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For the man or woman who has everything...

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#1 MisterDan

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Posted 04 December 2020 - 07:03 PM

Search

maksutov model

on the "e" auction site.

coolnod.gif



#2 B 26354

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Posted 04 December 2020 - 07:10 PM

A link to the actual website would be helpful. grin.gif



#3 MisterDan

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Posted 04 December 2020 - 07:15 PM

-Sorry.  It's a decades-old habit of mine (e.g. not posting links to external ads/commercial sites).

 

https://www.ebay.com...koAAOSwy41fyTMG


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#4 luxo II

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Posted 04 December 2020 - 07:19 PM

"For the man or woman who has everything..."... yup, got one of those. Bought it to demonstrate basic principles to kids.

 

They were made by Jim Riffle, a retired CN'er from long ago.  Mechanical assembly is very basic - no collimation adjustments and it's not too bad at 23X, but don't expect to push it to high power. It does have moving mirror focusing - which works...


Edited by luxo II, 04 December 2020 - 07:27 PM.


#5 MisterDan

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Posted 04 December 2020 - 07:45 PM

Well, that makes a bunch of sense.  Jim Riffle => Astroworks => AstroMak.  (First Riffle/AstroMak photo I recall seeing was The Rosette Nebula, and - at that time - it dropped my jaw.)

 

Cheers.

Dan


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#6 MisterDan

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Posted 04 December 2020 - 11:01 PM

I can't let the only reference to Astro Works and the MikroScopes be that auction ad, so...

 

...enjoy:  here's the current Astro Works site:

http://www.astroworks.com/

 

Way to go, Jim.

 

Cheers.

Dan



#7 ShaulaB

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Posted 04 December 2020 - 11:02 PM

900 dollars?

#8 HoLun

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Posted 04 December 2020 - 11:47 PM

900 dollars?

thats cheap if its all manual machined.



#9 luxo II

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Posted 05 December 2020 - 12:06 AM

That would be secondhand, it’s a significant discount on the original cost. Bear in mind these were handmade as a labour of love by Jim, one by one and only a very small number made.

There were a few different versions including optional electric slewing, but no tracking. There was one SCT too.

The tripod was some sort of sintered cast powder.


Edited by luxo II, 05 December 2020 - 01:29 AM.

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#10 JohnH

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Posted 05 December 2020 - 02:22 AM

Does anyone have the optical design around?

Seen one other, but would prefer a working model, not a toy one.



I have a 12" piece of precision anneals BK-7 around that is 2.75" thick and daydream of making a series of SolidCat Maksutovs made with the front AND back surfaces having the two mirrors on them.

#11 luxo II

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Posted 05 December 2020 - 03:25 AM

These are not solid. They’re Gregory-Maksutovs at f/12. I think the optics were left-overs from production of a commercial product.

I’m not sure a solid mak is possible as both surfaces of the corrector are required to produce the correction for SA. A solid SCT is possible because the correction of the wavefront occurs at a single (front) surface.

 

MKV would know for sure.


Edited by luxo II, 05 December 2020 - 03:48 AM.


#12 JohnH

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Posted 05 December 2020 - 11:38 AM

These are not solid. They’re Gregory-Maksutovs at f/12. I think the optics were left-overs from production of a commercial product.
I’m not sure a solid mak is possible as both surfaces of the corrector are required to produce the correction for SA. A solid SCT is possible because the correction of the wavefront occurs at a single (front) surface.

MKV would know for sure.



The SCT has 3rd order curves to correct aberrations. Usually the Gregory design achieves correction by deepening the R1 curve with a star lap.

#13 JohnH

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Posted 05 December 2020 - 01:15 PM

At the other end is this beast:

https://astromart.co...assegren-ota-16
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#14 luxo II

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Posted 05 December 2020 - 04:56 PM

Ya... and APM had a 20” not so long ago... I’ll have to retire to the mountains first LOL

Edited by luxo II, 05 December 2020 - 05:21 PM.


#15 Jaimo!

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Posted 06 December 2020 - 01:00 AM

900 dollars?

You could almost buy a real one...


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#16 B 26354

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Posted 06 December 2020 - 02:21 AM

You could almost buy a real one...

Art for art's sake.




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