This BUDGET f4.5 refractor TROUNCES the RedCat 51! SVBony SV555 FULL REVIEW!

[@CuivTheLazyGeek]

20241218: update video on the backfocus situation, kzbin.info/www/bejne/q6XapXyPi9CIe80 20241216: there have been reports on CloudyNights of a samples that couldn't reach focus with the standard 55mm of back focus. I haven't had that issue, but I had inserted a UV/IR cut filter in the scope (and had it in throughout testing), which does shorten the backfocus. I have contacted SVBony about this. My Patreon: www.patreon.com/cuivlazygeek My Merch Store: cuiv.myspreadshop.com/ For any affiliate link purchases, make sure to accept cookies if prompted! Also, browser plugin "Honey" may steal commissions from creators if you interact with it (even just clicking on "OK" to the "No coupons found" message)! Get the SVBony SV555: bit.ly/3UWR0Os (use coupon Cuiv20 for a further discount) Alternative, Askar SQA55: bit.ly/4hEfW7l (Agena) or bit.ly/48u4PJC (HPS) or tinyurl.com/24mek4vc (FLO) or tinyurl.com/5yw5ccrd (All Star Telescope) Universal Focus Mask: tinyurl.com/p97bb3ub Cameras used for testing: ZWO ASI2600MC Air smart camera: tinyurl.com/tr2r3esn (ZWO) or bit.ly/3SV04Co (Agena,) or bit.ly/3SZARXx (HPS) Touptek SkyEye 24AC: tinyurl.com/yjwd836e Amazon affiliate: amzn.to/49XTx01 Agena affiliate: bit.ly/3Om0hNG High Point Scientific affiliate: bit.ly/3lReu8R First Light Optics affiliate: tinyurl.com/yxd2jkr2 All-Star Telescope affiliate: bit.ly/3SCgVbV Astroshop eu Affiliate: tinyurl.com/2vafkax8

[@lukomatico]

What a superb review mate, once again you raise the bar - It's clear how much work you put into these videos! - The performance is extremely promising at that price point, just unreal! R.I.P RedCat 51 I guess, lol! (Thank you so much for the focus mask shoutout by the way! That was unexpected but really cool :-D)

[@Chiclets1]

But the red cat is so purdy 🐈 . Lol. I'm a dog person myself. 😅

[@CuivTheLazyGeek]

Thanks Luke! And your focus mask is so convenient, I use it all the time!

[@TheBananaPlug]

Just finished a first light with an SV555 bought based on this video (used your coupon - Thanks). All good, as reviewed, very happy with my purchase. Camera used was a ZWO ASI1533 MCPRO.

[@CuivTheLazyGeek]

Woohoo! That's awesome!! Hope you can enjoy more clear skies!

[@theamateur8562]

Where’s the video!!!

[@iamjessieray]

Svbony is seriously becoming the budget king of astronomy and astrophotography. I have a few of their accessories and a couple of their cameras and the only thing I must say is that ZWO's version of a camera with an IMX585 sensor has a larger RAM cache and so is better for planetary work, but other than that I am very happy with all of their products I have used so far. I had been looking at maybe getting one of Askar's lenses/telescopes of the same design, but that was before I knew this existed! I would also love to see them come out with some newtonians, but they seem really focused on cameras and refractors at the moment. I guess that is just what most of the astrophotography community wants right now. Speaking of, have you had a look at any of their ED doublets or their Maksutovs?

[@BenGieCruz]

At $519 with free shipping using your disc code this is a no brainer! Might have to pull the trigger now! Excellent review brother!

[@DeepSpaceAstro]

That's pretty cool they give you what you need for the EAF!

[@CuivTheLazyGeek]

Yes it's nice not to have to buy it separately!

[@ArturMunz]

Hello Cuiv! Thanks for the great test (as always)! In distant Germany I have been waiting for your test. Immediately, after watching your recession twice, ordered with coupon. Thanks again for your great and entertaining contributions. Artur

[@CuivTheLazyGeek]

Congrats, I hope your sample is every bit as good as mine!

[@andrewweller5119]

saved me! i was just about to go with the Redcat but now I have seen this I will definitely be looking into it further before I buy.

[@CuivTheLazyGeek]

Consider the SQA55 too!

[@JackKolesar]

Have been waiting on a review of this scope. Incredible! Ordered with your code. Thanks!

[@StuartAnderton]

Got first light on mine this evening. Glad to say focus achieved with no issues. Phew.

[@CuivTheLazyGeek]

That's awesome news!!! Thanks for the update! How are the star shapes?

[@StuartAnderton]

@ Seem OK to me. ASIair reporting average size 1.9-2.1. But 98% Moon and shooting through gaps in clouds so not ideal conditions.

[@StuartAnderton]

Had my first proper session with mine on Sunday - wow, this thing is amazing. Not just for the price, just brilliant full stop . Don’t be put off by the focus gremlins folks, catch this in the AliExpress sales.

[@woody5109]

Great review, nice to see affordable options because it’s easy to review high end gear. Also, great music.

[@CuivTheLazyGeek]

Thank you!!

[@dawgmach1913]

Cuiv - As usual, great review. As a follow up to your review of the WO Redcat 51 Mini, I can confirm sizable egg shaped stars on the edges using a APS-C (ASI2600Air) camera. I skipped trying a full frame camera based on the marginal performance of the scope using APS-C sized sensor. Keep up the good work. Thanks!

[@CuivTheLazyGeek]

So the RC51 Mini seems to conform to its warning and spot diagram! Good to know, and it's still a fun little F3.5 scope!

[@DrawsACircle]

It just entered my Christmas/birthday wish list 👍😊

[@joeshmoe7967]

I got my first telescope (Celestron C-8) in 1978, still have it and use it. Didn't really get into astrophotography until 2018. Since that time there has been an explosion of gear, much of it focused on the budget hobbyist. This scope here just adds to that, and seems like a fantastic scope for the money. Star shapes definitely good enough for me.Them thinking forward to auto focus is something you wouldn't think would be at the price point. I am looking for more aperture and focal length but SBvony definitely on my list, for future pieces of gear. Great review.

[@CuivTheLazyGeek]

Yep, I was really happy to see the EAF kit in the box (minus the EAF of course!). You know maybe the SQA85 or 106 from Askar could be what you're looking for!

[@clearmore3024]

Had pretty much decided on the Redcat 51 until seeing this. I don’t mind spending extra for the SQA55, so I'll wait for your review on that. Very helpful, thanks.

[@CapWebInformatique]

Superb video! I have been using the Askar ALC200 with focuser and an ASI6200MC for almost three years... the result is impressive, this other SV555 lens is I think identical with a better package and a much lower price...

[@MrMaunotube]

Thanks for this Cuiv, I as waiting for such review on this lens. It looks to be a very good cost x benefit option for large DSO astrophoto.

[@CuivTheLazyGeek]

Yep, exactly!

[@DanielMercado-d5y]

Thanks for this review, it's amazing. I would like a review that compares a takahashi telescope (babyQ 85 or Fsq106ED) with some equivalent telescope and that way see if the extra money is really worth it or not. THANK YOU AGAIN..

[@CuivTheLazyGeek]

I would love to get my hands on either the BabyQ or the FSQ106, but I don't think Tak is much into KZbinrs doing reviews! Would be a great comparison to make! Deep Sky Geek has a BabyQ, so maybe he can compare down the line!

[@xj650t]

As an apprentice lazy geek, I'm always conflicted with a review like this. Go and buy the SV555 and be done, you'll get great shots and have to do virtually no setup. Instead for about the same new or even less used, buy a Quattro150, spend hours flocking, changing spider ring, changing the focuser, collimating and you will eventually get better photos. But is it worth all the hassle to do all of that? Another enthusiastic review, thanks.

[@terrizittritsch745]

Nice review but it would be better if you were to blind purchase the lens from a distributor and test it out. I'm always a bit skeptical of optics provided by the manufacturer as there always seems to be some luck of the draw when it comes to economy optics and the likelihood of them cherry picking a copy to send for review.

[@CuivTheLazyGeek]

That's very true! What I like about SVBony is that whenever I ask to review something, they usually send it within hours and from a warehouse in Japan/Osaka... So if they're cherry picking, it means that they have a cherry picked stock always ready here 😅 That said for this SV555 as it is very new they didn't have stock in Japan yet so they did send it from China. Of course SVBony has told me multiple times they do not cherry pick... What makes me a bit more comfortable with this though: - SVBony stuff I bought myself (such as the SV220) were pretty close to specs - SVBony stuff I received from them were pretty close to specs but not perfect (I would expect cherry picked stuff to be perfect, although this could be 4D chess) - my experience with the Askar SQA55 tells me that such budget optics now seem to be actually possible with reliability (for that scope I was able to get feedback from others on multiple samples, all were excellent)... Still, I agree this is a possibility!

[@terrizittritsch745]

@@CuivTheLazyGeek Thanks for the response. I don't have experience with the newer manufacturers and if they've truly gotten to a consistently higher level of quality that's great for everyone. I wonder how this affects the premium optics makers? It doesn't seem to affect pricing yet (smile).

[@chridignan9178]

Great vid, thank you. I'd also strongly steer folks to look at the Askar FMA 180 Pro F4.5 Astrograph (Sextuplet) with no flattener needed. Price is way lower at £GB 374 and has a similar extra focuser rig for the EAF. I'm having brilliant results with it!

[@CuivTheLazyGeek]

That one has great feedback as well, gets into the extremely wide field though!

[@shadowOrgon]

so glad to hear that! picked one up recently to be part of my first rig, hoping I can get it all to work out when I get the rest of it ordered.

[@ColeDedhand]

3:17 Svbony needs to make a replacement backplate to shorten the back focus a couple of millimeters. Then send that replacement to everyone who bought one.

[@CuivTheLazyGeek]

Sounds like another possibility!

[@texasman2907]

Big fan of your videos especially those like this one. Been on the fence and this pushed me over. Thanks for the coupon code--more money to buy something else!

[@maurodoria1665]

Thanks for reviewing svbony sv555!

[@CuivTheLazyGeek]

My pleasure!

[@imspartacvs]

Great stuff as always. Way over my head but I still listen and get a little bit of knowledge every time. Matt Hudson Valley NY

[@CuivTheLazyGeek]

Glad you enjoyed it, Matt!

[@Phillyo118]

Great review, I'm interested in the SQA85 or maybe even the 106. Also love your little Contact reference. Small moves Ellie. Such a great movie!

[@CuivTheLazyGeek]

Glad you noticed the reference! :D I love that movie, still rewatch it regularly haha. Also I'd love to get my hands on a 106!

[@Phillyo118]

@CuivTheLazyGeek I'm going to watch it again soon now, so good haha. I'd be very happy to watch a review of the 106!! Especially if you can try your full frame camera with it. Thanks for all the videos, very useful and a great to watch. Appreciate it.

[@anjagrell3794]

Hey there Cuiv, thanks so much for the video, and... it's all your fault 😂😂😂 No, seriously, your review came at just the right moment. And Svbony is on my radar, because they build good quality for a more budgeted market. I already own a few parts of equipment from them and I am satisfied. So, thanks again to encourage me to the next piece e of equipment. Turns out, I am on my way to make a copy of my S50 😊 It is so amazing, how much one can learn while watching insightful videos from enthusiasts like you. Not just your reviews, but your tutorials too 👍🤩 Happy Holiday season and CS 🔭🎅

[@standfest_party]

It looks impressive! If I didn’t already have the Askar 65PHQ with a 0.75x reducer, which gives me 312mm at f/4.8, I would definitely buy the SV555!

[@mireianievasrosillo8021]

Btw, thanks for the video with the touptek OAG + filter drawer combo. Got myself a kit of OAG-X + filter drawer + GPM462 + touptek 2600c in the current sales. Pretty sweet deal wellllllll under 2k.

[@ralfdinkelmeyer6221]

Cuive! Very impressive, just ordered using your link!

[@CuivTheLazyGeek]

Hope it works out well for you!

[@TheOriginalTommo]

Looking forward to the SQA review. Some stunning sample images on Astrobin 😆

[@physmc1]

Nice review. Looks like another great option for wide field. Looking forward to your review on the SQA series as well. I’ve got a SQA85 still waiting for first light . Looks like a winner based on spot diagrams

[@CuivTheLazyGeek]

Oooh I'm looking forward to your feedback on the SQA85!

[@physmc1]

@@CuivTheLazyGeek Sure thing. Though I need a clear night for that first, which is easier said than done in the current Pacific Northwest weather :)

[@edjones3390]

I will need a travel scope in a few months, this is now near the top of my list, cool that they include the EAF mounting kit 👍

[@ferenc-x7p]

Consider it, because the alternative is something that costs $60-$100 more with all the other scopes I have looked up so far.

[@CuivTheLazyGeek]

Yep, nice to see there isn't an additional purchase needed!

[@junweisun7198]

For the spikes, you can try move your lens ring to another position or not screw the ring too tight, to remove the residual stress. Maybe it is introduced by the pressure to the lens.

[@craigperkins9845]

Ive pre ordered one. Waiting patiently for delivery.

[@CuivTheLazyGeek]

Hope you enjoy it!

[@KingLoopie1]

Impressive for the money! As always... Nice final pic! 👍👍

[@CuivTheLazyGeek]

Glad you liked it!

[@marcusa3177]

I wonder if 1) you can put the EAF on that mount point to the side of the ring 2) the timing belt will still fit. If yes, you'd end up with a rig with a lower center of gravity (good for smaller, lower-capacity mounts). Use the handle for the miniPC/ASIAir, then position an OAG* so it's sticking out to the left (ie to serve as a counterbalance for the EAF), and you'd have a really compact setup * yes overkill for this focal length but if you have multiple OTAs, OAG is the way. The camera, EFW, and OAG basically lives as a unit, and you just swap out the OTA depending on the target.

[@JanLauritzen]

Hi, great review. On a different matter: could you perhaps make a video regarding the difference physics between green and blue ar-coatings on lenses? Perhaps an insight into the aspects of these coatings with regards to wavelenght transmission and reflectivity and other things that might be relevant for this topic?

[@MrsBMusic]

Wish this had been posted last week - I just got a RedCat in the mail yesterday as I was nervous to purchase this without any reviews out there.

[@CuivTheLazyGeek]

Well, the RedCat is still a very good scope!! And I do think its WIFD focuser is better than helical focusers, so enjoy it for now!

[@shinyy187]

I’ve had my Cat 51 for a year and a half now and use with the 533mc pro. I’ve never seen any bad stars with it. But the 533 is a cropped sensor so I can’t say anything about full frame.

[@SvenHild]

Wow I think I asked for the Review only 2 weeks ago. Thats fast!

[@CuivTheLazyGeek]

Yep, SVBony were also fast to react!

[@deep_space_dave]

SVBony really upping their game for affordable quality!

[@CuivTheLazyGeek]

Yes!!!

[@Astro_Shed]

Nice one Cuiv, I have this scope on the way for review also, very king of SVbony to send it out..CS 👍🏻

[@CuivTheLazyGeek]

Awesome! I hope it works out great for you as well!

[@DeepSkyChronicles-m8b]

I knew they will send you a copy for review :-) . Thank you very much for this great review.

[@CuivTheLazyGeek]

Yep, they did! It's an awesome scope.

[@sjpp71]

Holy round stars, Batman! That's impressive! And no visible colour separation (tiny bit at the edge). The lens in the doesn't outside looks too stylish (russian, as you said), looks cheap, like one knock off, lol. But the results speak for themselves. Definitely, at least your sample, blows the RC51 out of the water. I will keep an eye on this one, let's see how it goes, if no issues start to arise, and if people is overall happy with it in the medium/long term term. Clear skies (from Brisbane, Au, engulfed by clouds...)

[@CuivTheLazyGeek]

Yep, seeing results from others will be important!

[@ColeDedhand]

I like the look. Doesn't look cheap to me. Looks rugged. Retro.

[@sjpp71]

@@ColeDedhand yes, more accurate description

[@efx245precor3]

It’s got to be better than MiniCat51 corners. Petzval yes! Though I see spacers in the setup.

[@AstroJWA]

Cuiv, You have been my inspiration for astrophotography. I was watching one of your older videos where you mentioned that the ZWO EAF was garbage. Do you still feel that way? If not, what changed? Thanks for all your content. I watch all of your videos.

[@CuivTheLazyGeek]

There used to be huge amounts of backlash on some units, with variable unit quality! It's better now (basically since the USB-only versions), and also software has gotten better at handling fixed backlash!

[@dalehollenbaugh6084]

Good review Cuiv, but I think your RedCat51 is a poor example. I suggest you contact William Optics to see if they can refigure the optics because that is subpar and not doing justice to what it is capable of. Considering your notoriety and platform, I would think William Optics would be more than HAPPY to fix or replace your RC51. My RC51 appears to perform significantly better than your copy. The SV555 is an impressive value, but I see more chromatic aberration with it than my RC51, although I think the stars are slightly more round and tighter on the SV555, at least out to APS-C, which is what I use. I can't wait to see your review of the SQA55, because I think it will really trounce the RC51. One note about cost. The RedCat51 does actually have Ohara FPL-53 SD glass, which we know is more expensive. The SV555 uses ED glass, so not as good (and CA is apparent) and the SQA55 does state that is uses one ED and one SD element (presumably Hoya FCD-100), so should have superior CA performance to SV555. Nowadays, FCD-100 seems more popular than FPL-53 with about same performance for lower cost.

[@CuivTheLazyGeek]

I got mine second hand, and since I'm now in the process of purchasing the SQA55 I reviewed I think I'll be selling it! That said, even if my sample was perfect, the spot diagrams do show limitations - still, this is good to know!!

[@probro4914]

Ordered one because of you. I liked the EAF setup better than the SQA55's, even though I'm predisposed to prefer Askar (I own a ZWO FF80/80PHQ). Much more compact with the EAF between the rail and scope rather than sticking out the side with a more complex pully system. A couple questions, if you don't mind: Did you have to use a 54mm-to-48mm adapter to get the M54-16.5mm spacer to screw onto the lens? Does the EAF belt match the grooves on the focus ring? Thanks!

[@CuivTheLazyGeek]

Congrats, hope you'll like it! I personally much prefer the Askar design as it doesn't move the whole scope away from the axis of rotation, increasing the moment arm and the moment of inertia :) Can be very important for people using mounts like the SW GTi! Otherwise yes, I had to use a 54mm to 48mm adapter (which came with the camera) and the EAF belt perfectly matches the grooves on the scope focuser!

[@probro4914]

@@CuivTheLazyGeek Thanks for the reply! Interesting thoughts on using these on marginal mounts. I doubt my AM5 will care though. ;)

[@ColeDedhand]

Ordered the bundle using your code. 700 for the scope ,filter drawer, dual band filter, 30mm guide scope.

[@CuivTheLazyGeek]

That's a great combo, you're going to love it!

[@stanmacdonald1073]

That is another excellent review. I do notice that there is more vignetting at the bottom than the tops of the image. How much more loss is there at the bottoms than the tops? Or is that Tokyo light pollution? Thank you again for an excellent review.

[@CuivTheLazyGeek]

Thank you! I'm not completely sure - it is exaggerated by the stretch, maybe next time I should also show the flat frames!

[@fn3048]

This is the FIRST EVER influencer video I have actually taken notice of and purchased :) I just wish SVBony would add AfterPay option to their webstore, so sorry, instead I bought it on SVBony eBay with their Black Friday 20% off coupon. Smaller upfront payment keeps the Chief Financial Officer of Home Affairs (aka WIFE) happier :) I bought the bundle offer with the 2" duoband filter, 30mm guidescope, filter drawer and finder shoe (no dew heater, but I have spares) for the same price as the bundle on the official site. I have been an SVBony aficionado for a while - have their EXCELLENT SV550 80mm triplet and couldn't be happier. Every bit as good as the Takahashi's I've owned for the past 20 years. Only thing I ever change on the SVBony offerings is their thumbscrews - I have other preferences.

[@CuivTheLazyGeek]

That's awesome to hear!! I hope your sample will be as good as mine!

[@waynewheaton3210]

Does Cuiv sleep? He's been banging out these great videos lately. So many telescopes, so little time and money.

[@CuivTheLazyGeek]

I try to sleep 😂

[@dmperreau88]

5:41 - Curious, how many mm of spacers were used? Didn’t look like it was 55mm but I might be wrong.

[@CuivTheLazyGeek]

It was the standard adapters that come with the Duo/Air: 21mm+16.5mm, and the camera back focus of 17.5mm - and of course I had a filter within the scope that shortens the light path

[@msacco]

Sorry, but this is just MADNESS. Can't believe you can get such crazy quality for that price point, I have no words, WOW.

[@CuivTheLazyGeek]

Right?! I'm loving this!

[@EvenTheDogAgrees]

To me the stars looked elongated across the field. But all in the same direction, no matter which corner you look at. Which leads me to believe the optics are capable of more, but this stack was held back by imperfect tracking performance.

[@CuivTheLazyGeek]

Huh, I don't see it to be honest - you're watching in 1440p? Guide RMS was something like 0.6"

[@drunk_astronomy]

great review!

[@CuivTheLazyGeek]

Thanks!

[@kevinhutchinson8129]

Great review Cuiv. You've wet my appetite! I ordered this lens over 1-1/2 months ago for SVBONY (along with their 7nm UV-IR cut filter) and am still waiting for it to show up on my doorstep (supposedly it cleared customs yesterday. Yeah!). I also purchased a ASI2600MC Pro to use with it, so seeing your images using that camera make me think I didn't make the wrong choice. You've left me thinking this will be a fantastic "grab and go" astrograph! I do have 2 questions, if you don't mind: What spacers did you use to achieve 55mm of back spacing and which UV-IR filter did you use? Thanks!

[@CuivTheLazyGeek]

Woohoo it's almost there! I hope your sample will be every bit as good as mine! For the 55mm of backfocus, I just used the spacers that came with the 2600MC Air camera, and I fit in the SVBony UV/IR cut filter in the scope (and thanks for reminding me, I still have it in there, I need to remove it before I send it back!!)

[@FranklinNewhart]

How about a comparison revue of this compared with an Askar 135mm f4.5 APO Astro Camera Lens - FMA135. The SVBony 555 goes for $805.00 Canadian where the Asker goes for $413.00 Canadian

[@astroworldcreations2047]

Thanks for this excellent review Quiv! When you compared spot sizes, did you compensate for the fact that the scales are different for the Askar (200 micron) vs svbony (100 micron)?

[@CuivTheLazyGeek]

Yes! I called it out in the video too :)

[@photoworldcreations8753]

Great, sorry, must have missed that.

[@namorandy]

Great review Cuiv, only missing how to look like with Dslr

[@CuivTheLazyGeek]

I don't have a DSLR so I can't show that, but it's just a standard M48 T-ring!

[@kowalskik.1333]

Could you also check even smaller more widefield scopes? The big question for example is always ASKAR FMA180Pro or FMA230 or ALC200 or FMA135.. Hard to decide here between this three. Never know which one has the best star shape in the corners and the least chromatic abberations.. Just an idea for a video.. KR

[@jimenoroylandm.4855]

does gemini EAF can be fit in this telescope?

[@stewartdavis8618]

Hi loving your videos, very refreshing. I'm just planning my observatory, and wondered what Refractor you would recommend between $2000-2500 ? I will be using a ASI 533MC Pro.

[@KevinRudd-w8s]

The only reason I wouldn't buy one is I already have a Red Cat 51 and a Samyang f2 135. But I can see why you would choose this over the Red Cat. For the price of the cat you could buy the SV Bony and an EAF and maybe have some money left over. Good review anway Cuiv. Just asking, did you use Blur X or Seti Cosmic Clarity on the Red Cat image of Andromeda? I found when I used CC on mine, the stars were improved. I think the small refractor market is a bit saturated but, who can complain when someone brings out a good product at an affordable price. Clear Skies.

[@ferenc-x7p]

Actually, the Samyang 135 and the FMA180 (also the FMA235) have been my check marked scopes that I've been planning to buy for months, but just couldn't decide which one. But since you already have this focal length covered, this scope may not give you anything new to work with. For me I just bought it, because I don't have anything under 450mm fl.

[@sjpp71]

@@ferenc-x7p I'm also "trapped" in wide field, lol, with my fma180+294mm and evoguide+Starizona FF (260mm fl), and got one edph50 in the mail (to replace the evoguide). I haven't used my longer scopes in a while!

[@CuivTheLazyGeek]

You need a 107mm aperture refractor or a Newtonian now haha No BXT on the Andromeda image, that was before I had BXT :)

[@wooddogg8]

Interesting, seriously thinking of a new telescope Maybe I should just wait and see what happens, just wait and see!

[@BenGieCruz]

Have you tried fixing a vixen dovetail plate on the side of the ring where those 4 holes are? If it fits we might be able to attach an asiair right there!

[@OVSoftLLC]

Thank you, Cuiv, for a really useful review. Can this refractor be used with an OAG?

[@CuivTheLazyGeek]

Yes - I was effectively using it with an OAG by testing it with the 2600MC Air

[@OVSoftLLC]

Thank you for the answer. But what is about more standard OAG with 2 cameras?

[@CuivTheLazyGeek]

@OVSoftLLC sure, no reason why it wouldn't work, it's like any other telescope and it has the back focus to support it!

[@Sk240DC]

Excellent review and super educational as always. Question on the spot diagram, according to WO's website, the Redcat 51 has a rms of 3 microns but Cuiv is saying it's closer to 9, am I reading something wrong? Also, the diagram on the Svbony website does not specify a rms but I'm guessing Cuiv is eyeballing the info from the diagram?

[@CuivTheLazyGeek]

Yeah, I unfortunately have to eyeball it - the spot diagram of the RC seems to imply a fairly large spot regardless of RMS...

[@stuartriley4976]

I can't find the number of blades in the diaphragm, but it looks like a lot, which is good. But, no matter how wide it is, the diaphragm will cause the spiking you see in your images. The spiking appears to be minimal for a scope/lens at this price point.

[@CuivTheLazyGeek]

Yep, I guess the diaphragm is still in the light path even wide open, I suspect an aperture mask would actually help, I need to test that!

[@genie4tube]

Great review. What do you think about SHARPSTAR 50EDPH and his reducer and aps-c flat field?

[@CuivTheLazyGeek]

I would need to test it! Another commenter said they got it, but the reducer was defective...

[@rainerscholz2410]

⁠​⁠@@CuivTheLazyGeek Great as always!! Could you put it in realation/rank it to the 61EDPH? Best season greetings from alway cloudy Germany👋🏻

[@JVRost]

Сuiv, hi. Has Touptek offered you a new 585 series monocamera to test yet? It would be interesting, agree. I recently bought myself a SharpStar 50 EDPH on Black Friday, and had no luck, the reducer turned out to be defective, they sent a second copy - I'm waiting.

[@CuivTheLazyGeek]

Not yet! But QHY has approached me about theirs! Too bad on the SS50 EDPH... That's disappointing... Hope you get the new reducer soon!

[@koomber777]

Very strong Tair 3 vibes right enough.

[@CuivTheLazyGeek]

Yeesssss! It's exactly those vibes!

[@eplumer]

when you review the sqa55 compared to the svbony, please tell us about the relative mechanical stability of their mounting systems (ring vs foot).

[@RudolfNovak]

hi, I have aps-h cameras (atik16200 color, g3-16200 mono) on redcat 51 but I never saw ,,comets'' on my images. and less spikes on bright stars that you have. not telling this scope is worse but maybe the comparison is affected by your piece of redcat (some tension in tube maybe)... anyway thanks for introducing me this cheap scope. looks nice!

[@CuivTheLazyGeek]

Good to know!! Although it would mean that the RC51 optics are better than its own spot diagram? The spot diagram itself predicts elongated stars and that's supposed to be the best theoretical performance.... I'm wondering if the large pixels hide the issue (my worry with the FF camera I use for the FF test)

[@RudolfNovak]

@@CuivTheLazyGeek yes I have big pixels and it is like 4 or 5 " per pixel with rc51 (huge I know) and it may cover it for me. I may test it and will with some CMOS with small pixels (QHY268M) and it may appear. But with those aps-h ccd cameras field is flat and very nice... I love that scope for complete lack of back focus issues I'm fighting all the time with flatteners a coma correctors. redcat was easiest to start imaging with. so use large pixel CCD if you need to hide abberation :) keep up good work. I love your videos!

[@jmoreno6094]

Please review the HAC125 of sw

[@CuivTheLazyGeek]

Damon just did a review of it!

[@malek2900]

Finally, william optics prices are ridiculous .

[@CuivTheLazyGeek]

It's good to see competition!

[@robb7342]

Thanks so much for doing this review as I've been looking for a cost effective sollution with this approximate FOV. In the example stars that you show, was this achieved with manual or EAF focusing?

[@CuivTheLazyGeek]

This was with manual focusing (Bahtinov mask assisted)

[@michaelnixon6672]

I have looked at this one. Can you tell me how to add a Barlow to the OTA to double the F/l?

[@efx245precor3]

15:02 might be some pinched optics. 17:30. Some gradients

[@StuartAnderton]

Some on FB and Cloudy Nights reporting difficulties getting back focus correct - has anyone seen that? Mine is on its way...

[@CuivTheLazyGeek]

I'll add this to description and pinned comment - I've also notified SVBony about this

[@StarlancerAstro]

Is this a petzval lens? as in do we need a specific back focus or not?

[@kevinscully6647]

How well does this lens work with a M43 sensor?

[@rawhead909]

How would you compare this with the Askar V @ 60mm and reducer (270mm F4.5)?

[@CuivTheLazyGeek]

The Askar V @60mm is very good, but not as good as either this lens, or the Askar SQA55.

[@rawhead909]

@@CuivTheLazyGeek Darnit!!! Now I have to think about getting this.... LOL Thanks!

[@LukeKwan78]

I went to svbony website and saw you can buy this is multiple ways. just the refractor , cmos camera , and dlsr. what would I lose if I used my sony a1 $6500 body vs a cmos dedicated astro camera? I wouldn't be able to shoot in Fits but ny sony 50mp camera shoots in RAW. what else do I need to know. my sister says my camera will most likely have IR filter so that will be a limiting factor on what I can photograph.

[@EvenTheDogAgrees]

The astro camera might be slightly better, but most of the benefits come from what you can automate with the computer you got hooked up to it. E.g. dithering the mount between shots, assisted focus, ... I shoot with a simple ASP-C mirrorless (Canon EOS-M), have both stock and astromodded bodies. Plenty of targets for my unmodified cameras. Lots of targets don't really emit much, if anything in the IR. The Orion Nebula, M42, is a great beginner example even for us DSLR/mirrorless shooters. Same with Andromeda galaxy (M31) and Pleiades shown in this video.

[@kjellsteel]

Very interesting lense, BTW can you test the Tamron 150x600 f5.6 lense? I use that with a 585 sometimes 👍😊

[@DoronTshuva770]

you said you didn't check but I think you said you got the gemini EAF, could you check and see if it fits? it looks the same size

[@CuivTheLazyGeek]

The Gemini is too "fat" :(

[@DoronTshuva770]

@ o no…

[@actudoran]

nivce lens! top review!

[@CuivTheLazyGeek]

Thanks! 👍

[@OutriderFIN]

I almost ordered a refurbished Redcat 51 already. This looks really good for the price. Is there a tilt adjustment on this scope?

[@CuivTheLazyGeek]

No tilt adjustment on the scope, no! So that's a RedCat advantage right there!

[@mireianievasrosillo8021]

If they make a 90-120mm with this correction, I am in :)

[@StuartAnderton]

Be good to find out id other focusers fit, as the ZWO costs nearly as much as the scope!

[@larryalbrecht5]

I can confirm that the Gemini Focuser does not fit. That was the 1st thing I tried when I got my lens a few days ago... The Gemini is "too fat"

[@Bigalinjapan]

Where do you buy your stuff? To me it appears that offers / brands are quite limited in Japan...

[@CuivTheLazyGeek]

Kyoei, Shmitto, others - quite a few options imo!

[@ApoorvaIyer]

Cuiv just leaked the fact that there’s an upcoming SQA55 review ;)

[@CuivTheLazyGeek]

Spoiler alert!

[@enriqueboeneker]

Hola, Cuiv. I noticed a bit of pinched optics on Deneb, or am I mistaken?

[@CuivTheLazyGeek]

Looks like star spikes to me, I suspect the aperture diaphragm doesn't get fully out of the way even at F4.5

[@luv2flydrones275]

I have a question that doesn't pertain to this video but I'm really searching for a definitive answer before I waste a bunch of money. I use the sv503 102mm scope from svbony. Right now I'm using the asi585 camera from zwo. I want to upgrade to the asi2600mc pro. Other than the extremely large file size am I going to be running into a problem with the sensor being so large for that scope?

[@keithhanssen7413]

Your field of view will be much larger

[@luv2flydrones275]

@keithhanssen7413 I understand but is it "too large" to get good photos between 400mm and 700mm focal length with my 2 refractors? I'm afraid too many targets are going to be way too small for the field of view resulting in less quality. Would I be better off with the ASI 533 MC Pro

[@CuivTheLazyGeek]

I'm not familiar with that particular telescope, so I don't know how well it would work with APS-C size sensors... What would would get is indeed a larger FOV (you can still crop), larger file size, and a larger pixel scale (unable to get as much details as with the 585). So you need to ask yourself: why do you want to upgrade? Do you need that larger FOV at the cost of pixel scale?

[@Ohgodmail]

Very nice 👍

[@CuivTheLazyGeek]

Thanks!

[@deltacx1059]

I wouldn't call it a budget option, it's firmly a mid range option. If you are only looking for a telescope that is a tiny refractor under f/5 then it seems like a good option. But why not get a similarly priced Newtonian? You can have much bigger aperture and good image quality.

[@brainandforce]

Is this usable visually or is it really just a photographic setup?

[@CuivTheLazyGeek]

It is made for photography, I don't think it can be used visually, a diagonal would add too much back focus

[@brainandforce]

@CuivTheLazyGeek I have seen a few small refractors of various kinds (guidescopes too) which have conflicting descriptions and reviews for visual usability...

[@DeepSkyChronicles-m8b]

Just one question, is there any way to reduce or correct the spikes on the big stars ? I have an SV503 80ED and have the same issue. Thanks in advance !

[@CuivTheLazyGeek]

Interesting that you see the same thing on another SVBony scope! I think a 3D printed aperture mask to make it F4.6 could work!

[@ankarstew]

Cuiv, can you please tell me which filter you used for M45?

[@CuivTheLazyGeek]

I had the SVBony UV/IR cut filter installed within the lens (although not strictly needed since the camera has a IR cut window)

[@ankarstew]

@CuivTheLazyGeek Wow, that's quite a lot of detail for very little exposure time and Bortle 8/9! I just took about 7hrs of M45, with the Antlia Quadband (z81 + ASI533) and my final image was not much better than yours. Any thoughts?🤔