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For all you Schmidt-Cassegrain astro-imagers....!

Started by JohnP, Jan 07, 2008, 11:24:47

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Mac

Looks intersting, but the only problem i can see is how do you get the secondarry mirror out of the OTA, without stripping it down?

They say its very quick and easy, but i dont see how,

Especially as the secondary mirror is on the inside of the OTA?

Mac

Just done a little more digging, apart from stripping it down once it seems, the rest is pretty straigh forward,

http://starizona.com/acb/HyperStar-Conversion-Kit---Meade-10-SCT-P2614C648.aspx

mickw

So,
The Hyperstar reduces the focal length to reduce the f/ turning it into a short newt
Cables need to be dangled in front of the scope
They appear to be comparing apples with oranges - stacked digital vs. one shot film on different scope designs.
Some of you folks are churning out cracking images using the "lowly ED80" (no need to dismantle)
Sorry,
Too many clouds and just the right amount of cider is making me cranky  :evil:
Growing Old is mandatory - Growing Up is optional

Mike

This is identical to the Celestron Faststar system. The advantage of it is you get a huge aperture at a very fast speed. Cables in front of the lens won't pose a problem.
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

JohnP

Yep Mike I agree - There's a guy on UKAI forum been posting amazing images of Rosette Neb taken through his Sch-Cass with really short subs. You still do the stacking thing but you get the advantage of only having to use a fraction of the exposure time at F2 verses F10 - also don't forget you get a much wider FOV at F2 which means you can actually take a lot of images of DSO's which were otherwise much too large at F10. I think if I only had a Sch-Cass as my main imaging scope then this would be a worthwhile upgrade if you were into DSO imaging...

John

mickw

I'm surprised at that, I would have thought the advantages of large aperture would have been outweighed by the shorter focal length.
But as you say, you get a wider field of view as well.
Growing Old is mandatory - Growing Up is optional

Mike

That's the whole idea Mick - You get a large field of view, very fast speed and larger aperture. It means you can take images of Nebulae, etc. with much shorter exposure lengths, which is obviously a great advantage if you live in England and the clouds are due any minute.
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Ian

Mick, if you're handy with a diamond hole saw, you might be able to fit one to your etx  ;) :twisted:

mickw

I have a hammer drill and a file - I'm off to the shed  8)
Growing Old is mandatory - Growing Up is optional