William Optics SpaceCat Review

The William Optics SpaceCat / RedCat 51 is a 250mm f/4.9 telescope that pairs great with a SkyGuider Pro or Star Adventurer. The telescope is lightweight, portable, and has great optics. In this video review I'll break down the most important aspects of the Space Cat and let you know if it's worth the investment.
If you're interested in buying the RedCat or SpaceCat:
agenaastro.com/telescopes/sho...
You can also read my full-length review on my website:
www.peterzelinka.com/blog/201...

[@PeterZelinka]

For more information on the Space Cat, including EXIF data on my photos, check out my written review: www.peterzelinka.com/blog/2019/11/william-optics-space-cat-review

[@elizabethmacharia9786]

Guys check out his webpage it has more written detail. After reading do what I did, send an email to Zwo asking them to send a ZWO ASI 1600 to Peter for a review when used on a Space Cat. hahaha

[@v.4.vanquishl177]

Hi there Peter. Just i wanna ask what is the big different between telescope like this one and telephoto lens like 100 to 400 mm lens for astrophotography. Thanks in advance.

[@PeterZelinka]

@@v.4.vanquishl177 In terms of image quality, surprisingly not much. Most 100-400mm lenses I've seen perform quite well at night. Plus, you can zoom in and out to change the composition and make finding objects easier. The main advantages of the Space Cat are the price, included Bahtinov Mask, (optional) guide scope bracket, and the overall size and weight. I used a telephoto lens for the past few years though and was still able to get great photos.

[@hughmongus1233]

In 9 years or less, it'll just become a Dead Cat.

[@Ryan-mw3wf]

Peter Zelinka what tripod did you use

[@rinceart]

This is the best, most objective review of this piece of hardware I've seen so far. It paints a much more nuanced picture of the Space/Red Cat. Thank you so much.

[@jasonmaher4843]

Articulate and informative without an incessant sales pitch. Great video.

[@camsmith5477]

I have heard lots talking about the Red/space cat on forums but this is the best review I have seen. I purchased a dobsonian initially and will keep it for the grandkids to use and marvel at the sky but I think now I will be buying a space cat and a star adventurer kit. Purely because of the portability and the great results it gives..Thanks for a great review.

[@LarryParamedic1]

I am new "Very New" to astrophotography. Your video was very helpful, so far I am just shooting single exposure images with my DSLR. As I learn to stack images along with adding a tracker, a SpaceCat will a welcomed lens to my equipment. Thank You Very Much. Larry F.

[@nelsonrivera6575]

Omg ,this changes everything ( game changer) I was researching to buy a Celestron HD 1" , BUT then you show me this , and now I'm really torn , I'm going to check your other videos on this , your explanation is great , I am a total noobie to astrophotography ,although I been observing for some years ,thanks again, warm hugs from Puerto Rico

[@alejandro_mery]

thanks a lot Peter, I really love your honest and practical reviews

[@monsyschuller3561]

Hey Peter, as always a pleasure to watch! Greetings from Germany!

[@IcedReaver]

Great in depth review, thanks Peter. I actually found my way here after seeing your review on your website. Just bought the Redcat and looking forward to trying it out. With everything WO thought about in this unit I'm honestly surprised that they didn't incorporate a left hand thread on the T-ring mount. That way when you attach your DSLR you would be "tightening" the T-mount into the telescope rather than loosening it. Other than that, I can't see any downsides to this telescope at all.

[@annihilator1983]

baboom, glad you took the advice on the WO skyguider pro upgrade kit

[@MiguelMoerman]

Supernice review! You convinced me to buy a RedCat 51. Thanks

[@n8hills]

This was a very thorough and informative review! I'm a newbie taking my first steps into astrophotography and after watching this I just ordered the RedCat 51! (I like the color red) Now I need to get a tracker. Thank you for this review!!

[@traviscallahan7178]

Saving up to do the same thing, please post here what you think of it. Have a great day :)

[@tannhaeuser]

Same situation here. What can you tell us about the RedCat now after 2-3 years of use?

[@danielmulvihill5927]

I had the same issue with my Nikon T-adapter. I removed the tiny silver screw that acts as a stop, and it now works just fine. No issues since.

[@baszonneveld7740]

This is the best no nonsense review i've seen! Gonna get me one as well. Clear skies!

[@baszonneveld7740]

Got me one and it's....super! Nice build quality and razor sharp pictures. Happy ;)

[@chrisnurnberg9599]

I think this would be my first Astrophotography set up. Looks great.

[@Microtonal_Cats]

I want one, if even just for the "cats in space" whisker reticle.

[@sergep5563]

Always useful and interesting, just a bit difficult to understand everything - but with subtitles it gets easier... :))) hi from Italy

[@Mr6sess]

Very helpful in many ways. Thanks for sharing!

[@davestephen7647]

This video clears up a few things for me, for the most part. Apparently there are no user manuals, not even straight from WO, electronic or hard copy (Spacecat). I had been wondering about the filters. I would have gotten the wrong size (48mm).

[@phillipjones4743]

Great review. You hit on the subject that has kept me away from WO products: their customer service. My first and only product I purchased from them was defective. They refused to honor the warranty. So now this great little imaging scope has my attention, but I am hesitant to purchase.

[@NathanThompsonBlueEyes]

How could they refuse? It's their product with their name on it, right?

[@astrogerard2022]

Another well spoken review. Thanks.

[@miroslavk.5049]

Excellent review, thank you!

[@ramiroquai1820]

Thanks for your awesome review! What about pairing this lens with a Fujifilm XT3??

[@chhupparustom]

A very concise and to the point review covering all relevant aspects. Regarding the WO support - I have emailed them with questions and they were pretty prompt. Looking forward to its review with same setup but with dedicated astro-camera.

[@RafaelSwit]

Excellent review as always! For those of you who already have a Full Frame camera, do not worry that you may need to buy APS-C or other crop camera. The focal length multiplier you get with smaller sensors, can be easily accomplished on a full frame camera by either enabling crop mode in the settings (some full frame cameras have that option) or simply cropping the image in editing software. To avoid vignette just keep your target object as close as possible to the center of the frame when capturing photos. In most cases full frame cameras will offer you better performance when using higher ISO. But in the end, use what you already have... in the past many astrophotographers imaged with cheap webcams with great results.

[@PeterZelinka]

Thanks! Yeah, hopefully that's not the impression folks are getting, that you need a crop sensor. However, there is a difference between using a crop sensor and full frame camera. A crop sensor usually has smaller pixels. This translates to worse low-light performance, but also "more zoom" than a full frame camera. You cannot replicate this by shooting in crop mode with a full frame camera. I recommend looking up arc seconds per pixel for more information.

[@JasperJanssen]

Peter Zelinka just to add to that a little: this is true when comparing similar generations of cameras, costs, and megapixel counts. If you’re comparing across years - such as when you’re comparing what you already have to something you might buy - things can be very different. Old APS-C sensors have huge pixels, even compared to modern FF sensors. And you can certainly make full frame sensors with pixels just as small as most APS-C sensors - they’re just going to be very expensive. Not sure if anyone actually does make them for products.

[@rackmasterh]

At these focal lengths you are under sampled, period. So pixel size didn't matter except for full well depth. Examples: a 3 micron pixel is about 2.5 arc sec/pixel and a 5 micron that time 5/3 or 4. With decent 2 arc sec seeing you are undersampled in both even assuming perfect tracking. If that bothers you drizzle stack and it won't matter at all.

[@tigercloud6945]

My redcat showed up yeserday. And is cloudy....lol. ty for the video can't wait to get a cloudless night.

[@strelnikoff7]

Thread pitch on T-adapters and receptacles make them stuck very often. And it’s annoying and hard to break that connection later.

[@CountCarbsNotCals]

Peter, you are a godsend, thank you.

[@michaelmckeag960]

It is not "free magnification." It is a cropped image. You can produce an identical result by cropping an image taken with a full frame camera with the same pixel pitch as the APS-C sensor. This is confusing field of view with magnification. Image scale is determined by focal length and pixel size (arc-sec/pixel). Sensor size just determines the field of view not magnification.

[@Lou_Zasil]

best review of this telescope hands down. going to check out your others videos now and sub if i likes what i see's

[@sgifford1000]

Excellent review!

[@azuren4242]

Spot on. I loved your review!

[@astrophemeris2958]

First of all, very nice review of this bad boy. Second of all, you mention a couple of times the benefits of using crop sensor dslr due to the fact that I would naturally get rid of vignetting and corners distortion. Does it mean that, using my crop sensor dslr, I don't really need a field flattener? (I'm just worried about heavy coma in the corners) Thanks in advance ^^

[@GrowingAnswers]

Versus a lens with f2.0, how much longer exposure time is needed with an f4.9? I understand stops, but I’m not sure how much that matters with Astro.

[@MarvelousLXVII]

Great review!

[@AnakChan]

Did you get a chance to play with the tilt adjuster?

[@briankelley7918]

I try to do my homework with companies and one of my first steps is how is customer service. For the price they should have contacted you. thank you for letting us know that.

[@none-id3lj]

So what is the actual difference between a "normal" lens and a telescope like this one? Like, there are some decent lenses that are cheaper with good F.

[@yellowlynx]

The orginal bainov mask does not use the transparent plastic like the William Optics version does - the diffraction lines are the same but much shorter and dimmer. William Optics improved on it and the lines are longer and brighter.

[@-_--rb6xq]

How would I attach a 2in filter to the back of the spacecat

[@johannburgher1214]

You are very good. Continue the good work.

[@noseonscent1935]

Thanks for telling the truth, something that seems to be going out of style. Sorry to hear about Williams Optics non-existent customer service but their quality is very obvious. Great channel, great video. Cheers

[@nelsondecker2124]

, really like your videos they have been extremely helpful. Is your Space Cat any good for birds in flight. I shoot with a Canon 90d and Canon 1dx Mll with either a canon 100-400mm or a Tamron 150-600mm. Would the Space Cat be an improvement? thanks Nelson

[@MoonbeamArcade]

Thanks for the great review! I just started astrophotography so I'm learning as I go. I use a Sony A73 and one useful thing on that is you can assign a button to toggle between full frame and aps-c mode, so once you find an object in the sky you can switch to the 1.5x aps-c crop and zoom in closer with the same lens. One thing I was curious about, are the optics better on lenses like this SpaceCat compared to quality Sony prime lens, or is buying an astrophotography lens more about the other stuff you mentioned like being able to rotate it, etc?

[@PeterZelinka]

It really just depends. But, actually many lenses are more well built than telescopes (which is why they cost so much more!). For example, a 70-200mm usually costs between $1,300 - $3,000. Mainly due to all the corrective elements inside. A telescope usually doesn't have many of those, and a telescope won't open up to f/2.8 either. That's why they are generally cheaper and lighter. Frankly, you can get fantastic photos with a telephoto lens you may already have. There's not necessarily a benefit to using a telescope (beyond the nice features that may be included - bahtinov mask, dovetail plate, guide scope mounting bracket, etc...)

[@sirmeowcelot]

Got mine in February and it worth every penny.

[@dwulf3949]

So i have a question to anyone that can answer. Do you need to buy both adapters ? The one for your specific camera i realize is a yes but does the red cat come with the adapter that that screws into or do you need to purchase both on the side ? Thanks for any info. Just getting into Astro-Photography.

[@woodywoodman4309]

So glad to see you post this review. I have a Spacecat 51 being delivered tomorrow along with the Star Adventurer. I'm interested in what targets you think would be good for this telescope?

[@PeterZelinka]

Pretty much all of the targets I cover in my Deep Space Course. Orion, Rosette, Veil, North American, Horsehead, Andromeda, etc... Although, as I mentioned, the 250mm focal length is a bit short when paired with a full frame camera.

[@woodywoodman4309]

@@PeterZelinka Thank you for the reply. I have an A7S full spectrum camera, an A7iii and I just picked up a used A6500 to pair with this setup to get that extra reach. Thanks for all your helpful videos, happy holidays to you and yours.

[@elizabethmacharia9786]

Thank you Peter

[@ankitkhandelwal7372]

Hey Peter..!!! Wanted to ask you the better option between such telescope and telephoto lens...being a beginner which option should one go for?

[@Arquidron]

Hi, has anyone used this equipment with a Nikon Z6, what results have you had?

[@Rainy78]

So the red cat/space cat with dslr/mirrorless will be fine on an ioptron pro/skywatcher and basic tripod? How much for that setup, minus the camera? Im looking to continue astrophotography with an actual dedicated astro lens. Would you recommend this setup? I have a nikon 300mm f4 prime. Will the red cat differ in a better way? I dont know what to get to start off with lens/mount wise. I dont want to keep upgrading and spend 50k lol. Thanks for sharing!

[@radon4267]

I'm thinking about buying this beautiful thing - do I need any extension Tubes to get in Focus?!

[@scottphoenix8298]

Hi, I'm new to astrophotography, do I need autoguiding for the redcat 51 or space cat? Or would I be able to take 1 to 2 hours of 90 second/2 minute exposures without autoguiding? I have a star adventurer star tracker and I'm looking into buying a Redcat 51 but I don't want the extra cost of autoguiding and the hassle of having to use a laptop, thanks.

[@astroterrace]

Peter, can a mirrorless camera be attached to this telescope?

[@josepsalvadorpontsanjuan4869]

Great video as always! Can you tell us wich one have more quality image between spacecat and tamron 150-600? Thanks man!

[@PeterZelinka]

The Space Cat is definitely sharper and has less vignette. However, I do enjoy the big zoom range on the 150-600mm

[@DamianVines]

Peter Zelinka Considering I already own the Tamron 150-600, would you say that the redcat 51 is a reasonable upgrade or might that money be more well spent on a dedicated cooled Astro photography camera?

[@PeterZelinka]

@@DamianVines Well, I would initially say that you're much better off investing in a dedicated astro camera. However, I don't know how well it would pair with the 150-600mm. You'd have to get the ZWO adapter to connect them, and might have trouble focusing. Also, you may have problems with the aperture, since a dedicated astro camera may not properly communicate with the lens. I think the RedCat would pair quite nicely with a dedicated astro camera, as seen by Stu's photos at the end of the video. Plus, it would be a much simpler connection between a telescope and a dedicated astro camera. The 150-600 works great paired with a DSLR, but I wouldn't want to use it with a dedicated astro camera. Hopefully that answers your question!

[@flyingmedic]

Absolute spot on review. I did my PhD in astrophysics many years ago and having shifted to medical doctoring I lost touch with my first love. This helps me back to astrophotography. At least the subject matter will not of aged as much as I have :-) Thank you. Paul

[@abduld]

great video per usual. what about using crop mode on a full frame camera? like dx mode on Nikon or aps-c mode on sony? same benefit as using a crop sensor right?

[@PeterZelinka]

No, the crop mode doesn't really do much. It's actually the worst thing you can do haha You're better off shooting in the FX mode, and cropping later in post. I recommend reading my written review (see the pinned comment) for more information on this. The smaller sensors will give you better results than simply cropping a full frame camera photo. The only downside is that the crop sensor camera's have smaller pixels (which is what gives you the "extra zoom"), but these smaller pixels capture less light. Therefore, you need to take longer exposures. Long story short, DX mode does nothing beneficial it only limits you. It's better to actually get a crop sensor camera.

[@abduld]

@@PeterZelinka i appreciate the response. you do a great job with your videos, we're lucky to have you!

[@Steve-ff3xx]

Nice review. Concerning your comment about the size of objects when using a full frame sensor vs smaller sensor on the SpaceCat, It seems to me that with the full frame sensor you have the option of cropping the image down to any size you want. A full frame sensor also lets you use the wider field of view when you find that it is beneficial to do so. So I am not sure I understand your point about the disadvantage of a full frame camera when used with the SpaceCat.

[@rackmasterh]

Right, see my comment also. He is just dead wrong. Sully realky.

[@shaunsprogress]

The TMount should have a small screw on the front. You need to just turn it half turn anticlockwise so it engages with your lens release mechanism. It's not defective, it's just not protruding far enough.

[@PeterZelinka]

No, I've confirmed this particular T-Mount is defective. William Optics has discontinued it and released an updated version that works fine. I've also gotten reports from other people who have the same defective T-Mount and have the same problem. Hopefully they are able to get replacements too, as this is a very serious problem.

[@NeilW210]

Looks like a great astro scope, but I'm not sure how WO can market this as also being a potential bird photography lens, not unless the birds are very compliant. A fixed aperture lens with manual focus certainly wouldn't be ideal. Most wildlife photography needs rapid autofocus with the ability to set varying focus points and focus methods. along with the ability to vary aperture. Excellent review though Peter...thank you.

[@PeterZelinka]

Hahaha same here! I saw that was one of their selling points, but I didn't see the point in even attempting it. If I'm doing wildlife, the 150-600mm is the way to go!

[@CountCarbsNotCals]

I'm going to put together similar setup, do you recommend a mirrorless DSLR or ZWO cam (which one, since I have neither?) ?

[@PeterZelinka]

If you plan on getting the RedCat telescope, I would recommend a ZWO cooled camera. This will have a smaller sensor and smaller pixels than most DSLRs. In other words, you'll basically get more zoom!

[@itaialter]

Hi Peter, I have a question regarding what you mentioned about the Canon Rebel series. I have a Canon 550D (T2i), and while it does have a (1:1) Movie Crop Mode for video, I'm not sure how to do the same for Still images. Or is it a permanent state? (every lens on that camera is already cropped?) Thank you!

[@PeterZelinka]

I don't recommend using crop modes in-camera. All that is doing is cropping ahead of time, when you could do it yourself in post-processing. I'd rather have the full image area to work with in-camera.

[@fernandoisidoromalmoria8848]

Hi Peter, thank you very much for sharing your knowledge. I would like to ask you the following: I have a Tamron 100 400 that I use with a Star adventurer mount, is the purchase of a telescope similar to the Skywatcher 72 ed justified to replace the Tamron? Can you perform better with the telescope? Thank you very much, regards. Fernando

[@PeterZelinka]

Unless you are noticing bad coma (star distortion) I would not get a telescope. I've been able to capture great photos with a standard camera lens!

[@mikeries8549]

One night I was taking pics of the moon and there was a big blob. (Ufo) So I changed lens and it's still there. Was a little bit of dust on the sensor. One puff and it's gone.

[@c.dirosa4088]

Hi Peter. Thank you for your very helpful video review! I got the RedCat months ago, before the September version came out. I have the same problem that you described with the T-Mount adapter. My Canon 60D wont click into place and will slowly twist off under it's own weight. Did WO eventually respond to you and replace your defective T-Mount? Also, do the 'upgrades' to the later version include anything to do with the optics and/or the focuser? Thanks again.

[@PeterZelinka]

Nope, I've still never heard from William Optics. Who did you buy the T-Mount from? A third party or from WO directly? If you purchased from a third party, I'd contact them, since this is a discontinued and defective product. As for the upgrades, I don't believe there was any real change in optics. The focus ring has some more precise markings, but not much beyond that.

[@c.dirosa4088]

@@PeterZelinka Thank you Peter for the quick reply. I got my RedCat through Kick Starter, which WO was using (evidently) to raise funds for product development. So there was no dealer involved. The RedCat was shipped directly to me. After I watched your video yesterday I sent WO an email, asking them to please replace the defective T-Mount adapter. I hope they reply.

[@PeterZelinka]

@@c.dirosa4088 Good luck! Let me know if they get back to you!

[@screwyouyoutube5493]

Although I really like the Redcat 51, with my 1600MM pro ,the biggest issue i have with it is the oversampling.

[@insightvideo6136]

Do you need a flat field reducer for the Space Cat or Red Cat scopes? Thanks for the great videos!

[@buzzsawddog]

Nope

[@kevinjack5184]

Sounds cool, but I just ordered the e mount sigma 100-400. Too bad it's on back order

[@Mike-lh4wn]

So this leaves the question...how does this compare with other DSLR lenses for astro? Considering price, capabilities, flexibility of use...and a finite amount of spending cash...would you recommend having a WO Cat over a good prime or zoom lens (rokinon, sigma, etc)? Or would you classify the WO a 'nice to have' lens...after already having some other good lenses.

[@PeterZelinka]

Depends which lenses your comparing it to really. If you've already got a good zoom lens over 250mm, and it has minimal chromatic aberration and coma, there's no real need to get the Space Cat. However, if you don't have a nice zoom lens yet, and are looking for a relatively inexpensive telescope, then the Space Cat is a good choice. It's also much better designed than the Z61, which almost feels junky by comparison (between long flat field adapter, the lack of a dovetail plate, bad balancing with a DSLR, etc...) I have a 70-200mm and 150-600mm lens. I'll still use both of those lenses at night, since I can get different compositions by changing the focal length. Once I get a monochrome astro camera and filters though, I'm going to use the Space Cat as my main lens at night.

[@LB-gt1si]

I have the original Redcat and it does have coma issues. I returned the first I got and replaced it with another one. It performs better but still has coma. I do not have a full frame camera. I use a Canon rebel T3i APS-C sensor, and coma still exists. Now to my question. How did you make the vixen plate work with Ioptron's vixen style saddle? I know it sounds like a stupid question but mine are not the same size. I had a discussion about it in a post on Cloudy Nights forum. www.cloudynights.com/topic/680143-my-first-m31-photo-and-a-question-about-vixen-mount/?hl=redcat+51#entry9705741 It was stablished by measuring the plate that WO is to blame as it's not the standard vixen style size plate. Thank you Leo and Lisa

[@subhadipghorui2216]

Whats is better 70 200 f2.8 or this telescope ?? Can you compare it with a DSLR lense?

[@PeterZelinka]

Check out my written review for more information. In short, a 70-200mm lens does a good job in most cases. However, the focal length is usually too short, especially when paired with a full frame camera. I usually recommend around ~400mm for deep space astrophotography with a DSLR

[@GenCodeFPV]

Peter, why not just get a 350mmm sigma lens for a full frame instead? I have a Z6 and am trying to decide on a Space Cat/Red Cat. Also I have a Z mount not a F Mount, do they make a Z mount adapter for the Space Cat? My Z6 can go into crop mode to emulate a crop sensor so that should help.

[@PeterZelinka]

You could go that route, but Sigma lenses generally tend to have bad coma and chromatic aberration. I'm actually not sure if they make a Z Mount or not. I don't recall seeing that as an option. There seems to be a lot of confusion with this crop mode on full frame cameras. I'd recommend reading my review (see the pinned comment) for more information. It should clear up the difference between using a full frame camera and a crop sensor.

[@MarkoPola]

12:38 😧 saved by the dew shield 😅

[@VittorioSergi]

Man, I feel you, the whole liveview business is just a nikon thing man, every canon dslr since...2011 basically autoadapts liveview brightness to compensate

[@michaelmirecki3114]

I have no problems with the D750...

[@chandra5103]

got the T mount M48 mm from WO and have the same issue as you had, Peter. Unbelievable .. they have one on their site as "discontinued" and I thought I would get a normal but got defective again .. they only now can do a refund if I will send it back to Taiwan .. uhhhh

[@FredSchmitthammer]

What scope field of view size telescope is best for full frame camera?

[@PeterZelinka]

I personally like 350mm - 500mm for my deep space astrophotography. I think this is just enough zoom to make the objects appear large in the frame, without going too far. Once you get to 200mm, it's just not enough zoom in most cases (at least on a Full Frame camera).

[@FredSchmitthammer]

@@PeterZelinka Thank you! I plan on a RedCat 51. This on my Canon 5d mk4 should do OK. Right? I also have a Tamron 150-600mm that should work also. My mount is an eq6r.

[@blueRC]

I think Canon crop sensors also have a crop factor of 1.6, Sony has 1.5

[@SuperBuickregal]

Your right 1.6

[@fazergazer]

Satisfying click at 12:45!

[@jameswoods1939]

Ordered a Redcat from Highpoint and have attempted several times to contact them via email and phone.... never hear anything from them. May just be the current industry.

[@birreboi]

The Redcat 51 certainly had some good reviews, but also some bad. Looking at some astro forums a couple of months ago, (SGL for eg) there was quite a number of complaints and returns of the Redcat 51. I *think* from memory, problems were mainly due to excessive coma. Though, to be fair, that may have been a problem in the initial production of this scope. Still, has made me think twice about buying a WO scope.

[@rainerhofmeister6648]

Had the same on my WO 110 Triplet, horrible coma. I had to send the lens assembly to Taiwan for repair. Didn't cost anything, but was a lot of hassle. Came back perfectly aligned.

[@davidperry7128]

I think the bad reviews were for the original Redcat, they have addressed the issues with the updated version. There is a tilt adjuster on the updated version.

[@danwray5626]

Since the Space Cat is only 250mm I don't see how you can get an image like the one at the end of the video. I have been using a 280mm lens and the Orion nebula is disappointingly small.I don't see how you can fill the frame with even 500 or 600m as your written review suggests. What am I missing in this picture?

[@PeterZelinka]

I don't know what to tell you haha, that image was taken with the Space Cat and Nikon D750. I cropped the image to a 16x9 ratio, but I didn't crop in. Check out my website for my other Orion photo, the one that's all purple. That was taken at about 500mm and cropped slightly.

[@danwray5626]

@@PeterZelinka Thank you very much for the reply. I saw the other examples on your website. I also shoot with a full frame camera but at 280mm the Orion nebula is so very small. I don't know how to account for the difference. Mine are single shot photos as this time, but soon I will use tracking.

[@branislavmikuska1907]

Hi Peter. Sometimes, 250 mm is not enough. Is it possible to combine cat with barlow?

[@PeterZelinka]

Great question! To be honest I'm not sure. I don't have any Barlow lenses and I've only used them once a few years ago with another person's telescope.

[@branislavmikuska1907]

@@PeterZelinka Thanks for reply. I was googling, but I wasn't successful. Maybe during the time, someone will try it :-) By the way, thanks for another great video 👍

[@xe1zlgg]

Agree 100%.

[@mahmoudelsaid3552]

can it work with Nikon Z normally or I would need the FTZ adaptor

[@PeterZelinka]

I believe you'll need a special adapter, but I'm not sure

[@bryandixon4071]

A few other reviewers had a z6 and used the FTZ adapter as there isn’t a tmount adapter for the z mount currently

[@dhruvmishra2221]

Hey Peter. I am a bird photographer and I am using nikon d5500 with nikon 300mm f4. can this equipment be used in astrophotography? I will buy a euatorial mount if it is possible.

[@PeterZelinka]

Yep! I usually recommend people start with the gear they already have. A D5500 and 300mm f/4 lens will do an awesome job for astro!

[@dhruvmishra2221]

@@PeterZelinka thanks a lot :)

[@sebastienb.5985]

Nice beginner kit.

[@BrokenPik]

Very nice lense...

[@rfcdgaf]

Biggest problem with these apo scopes is the F/5. I wouldn't bother with these when you can get a 200mm f2.8 or 300mm f2.8 for less than what this costs. For star trackers, speed is everything

[@RaysAstrophotography]

Besides William optics customer service and the T ring issue that you had mentioned seems like a good looking travel telescope to me!

[@PeterZelinka]

Yep! That's why it appealed to me, I spend 6 months living out of my car and traveling across the country. There was no way I could bring anything larger than a Z73, so the portability of the Space Cat is a huge plus!

[@RaysAstrophotography]

@@PeterZelinka I like your down to earth honest review! Well done!

[@siegfriedberger7009]

Hi Peter, I haven't got the real advantage compared to the Tamron 70-200 G2 or the Sigma 150-600 C?

[@josepsalvadorpontsanjuan4869]

Siegfried Berger yeah, i’m interested too

[@PeterZelinka]

If you have one of those lenses, you don't really need the Space Cat. Almost all of my deep space photos were taken with a telephoto lens, and they turned out quite nice. This telescope is really for folks who don't have a nice telephoto lens yet. Instead of spending $1,200 - $2,000+, they can get the Space Cat for ~$750 and get some great astro shots. If you're a serious photographer though, I do recommend investing in a good 70-200mm and 150-600mm lens. I've gotten some of my favorite photos (landscapes, wildlife, and astro!) with those focal lengths. If you have a dedicated astro camera, I think it would pair great with the Space Cat (as you can see from Stu's photos at the end of the video). Mounting a dedicated astro camera to a lens would likely prove more difficult

[@WayneLouie]

Is this setup too heavy for Move Shoot Move?

[@PeterZelinka]

I would not use any telephoto lens with the Move Shoot Move. That tracker is best with wide angle lenses

[@WayneLouie]

@@PeterZelinka Got it. Thanks!

[@book3100]

Cats whiskers are a Bhatinov pattern

[@lubossoltes321]

A reversible lens hood ? Who would have thought about that ....

[@PeterZelinka]

hahaha fair enough. I'm just glad they gave the option to use it, remove it, or reverse it. Portability is one of the main attractions of this telescope after all.

[@rcraigmacrae]

I just heard from William Optics that the SpaceCat51 is no longer being produced. You can only order the RedCat51.

[@izanagisburden9465]

If there is no difference except the asthetics I have no problem tbh..... I kinda like the red one more anyway

[@TheFredo065]

Wow!

[@tortuga7160]

What is the object at 14:11

[@parttimedogfish]

Looks like the Veil Nebula

[@tortuga7160]

@@parttimedogfish Thanks for taking the time to answer that, looks like you're right. Beautiful target!

[@TheRattleSnake3145]

These things are never in stock!

[@keshv3883]

lol thats because its a limited edition

[@TheRattleSnake3145]

@@keshv3883 then they should take them off the site.

[@keshv3883]

Which site lol

[@MacEliot]

Peter. WO is really responsive using the Line iOS app; find them on their official Line account (William Optics). Give that a shot.

[@PeterZelinka]

I'm on Android so unfortunately that won't work (unless it's on Google Play too)

[@MacEliot]

Peter Zelinka it should be on Android, too. But you are right that their customer service is hit or miss.

[@tinkmarshino]

no customer service = not being a customer... thanks for the info..

[@oskargydell5813]

Hey Peter! I know you use the Tamron 150-600, but do you have any experience of the Tamron 100-400? I use the nikon 70-200 today but looking to go even further into space :P, Great review on the Spacecat btw, tempting as well. :)

[@PeterZelinka]

I'm not familiar with that lens, is it for Canon/Nikon cameras, or mirrorless?

[@oskargydell5813]

@@PeterZelinka Hey. Its for nikon. I use the d850. I found some more info and it seems that its not really an option. I think I will go with the Redcat and maybe the 150-600 as well. :)

[@PeterZelinka]

@@oskargydell5813 the RedCat is gonna be fairly short for the d850, you may want to get the 150-600mm first. You'll be able to fill the frame with a lot of objects at 400mm+, rather than the 250mm of the SpaceCat

[@oskargydell5813]

@@PeterZelinka Thanks for that tip. Yes I feel that my 70-200 is a bit short atm. Hopefully the Star adventurer Pro can handle the extra weight of the 150-600. :D Cheers