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WO RedCat 51: comments, observations, opinions and suggestions

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#51 AnakChan

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Posted 17 August 2019 - 09:22 AM

Now that the RedCat 51 has been out for quite some time and more folks have received them, I’m wondering how severe is the tilt issue with it? K-Astec/Y-Tomita in Japan sell RC51 package with a tilt adjuster and I’m wondering if the tilt adjuster is truly needed or has WO sorted out all those issues?



#52 weh

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Posted 17 August 2019 - 10:03 AM

... tilt issue with it? ...

There appears to be a slight amount of "slop" in the focusing mechanism. I've found that tightening the focus ring lock pretty much resolves the issue -- maybe not for really critical work, but close enough for my needs thus far. Caveat: I'm a pre-beginner.



#53 josh smith

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Posted 17 August 2019 - 10:16 AM

Now that the RedCat 51 has been out for quite some time and more folks have received them, I’m wondering how severe is the tilt issue with it? K-Astec/Y-Tomita in Japan sell RC51 package with a tilt adjuster and I’m wondering if the tilt adjuster is truly needed or has WO sorted out all those issues?


I’ve yet to see one image from that scope that is truly flat to the edges even on a small sensor. I’m still fiddling with mine and would love to see it work, but no luck so far.

#54 AnakChan

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Posted 17 August 2019 - 11:49 PM

Cheers for the response folks. The reason I'm asking is that K-Astec only made 30 of these (and I believe they're not sold out yet at Y-Tomita). It sounds like having a tilt adjuster for the RC51 is not only just a nice-to-have but will have practical benefits. I read in a blog that the "House of Y-Tomita" is closing, and I don't know what that means (i.e. I'm hoping it's just their observatory, not their shop...but if it's their shop too, then no more of these K-Astec tilt adjusters for the RC51).



#55 josh smith

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Posted 18 August 2019 - 07:49 AM

Cheers for the response folks. The reason I'm asking is that K-Astec only made 30 of these (and I believe they're not sold out yet at Y-Tomita). It sounds like having a tilt adjuster for the RC51 is not only just a nice-to-have but will have practical benefits. I read in a blog that the "House of Y-Tomita" is closing, and I don't know what that means (i.e. I'm hoping it's just their observatory, not their shop...but if it's their shop too, then no more of these K-Astec tilt adjusters for the RC51).


Have you seen any samples of images using the adjuster that have flat fields?

#56 AnakChan

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Posted 18 August 2019 - 09:16 AM

Have you seen any samples of images using the adjuster that have flat fields?

 

Unfortunately no sample images of images from the adjuster.

 

http://k-astec.cocol...ost-074040.html



#57 Lead_Weight

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Posted 18 August 2019 - 04:46 PM

I couldn’t see a price. Anyone know what this cost?

#58 AnakChan

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Posted 18 August 2019 - 06:17 PM

Sold as a set but not certain if they’ll sell overseas. This is in Japanese only :-

http://www.y-tomita....ited_spset.html

#59 Seanem44

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Posted 20 August 2019 - 07:21 AM

You're welcome to look at my image.  I am very pleased with the flatness.  I have only the slightest of coma in the top right corner, only perceptible with extreme pixel creeping.  I may have just won the optical lottery, I don't know.  My scope was built on 7/18/19

 

https://www.astrobin...420567/?nc=user


Edited by Seanem44, 20 August 2019 - 07:22 AM.

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#60 josh smith

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Posted 20 August 2019 - 07:45 AM

Thanks, Sean.  It's certainly very solid and relatively flat.  (Very nice image, btw)  

 

However, every corner is still showing elongation to some degree and that is in narrowband with less than an APS-C sized sensor.  Broadband would highlight and accentuate that even more.  I think the scope is a great value for the money, but it certainly doesn't seem to meet the product description, which is fine to me...  Mostly curious if there are inconsistencies in the product from unit to unit and the design is actually capable of being flat or if it just isn't capable even with good examples of the unit.


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#61 Seanem44

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Posted 20 August 2019 - 08:21 AM

Thanks, Sean.  It's certainly very solid and relatively flat.  (Very nice image, btw)  

 

However, every corner is still showing elongation to some degree and that is in narrowband with less than an APS-C sized sensor.  Broadband would highlight and accentuate that even more.  I think the scope is a great value for the money, but it certainly doesn't seem to meet the product description, which is fine to me...  Mostly curious if there are inconsistencies in the product from unit to unit and the design is actually capable of being flat or if it just isn't capable even with good examples of the unit.

You bring up a good question.

 

Honestly, I think it is a matter of just not being capable to live up to the product description.  I think it lies within the helical focuser and may very well be inherent of that design.  While I do like the method, and feel it is very easy to get up an running with and I don't need to worry about my heavy imaging system pulling on a traditional focuser, I really think it is the cause of the elongation in the corners.  It is no different that any high quality lens I own for my DSLR.  They are "flat" but if used for AP, they will still have elongation.

 

That's my theory at least.



#62 AnakChan

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Posted 24 August 2019 - 04:12 AM

Anyone noticed a new limited “SpaceCat 51”? I wonder if it’s just a different gun metal colour version of the RedCat or if it’s optically corrected (aligned) version.

tainai2019_wp.jpg

E06BC078-FA13-479B-A9D1-C7A2705A89A9.jpeg

FCA063F9-E2C4-46F9-82BF-D871DFBA2A6A.png

41D5ED22-8AD4-4818-A2F4-EEEF4038C133.jpeg


Edited by AnakChan, 24 August 2019 - 04:14 AM.

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#63 25585

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Posted 24 August 2019 - 06:59 AM

Anyone noticed a new limited “SpaceCat 51”? I wonder if it’s just a different gun metal colour version of the RedCat or if it’s optically corrected (aligned) version.

tainai2019_wp.jpg

attachicon.gif E06BC078-FA13-479B-A9D1-C7A2705A89A9.jpeg

attachicon.gif FCA063F9-E2C4-46F9-82BF-D871DFBA2A6A.png

attachicon.gif 41D5ED22-8AD4-4818-A2F4-EEEF4038C133.jpeg

Seductive......

 

WO now do dedicated diagonals for the Cat scopes, I notice.



#64 AnakChan

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Posted 24 August 2019 - 08:05 AM

They have been since March :-

 

https://www.cloudyni...2019/?p=9216547



#65 Astronomy4You

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Posted 24 August 2019 - 11:45 AM

Anyone noticed a new limited “SpaceCat 51”? I wonder if it’s just a different gun metal colour version of the RedCat or if it’s optically corrected (aligned) version.

tainai2019_wp.jpg

attachicon.gif E06BC078-FA13-479B-A9D1-C7A2705A89A9.jpeg

attachicon.gif FCA063F9-E2C4-46F9-82BF-D871DFBA2A6A.png

attachicon.gif 41D5ED22-8AD4-4818-A2F4-EEEF4038C133.jpeg

 

**** that's beautiful. I wish I'd seen this before I got my White Cat a few months ago. Though I don't see it on their website. It may be a japanese only product. it looks like it has a few differences from the red and white versions.



#66 3 i Guy

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Posted 24 August 2019 - 12:06 PM

I like the Space Cat, that looks sharp! The first thing I’d do is take the lens cap to an auto-body shop and have them paint over the ridiculous cartoon logo.



#67 25585

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Posted 24 August 2019 - 12:17 PM

I like the Space Cat, that looks sharp! The first thing I’d do is take the lens cap to an auto-body shop and have them paint over the ridiculous cartoon logo.

bigshock.gif cat24.gif cat24.gif cat24.gif cat24.gif cat24.gif cat24.gif cat24.gif cat24.gif cat24.gif


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#68 Sarkikos

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Posted 27 August 2019 - 06:56 AM

It looks like the SpaceCat has a different diagonal than the RedCat.  Besides color and decals, that's the only difference I see

 

Mike



#69 AnakChan

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Posted 27 August 2019 - 11:56 AM

Didn’t see the special diagonal. However I did find more info from CyclopsOptics page. So aside from the special grey colour and the special SpaceCat logo carrying case, it seems the SpaceCat has the following :-

 

  • Extended length dual spec mounting base (Arca/Vixen)
  • Focal plane adjustment ring (O-ring)
  • Optional extra Handle Bar (pictured above)

 

Now for the first two items, it seems they are similarly offered by K-Astec/Y-Tomita’s “customed” version. In fact, looking at the SpaceCat 51 version, I have a feeling K-Astec is making the focal plane adjustment ring for William Optics.

 

I believe there’s only 1 main difference of what the SpaceCat offers vs the K-Astec/Y-Tomita’s version and that K-Astec offers 2 sizes of the focal plane adjustment ring :-

  1. M54 for the likes of the Takahashi W-Mount DX-WR ring
  2. M48 for the standard WO Copper T-Mount

I think the SpaceCat 51 offers only #2 above.

 

I’m somewhat undecided on which way to go as it’ll be nice to go with the SpaceCat 51 since it’s all William Optics (even if K-Astec may be making it for WO), however the M48 concerns me if I’ll see any vignetting. The M48 does have the advantage of taking 2” filters however.

 

The K-Astec’s offering OTOH, would be a black/white RedCat 51, and would have the larger M54 but I believe it won’t take in any filters - one would need to use a clip-in filter instead.


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#70 GraySkies

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Posted 29 August 2019 - 08:06 PM

Got some additional Images from my RedCat51 Recently (I was imaging with the EdgeHD for a few weeks).
 

http://www.emberskym.../starfest-2019/

Trifid-Widefield_WEB.jpg

Conditions were not "ideal" as I was setting up in a remote campground rather than my observatory so there were a few hiccups, lessons learned I guess.
Zenith_Edit_Final_WEB.jpg?resize=660%2C4


Edited by GraySkies, 29 August 2019 - 08:07 PM.

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#71 RobertPettengill

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Posted 04 September 2019 - 08:06 PM

What's the old saw?  "The great thing about standards is that there are so many to choose from".
 
This seems to be the best easily found explanation: https://agenaastro.c...-explained.html
 
"T/T2/"42mm T" Thread  M42x0.75  Very common in photography and astronomy. The "T thread" is identical to the T2 thread from Baader. Not the same as Pentax/screw/M42 thread, which is M42x1.0."
 
So why can't the adapter makers actually specify the pitch as well as the diameter in their product descriptions?  I have yet to see that on-line.
 
And it goes on, but what does the "T" stand for?  Telescope?  Thread?  Terse?   Tacit?
 
-- Mike


T stands for Tamron the first to use a M42 thread with a 0.75mm pitch. A T2 ring adapter is the same size but incorporates a mini adjustable swivel that allows the camera angle to be adjusted with a hex wrench.

The earlier M42 x 1.0 mm thread is often just call M42 or sometimes M42 P thread where P stands for Praktica, the first camera maker to use this thread.
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#72 Sarkikos

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Posted 05 September 2019 - 06:16 AM

Didn’t see the special diagonal. 

Sorry about the typo.  I meant "special dovetail."  foreheadslap.gif  I should be more careful posting in the morning.  I am a night owl, not a morning lark.  I am an amateur astronomer, after all.  :grin:

 

Mike


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#73 Seanem44

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Posted 05 September 2019 - 06:44 AM

Just got back from Almost Heaven 2019 and managed to put the Redcat through its paces.  Ill put my images up as I am able, but I love this little scope.

 

Is it perfectly flat?  No...  but on my copy its negligible and mitigated by the fact the areas it isn't flat are cropped either way.

 

I love the focus ring.  I didn't have to adjust focus in two nights of imaging LRGB.  Bhatinov proved focus was on point.  And at 250mm, I found I didn't even have to adjust going from LRGB to Ha/Oiii.  Pure luck maybe?  I don't know.

 

Either way...  I'm not going to argue over a little chroma, even if they advertised as "perfectly flat".  For $700, I find the scope to be a great value and if I ever want true flat at this focal length, Ill save up for a Tak.  Here's an image of M31 from this past weekend.

 

https://www.astrobin.../full/f88gd9/0/


Edited by Seanem44, 05 September 2019 - 06:50 AM.

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#74 vilchez

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Posted 11 September 2019 - 11:41 AM

I've ordered the new Space Cat 51, I'm going to use it with a ZWO 294MC Pro, does anyone know if I can use an M48 clicklock and use the camera with a 2"nose piece?

#75 waso29

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Posted 13 September 2019 - 08:09 PM

Version 2 of WO Cat51.

New improved for $31 more.

 

https://agenaastro.c...space-gray.html




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