FR/Flattener or Corrector or both????

[Nico13 (Ken)]

Hi all,
I'm wanting to improve my old 8"Meade SCT non ACF to try a bit of imaging, no fancy stuff mind you but just want to give it the best chance I can.

I will be using my standard Pentax K5 SLR as the image source and want to know what is my best combination of Focal reducer flattener or coma corrector or can you run both? Does a flattener help with coma at all?

I'm tending towards the Meade f/6.3 focal reudcer/flattener or similar for a start and would like others opinions before I spend the dollars.

Thanks

Ken.

[Poita (Peter)]

Originally Posted by Nico13

Hi all,
I'm wanting to improve my old 8"Meade SCT non ACF to try a bit of imaging, no fancy stuff mind you but just want to give it the best chance I can.

I will be using my standard Pentax K5 SLR as the image source and want to know what is my best combination of Focal reducer flattener or coma corrector or can you run both? Does a flattener help with coma at all?

I'm tending towards the Meade f/6.3 focal reudcer/flattener or similar for a start and would like others opinions before I spend the dollars.

Thanks

Ken.

The Meade and Celestron 6.3 are basically the same unit. You are welcome to borrow mine if you want to see if it will work for you.

[Nico13 (Ken)]

Originally Posted by Poita

The Meade and Celestron 6.3 are basically the same unit. You are welcome to borrow mine if you want to see if it will work for you.

Thanks Peter, that's a most generous offer but at this stage I won't take it up as you would likely be without it for a number of weeks while I fitted in testing in between rotating shift and some clear nights.

I would be happy to purchase on others experience and recommendations so I'll wait to see if I get some more replies to this post for a bit.

Thanks again

Ken

[Poita (Peter)]

The only scope that I have that it fits, is currently on loan to a bloke in Sydney anyway, so I won't miss it.

It is pretty much your only choice in that price range, TS make a seriously nice one but it is 5 times the money.

It works well, but I haven't tried it on a DSLR. PM me your address and I cn send it to you in about a week, they really are something you want to try before you buy.

For an APS sized sensor, with an 8" scope, the field won't be truly flat, and you will get some vignetting. You would get better results using a spacer to get an effective reduction to F8 or so, at 6.3 you will get a compromise.
The flattest result I can get is using the F6.3 Celestron correct/reducter, an SCT to 2-inch adapter and then an MPCC. (Yes I know the MPCC is designed for Newts, but this gave the best results)

There is nothing really available that does a better job that I am aware of (and is affordable), and I've tried a few.