale is much tighter. Clear Skies mate!

[@lukomatico]

Hey Dave! I do remember mate yeah :-D I had some good fun doing this, totally agree there's no doubt the Quattro was the clear win when it comes to resolution! It's certainly got me thinking about my next steps anyhow haha Clear skies dude!

[@Rainy78]

Man ohhh man! I want a quattro for my EQM-35i mount. 22lb payoad. Think itll work? The results are astonishing fir the price!

[@lukomatico]

I think it would work in terms of weight yeah, I'd just avoid the quattro as a beginner as I mentioned 👍 Clear skies!

[@Rainy78]

​​@@lukomatico I like a challenge lol I think this would really help me learn and dive into the hobby 🤷‍♂️ Thanks mate! 😁

[@d.fresh.750]

I think I would also go for the finer pixel scale. Great images from both though! Clear skies!

[@lukomatico]

Thanks for taking the time to give your thoughts mate!! - I'm definitely leaning that way myself too really, it's just really nice seeing those extra little details, it excites me more than overall brightness/signal does! :-)

[@ApoorvaIyer]

Hi Luke, great video! Have you considered drizzling both sets of data so that the pixel scales match? That would make the comparison slightly more even between the post blur exterminator output.

[@lukomatico]

Hey mate! It's a great suggestion and something I'd normally do, and maybe should have done for this video yeah! I just thought for the sake of this comparison that leaving the data 'as is' would be useful 👍

[@rowgegaming5048]

From a photography standpoint, this is as much a comparison of the 2 f ratios as it is the telescopes themselves. A telescope with a ratio of f/4 is going to have an advantage in terms of sharpness over a telescope with a ratio of f/2.2 You can see a difference in sharpness just in a regular camera if you take a photo (like of a landscape or something) at a wide aperture like f/1.8 and then stop down to f/5.6 and take the same photo and there's a clear difference in sharpness in favor of the one taken at f/5.6 The trick is getting that longer ratio with a bigger aperture without creating a big wind catcher. I put the OTA from a Apertura AD8 - 1200mm f/5.9 208mm aperture - on an ioptron cem40 and got some nice images when there was no wind despite being crazy un-balanced LOL. I didn't use rings, I hard mounted it using the mounts that are already attached to the tube, so the camera was always sticking up and to the left. Still worked tho haha

[@lukomatico]

Hey mate! :-D There's so many differences between the two rigs (f/ratio being one, as you mention!) that it can't ever be a fair comparison for sure, still fun to do though! 👍👍 Glad to hear you've had some nice success with the AD8 by the way!! That's what it's all about bud :-D Clear skies!

[@Darren_71]

I'd never part with my RASA11 Best scope I've ever owned It can produce full completed images in only 1 night/session, great for the UK weather. It doesn't have flimsy spider vanes so rarely/never needs collimation. The Second best scope I ever owned was a SkyWatcher190MN. Not fast, but zero Collimation needed because it has no spider vanes. I could drive the 190MN to a star party down a bumpy lane in the back of my campervan, throw it on the mount & start imaging.I Did that plenty of times

[@lukomatico]

Hey mate! The RASA's strong points are really quite something aren't they! As you mention, the ability to get an image done fast as heck is a real boon in the UK! I always fancied a MN190 btw, but the right opportunity never arose, great scopes I hear 👍

[@Darren_71]

@@lukomatico if it wasn't for the RASA's speed and UK weather, I'd still have my 190MN. Stunning optics, I'd say it's not far off a Similar aperture Triplet, for a fraction of the price, fairly light and easy to manage/use. "Bugger am I talking myself back into getting a 190MN again 😆" Enjoying your video's, good work 👍

[@maojiexu7435]

The disadvantages of Newtonian telescopes are size, weight and collimation problems. If I rarely moved my telescope, I would definitely choose the Newtonian telescope

[@lukomatico]

All true mate yeah! newts are generally pretty massive haha! :-D

[@MegaMichaeltodd]

I wonder how much of the Rasas problems are due to the fact that it's so fast the stars are getting blown out and not the inherent sharpness of the optics

[@lukomatico]

Hey mate! - Good suggestion! Luckily for this comparison I made sure to use short enough exposures & low enough gain values that nothing apart from the very brightest star cores were burned out, so we can rule it out in this particular comparison! Clear skies mate! :-)

[@keithhanssen7413]

Were these imaged with the same model camera?

[@lukomatico]

Hi Keith! - different cameras mate, I go through the full spec early in the vid if you're interested 👍

[@Z-add]

What's the reason rasa 11 didn't perform as well.

[@lukomatico]

Good question mate, I think various factors were at play - without further experimentation it'd be impossible for me to accurately say what happened though!

[@mikeharden7904]

I thought it was a good comparison. Very interesting. Luke, sell the RASA 🤣!

[@lukomatico]

So glad to hear it Mike! :-) I enjoyed putting it together!!

[@TelfordO]

Quattro 🌌🌠

[@lukomatico]

Thanks mate! :-D

[@frackcenturion]

like what i said f4 up is more friendly 😁👍 cheerz

[@lukomatico]

It certainly is mate haha!! No kidding :-D clear skies bud!

[@grandmasteryoda9893]

the fact you can get a f4 newt at 8inch for 500 buks. tale me: it is not much to prefrormense value in the rassa. nexus can make it f3 than only .8 of in speed. and stil save money.

[@lukomatico]

You get so much for your money with a newt, 100%!! :-)

[@RumourHasitYT]

Your making me regret selling my 10” F4 Carbon Newt 😨

[@lukomatico]

I'm so sorry mate! 😅

[@Steve_The_Ignorant_Astronomer]

Wow nice difference . Luke just one favor , I am not a speed reader ... Scroll a bit slower LOL ... Stay well

[@lukomatico]

Hey mate! :-D Noted! - I did go a bit quick with some of that text didn't I, haha! Sorry about that and clear skies to you matey!

[@Steve_The_Ignorant_Astronomer]

@@lukomatico Luck ,question. I know you have a RASA and wondering if the corrector plate is sealed. Just found out the hard way that my 9.26xlt is not , so heavy dew the inside of scope gets wet , the inside of the corrector plate and even my mirror was fogged over , I never had that with my meade , dont understand why they never sealed and wonder if I can

[@boaty1968]

Quattro from me Luke

[@lukomatico]

I appreciate you giving your thoughts mate, and I agree haha! :-D

[@davidecattani8282]

In your review the Rasa is much more undersampled then the Quattro, thus less details, straight. The RASA needs tinier pixel to exploit its potential, like the ASI294 or ASI183; the ASI2600 is simply the camera for the RASA. So what's you're talking about is not a comparison between the RASA and the QUATTRO, but about the ASI2600 on them. In my opinion this video is quite misleading, which I don't think is you intention.

[@lukomatico]

You may have skipped around the vid a bit and missed me talking about the pixel scale and scope differences, and why this isn't meant to be a fair comparison, but just a fun experiment all the same 👍

[@davidecattani8282]

@@lukomatico yes but people is concluding Quattro is better than RASA, skipping the disclaimers as well. It's simply the wrong conclusion you're communicating, for fun or not. At least, reconsider the title: "Rasa vs Quattro with ASI2600MC". That would be correct

[@lukomatico]

@@davidecattani8282 I, with respect, disagree! There's nothing wrong with my title or video, if people wish to skip and miss out on info that can hardly be put on me :-D

[@davidecattani8282]

Ok, never mind. Just consider people is thinking you're comparing 2 OTAs, while you're comparing two sampling rates, quite clearly though! 😉

[@J.53780]

.

[@timothymaurer6720]

As the creator said, this is hardly a fair comparison but more of an example why it is important to match you camera to your optical system. Here we have nothing more that a comparison of 1.25 arcsec/pixel vs 0.75 arcsec/pixel. Add to that, the advantage of 800mm focal length vs 620mm. I think the "winner" was not a surprise at all.

[@samuelandrew4500]

Disagree, the Rasa wouldn't resolve more detail if you increased the sample rate, it's already hit the limit of what the optics can achive, the spot diagrams are available, it wouldn't support 0.75 as/p.

[@timothymaurer6720]

The only resolution limit achieved by the RASA was due to the pixel size of the camera (and maybe seeing). The Dawes limit of an 11" RASA is under 1/2 arc second. The camera matched to the RASA only 'allowed' a resolution of 1.25 arc seconds per pixel. Like others mentioned, swapping the cameras would be an interesting comparison.

[@samuelandrew4500]

@@timothymaurer6720 The Rasa is no where near diffraction limited, smaller pixels isn't going to make the stars smaller. Happy to be pointed to any photo from a rasa 11 where the fwhm is under 1 a/s

[@timothymaurer6720]

@@samuelandrew4500 shorter exposures make the stars smaller. At f2, RASA stars will bloat in a very short period of time. Sorry but everyone has seen what 11" RASA can do and it is heads and shoulders above an 8" newt. Is the RASA a lot of work to get those results? You bet. Does it have it's weaknesses? You bet. That being said, it is obvious that the newt in this video performed better but you need to ask why. Again, not an apples to apples comparison.

[@samuelandrew4500]

@@timothymaurer6720 I've seen great images from both scopes, I literally own a Quattro 8S and Rasa 8, I know the strengths and weaknesses; if the 11 is head and shoulders above, then I see no evidence of that in the video, even on the signal noise, with a lower sample rate, it doesn't pull ahead. The rasa has a bigger field of view, but the newt will always win on sharpness.

[@AshA-ww8hc]

Geez more distracting background music...

[@lukomatico]

Sorry it bothers you mate, that's not my intent! :-) Hope you have a great day!

[@TheVillageIdiotUk]

Quattro for me - the image looks positively better and finer to my old eyes.

[@lukomatico]

Agreed mate aye! It does look great especially after the usual processing steps are applied, the gap only seems to widen