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SCT corrector/flattener (not reducer)

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#1 orlyandico

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Posted 08 December 2012 - 09:41 PM

Does such a thing exist?

I'm thinking that if going after tiny planetaries, you want all the focal length you can get. But an uncorrected SCT has some pretty nasty edge-of-field issues. Is there a corrector that will fix these without reducing the FL?

Or do I just crop everything except the center?

#2 rfr66

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Posted 09 December 2012 - 09:07 AM

Have you tried looking at the new Astro Physics advanced convertible barlow? It flattens the field and increases the magnification for viewing smaller objects which seems to be what you are interested in. Here is the link. http://www.astro-phy...isual_acc.htm#1

#3 Footbag

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Posted 09 December 2012 - 09:42 AM

I would never suggest cropping as a solution, except for planetarys. That wouldnt bother me at all.

#4 rmollise

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Posted 09 December 2012 - 09:53 AM

Does such a thing exist?

I'm thinking that if going after tiny planetaries, you want all the focal length you can get. But an uncorrected SCT has some pretty nasty edge-of-field issues. Is there a corrector that will fix these without reducing the FL?

Or do I just crop everything except the center?


That's what I'd do and have done. Even more efficacious _use a camera with a smaller chip_. You don't need want a big field for small planetaries, the magnification factor of a small chip will only help, and the edge of the field will look perfect at f/10 with a small-chip CCD.






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