44 replies to this topic

[RichA]

http://r2.astro-fore...ksutov-150-1800

 

http://r2.astro-fore...hotomak-152-912

 

[dweller25]

6” F/12 v 6” F/6  - there is bound to be a difference

[treadmarks]

Every time I look at the star image in my Orion Mak, I am stunned by how perfect it looks. For this reason I am hesitant to trade it off even though the spotting scope configuration is annoying.

[RichA]

The best Mak on the site was a TEC 6 inch that frankly tested better than many of the high-end refractors, a peerless instrument.  

[Dave Novoselsky]

Wonder how the AP Mak would have tested out? I know Marj auctioned one off last year on AM.  Can’t recall how much it sold for,think it was a right arm and part of the left as well.

[luxo II]

I've always said the Synta maks are a bargain, with optics that are consistently good to perfect, as in that example.

[vahe]

The best Mak on the site was a TEC 6 inch that frankly tested better than many of the high-end refractors, a peerless instrument.  

 

The design difference between TEC Maks and the Chinese competition is that all TEC Maks 10" and smaller are spherical Remakes with separate secondaries, Chinese 150 and 180's are Gregory variant with spot secondary and aspheric primary.

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Vahe

[RichA]

The design difference between TEC Maks and the Chinese competition is that all TEC Maks 10" and smaller are spherical Remakes with separate secondaries, Chinese 150 and 180's are Gregory variant with spot secondary and aspheric primary.

.

Vahe

There is also an article on the site dealing with Roland C's 10 inch Maks in which the author states there are machines which can now turn out 1/20th wave spherical opticals automatically.   So a Gregorian may be a relatively easy thing to make these days.  Though I don't know if such machines can do it with large optics.

[alnitak22]

My Synta 6” f/12 Mak is sharp as a tack and was a steal at 700 bucks when I got it 3 years ago.

[luxo II]

Wonder how the AP Mak would have tested out? 

Wonder no more there are plenty of images from these scopes on Astrobin.

https://app.astrobin...arollo?i=xricwg

https://app.astrobin...arollo?i=n5nn5a

https://app.astrobin...arollo?i=tdydg4

https://app.astrobin...arollo?i=o7xmgp

Edited by luxo II, 17 February 2025 - 12:22 AM.

[kgb]

Wonder no more there are plenty of images from these scopes on Astrobin.
https://app.astrobin...arollo?i=xricwg
https://app.astrobin...arollo?i=n5nn5a
https://app.astrobin...arollo?i=tdydg4
https://app.astrobin...arollo?i=o7xmgp

I only see four images total. Are you able to uncover more? Wasn’t able to query anything additional on AB.

[fred1871]

Gregory Maks (which are not 'Gregorians' ) do not scale up well to larger apertures.

Hence the 1988 book by Rutten and van Venrooij with its discussions of the 'Rumak' style of Mak with a separate secondary.

And plenty of literature since on non-Gregory designs.

[quilty]

6” F/12 v 6” F/6  - there is bound to be a difference

Just compare CO

[davidc135]

The f/6 is an imaging specialist and succeeds very well at that according to the website.

 

David

[quilty]

Yes. And therefore such a comarison is pointless.

Who's better a marathon man or a 100m sprinter? Quite easy to tell. The marathon man does better at long distances while the sprinter wins at short term.

[Asbytec]

I've always said the Synta maks are a bargain, with optics that are consistently good to perfect, as in that example.

They are. I dared several times to suggest they may be as good as Intes standard models. 

[quilty]

I'm not sure yet if the golden ones are as good as the recent specimen

[vahe]

There is also an article on the site dealing with Roland C's 10 inch Maks in which the author states there are machines which can now turn out 1/20th wave spherical opticals automatically.   So a Gregorian may be a relatively easy thing to make these days.  Though I don't know if such machines can do it with large optics.

Regarding Astro-Physics 10” Mak, Roland explains;

.

"The 10” Mak-Cass was a particular design, (aspheric Gregory) that is not easy to produce. It requires complex aspheric on the primary mirror. Aspherics are hard to make smooth and perfect, and in this case it took me almost 1 year to make just a small number of these scopes, Each mirror took about 1 week of painstaking hand work.
After that experience, I took a long break from making that sort of optic again. By contrast, and all-sperical Simak or Rumak design, which was made by TEC for a number of years, is simple and straight forward.
Nevertheless, if I ever make any more Maks, they will have all-spherical design, because the aspheric design is not practical."

.

Strangely when Roland decided to do the second run of his 10” Mak, despite his promise never to do aspheric Gregory, he did it again !!!!!!

.

As for Gregorian Maks, in these variants the meniscus position is reversed and is moved outside of primary focus point. Negatives these are longer and slower OTA’s, positives are straight-up images. The only commercially produced Gregorian that I am familiar with was offered by TEC some thirty years ago (100mm F15 @ $500.00), it was intended for terrestrial use.

.

Vahe

[SandyHouTex]

Wonder how the AP Mak would have tested out? I know Marj auctioned one off last year on AM.  Can’t recall how much it sold for,think it was a right arm and part of the left as well.

Like $65,000?  I can't find it on the site, and I'm a member, but it was outrageous.

Edited by SandyHouTex, 17 February 2025 - 06:41 PM.

[Dave Novoselsky]

Yep, but who are we to toss bricks.  Look at how much the ‘basic’ AP go for on the secondary market.  And none of that is Roland or Marj’s fault, they could but don’t charge a bunch more.

[CHASLX200]

Yep, but who are we to toss bricks.  Look at how much the ‘basic’ AP go for on the secondary market.  And none of that is Roland or Marj’s fault, they could but don’t charge a bunch more.

Reason i never bought a AP scope used but one before the prices went nuts when i got a 6" F/9 Blue tube for 1500 smacks in 1998.

[luxo II]

Can’t recall how much it sold for

$68,300 https://www.cloudyni...mak-cass/page-4

[SandyHouTex]

$68,300 https://www.cloudyni...mak-cass/page-4

For a 10 inch Mak.  Unbelievable.

[luxo II]

It was a 12”. The optics were Russian but retouched by AP and the OTA was built by AP. 
just a bit too big and heavy for portable use.

[manfromplanetx]

Every time I look at the star image in my Orion Mak, I am stunned by how perfect it looks. For this reason I am hesitant to trade it off even though the spotting scope configuration is annoying.

I have a 180mm Orion Mak that I havent even had on a mount yet... hopefully someday soon!

 

MPX