QHY8 and 6inch Archo

fo.manush · #1 23-01-2011, 12:37 AM

Hi Guys,

I have a 6Inch F8 Celestron Achromat and wish to get a QHY8 for prime focus imaging.

I just wish to know if the QHY8 will work fine with my telescope due to its CCD sensor having a relatively wide field of view.

Thanks

Tandum (Robin) · #2 23-01-2011, 12:46 AM

Qhy8 only needs a 28mm image circle so it should be ok in any 2" focuser.

fo.manush · #3 23-01-2011, 12:56 AM

Thanks for the reply Robin.

I also heard that some people with Newtonians did not have enough play in their focusers and had issues.

Could this be a problem for me? I have never had issues focusing my D90 DSLR for imaging.

Sorry for the basic questions guys...total nood here.

Tandum (Robin) · #4 23-01-2011, 01:07 AM

If it's a refractor it should be ok. You may or may not need an extension tube.

multiweb (Marc) · #5 23-01-2011, 06:42 AM

Quote:

Originally Posted by fo.manush

Hi Guys,

I have a 6Inch F8 Celestron Achromat and wish to get a QHY8 for prime focus imaging.

I just wish to know if the QHY8 will work fine with my telescope due to its CCD sensor having a relatively wide field of view.

Thanks

I use a 5" newt with a QHY8. You'l have to use a coma corrector (I use a baader MPCC) and do flat fielding to minimize vignetting.

Hagar (Doug) · #6 23-01-2011, 08:40 AM

The only problem I can see using a QHY8 with an achro is the fact that the 3 main colours all tend to have a slightly different focal point which may make your image a little out of focus or at least make the focus look a little soft. You may be able to get hold of a corrector lens which will slightly move the focal point and align all 3 colours.

fo.manush · #7 23-01-2011, 09:09 AM

Hagar,

I didn't know such a corrective lens existed. Are these freely available for purchase?

Tandum (Robin) · #8 23-01-2011, 01:51 PM

Baader make a fringe killer filter to do this. Google comes back with a few reviews on them and andrews lists the 2" fringe killer at $179.

fo.manush · #9 23-01-2011, 05:28 PM

I have a Baader Semi-Apo filter which I have loved for visual use. I think I will invest in a 2inch version for Astro Photography aswell if I go down this path. Any CA that remains after this will have to be dealt with in post processing.

I also wish to know if an equivalent Mono CCD exists out there in the same price/ performance band of the QHY8?