William Optics RedCat 51 APO

[CCD Imager]

4 hours ago, FLO said:

It is good to hear you saw an improvement but I promise you there is more to collimating a 4-element refractor than simply tweaking a few screws. It is not like collimating a Newtonian. Your supplier should do or arrange the collimation for you.

I don’t want to sound melodramatic but, seriously, if you encourage people to collimate their RedCats it will almost certainly end in tears. Please don’t. 

Steve 

Steve's right, you need to be knowledgeable about optics before attempting collimation of a refractor, especially ruling out other potential causes of mis shapen stars in an image.

[Adam J]

Yes don't do this, you are adjusting the front element but you cant even be sure that is the one that is out of place, for all you know its the rear element pair and you just changed moved the front element out of alignment. 

[CCD Imager]

1 hour ago, Adam J said:

Yes don't do this, you are adjusting the front element but you cant even be sure that is the one that is out of place, for all you know its the rear element pair and you just changed moved the front element out of alignment. 

As the rear elements are fixed at the factory, they are very unlikely to move. The front two elements are adjustable and would be the likely source of any miscollimation, as it was in my case. I had an FSQ with exactly the issue you describe and that needed to go back to Japan and I had a replacement. I don't have much luck with small refractors!

[Adam J]

41 minutes ago, CCD Imager said:

As the rear elements are fixed at the factory, they are very unlikely to move. The front two elements are adjustable and would be the likely source of any miscollimation, as it was in my case. I had an FSQ with exactly the issue you describe and that needed to go back to Japan and I had a replacement. I don't have much luck with small refractors!

I know what your saying and to an extent there is a point at which it can be so bad that you can only make it better no matter what you do, but those rear elements can still be poorly seated and if its that bad just send it back as that way you will not infringe the warranty.  

 

[Space Oddities]

Just came across this picture of the "Space Cat" on Instagram. Looks like a v2 of the William Optics Red/White Cat, with a different collar and a handle (with funny cat ears!)  

The specs seems to be the same, as stated by the poster:

Quote

EQUIPMENT:
William Optics SpaceCat51

250mm / f4.9

 

 

 

Edit: I have found a page on Cyclops Optics with additional information and pictures. It seems to be a limited edition, available in pre-order and released (possibly) in October: https://www.cyclopsoptics.com/telescope/william-optics-spacecat-51-limited-edition/

 

Quote

Exclusive features of the SpaceCat 51 APO:

• Limited edition space grey colour scheme
• Extended length dual spec mounting base (Arca/Vixen)
• Focal plane adjustment ring (O-ring)
• SpaceCat special edition carrying bag

Optional: SpaceCat Handle Bar (US$45)

Supports William Optics new unibody guidescope

 

Edited September 2, 2019 by Space Oddities

[FLO]

New William Optics SpaceCat telescopes are incoming. Perhaps only 1-2 weeks away 🙂

Steve  

[Buzzard75]

The mounting base is probably my biggest complaint with the Redcat. It doesn't quite work with my iOptron mount since the saddle clamps are of a split design. Regardless of which way I mount it, I can't balance the scope with camera and a filter wheel and have it sit in both clamps. The new base on the SpaceCat may be a result of that. I think I'm going to have to get a different mounting base.

Cool design though.

[Space Oddities]

3 hours ago, Buzzard75 said:

The mounting base is probably my biggest complaint with the Redcat. It doesn't quite work with my iOptron mount since the saddle clamps are of a split design. Regardless of which way I mount it, I can't balance the scope with camera and a filter wheel and have it sit in both clamps. The new base on the SpaceCat may be a result of that. I think I'm going to have to get a different mounting base.

Cool design though.

I have the same issue with a mounting base I bought from them. It's not large enough and therefore, not compatible with some saddles. I only use the Arca-Swiss side now, which kind of defeats the purpose of this base. Pity, because it's pretty well made!

[Buzzard75]

2 hours ago, Space Oddities said:

I have the same issue with a mounting base I bought from them. It's not large enough and therefore, not compatible with some saddles. I only use the Arca-Swiss side now, which kind of defeats the purpose of this base. Pity, because it's pretty well made!

Here's an image of the CEM40 saddle. The two locking blocks with the locking bolts are separate. Just having the dovetail held in place with one of them doesn't seem adequate. And the way my Redcat balances out, the end of the dovetail always falls short of one of those blocks. If it's towards the front of the scope, I miss the rear locking block. If the dovetail is mounted toward the rear of the Redcat, it misses the front block and will actually probably interfere with my filter wheel. The dovetail doesn't need to be too much longer, just a little bit. If they had made an adjustable notch in the middle of the bar rather than on either end, it would have been perfect. Hindsight and now a design change.

Edited September 3, 2019 by Buzzard75

[Nikolas74]

I am using an ADM Saddle upgrade on my HEQ5 Pro....I had to change the dovetail bar to a longer one from ADM....to make it balance.....

But I think it's an excellent lens/telescope...

What I was disturbed about its the price which now I believe it's too high.....

[Space Oddities]

Just noticed the Cat 51 accepts 55mm filters in front of the scope. That's very convenient for me, I had a spare 58mm LP filter that I can now use with the Cat, thanks to a 55-58 step-up filter  

Here is a picture!

[Tayson]

Hi.

 

Few days ago I bought new WO RedCat.

First light was with Canon1100d. Only 10minutes between clouds. At testing frames I see some strange black strips on stars.

What is it?

 

center of frame

 

I checked colimatnion on artificial star 25um, 15m from cat. Its looks correct - all corners and center are similar. 1/8s exp, ISO800

No weather for more stars test  

 

[Space Oddities]

Perhaps screws protruding inside the lens?

The Z61 has a similar issue I believe, and if I remember correctly, this is more visible as the temperature gets lower...

[Tayson]

 

3 minutes ago, Space Oddities said:

Perhaps screws protruding inside the lens?

The Z61 has a similar issue I believe, and if I remember correctly, this is more visible as the temperature gets lower...

thanks.

Can You tell me which screw ? Where are they?

[Space Oddities]

Hmm I just checked my cat, and couldn't see any screw visible inside the lens... But the spikes really look like the ones described here, for which the cause seemed to be collimation screws:

 

 

[Tayson]

How much I shoud release those screws? 1/4 or 1/8turn?

Any idea?

[david_taurus83]

Are we talking about the collimation screws here? I wouldn't be messing with those! I had the same with my WO GT71. I wonder if its anything to do with WO trying to squeeze every millimetre out of the objective width. In contrast, I've had 3 Altiar scopes and they all quote 1mm less than their WO counterparts ( Altair 102mm -WO 103mm, Altair 70mm - WO 71mm, etc) and I've not noticed the issue with the Altair brand. Here is an example of a bright star in M45. This was only ever evident in bright stars and it didn't ever bother me btw. Was still a quality scope.

[Space Oddities]

Yep, I wouldn't touch the collimation screws either! 

I've looked at other pictures of Redcat, as well as mine, and couldn't find such spike anywhere. For example these pictures of Sadr:

https://cdn.astrobin.com/thumbs/bQqyD19ggn6-_16536x16536_kWXURFLk.jpg

https://cdn.astrobin.com/thumbs/EFKOfqbrkFTH_16536x16536_JXczOqwr.png

Perhaps your copy is simply faulty and is eligible to an exchange? Unless you can live with it!

16 hours ago, david_taurus83 said:

Are we talking about the collimation screws here? I wouldn't be messing with those! I had the same with my WO GT71. I wonder if its anything to do with WO trying to squeeze every millimetre out of the objective width. In contrast, I've had 3 Altiar scopes and they all quote 1mm less than their WO counterparts ( Altair 102mm -WO 103mm, Altair 70mm - WO 71mm, etc) and I've not noticed the issue with the Altair brand. Here is an example of a bright star in M45. This was only ever evident in bright stars and it didn't ever bother me btw. Was still a quality scope.

Hmm I don't think that's the case, and I believe it's just a naming convention. I'm pretty sure all these variants are optically identical. I have the TS 60ED, which is a rebranded Zenithstar 61, and both scopes show spikes on bright stars anyway 

[AstroRuz]

Ooh this looks lovely. Hopefully that will drive the price down of the original RedCats and then I'll be able to afford one! haha. Always wanted a cat telescope.

[Tayson]

On 16/12/2020 at 10:27, Tayson said:

Hi.

 

Few days ago I bought new WO RedCat....

I just a litte bit release front ring.

much more better!

 

Canon1100D.