C11 Hyperstar is it worth it?

[Rocket Pooch]

Hi,

I have an opportunity to get one of these at a reasonable price, I wondered if the C11 users (Mark and Robert) have any comments about this setup, it will be used with the QSI not a DSLR.

Chris

[MarkS]

C11 is a very versatile scope.  Brilliant for planetary and Hyperstar but not so good for imaging in its native configuration.  I can't comment on the hyperstar but all images I've seen from it (once properly collimated) have pin sharp stars from corner to corner.  I think there are issues with some filters not working well at F/2 (colour shifts?) - Robert can give more info I'm sure.

I also think it is best to buy a Fastar compatible C11 if you want to use Hyperstar - again Robert can comment.

The only negative is that in its native configuration 2800mm at F/10 or with a reducer (e.g. 2240mm at F/8  or  1760mm at F/6.3) it is a very slow scope for imaging and has distorted stars at the edges.  The Teleskop Service corrector (TSSCKorr)claims to deliver a flat undistorted field and I'm hoping this is true once my teething problems are sorted out.

Mark

[RobertM]

I would agree with Mark, but I can only really comment on the Hyperstar configuration:

1) Produces very good images with incredible resolution.  For instance I felt that the 450D could have had more pixels.
2) Being able to see the Witches Broom crystal clear in RGB with a single 60 second image - you just won't believe what it will pull in.
3) There are absolutely horrendous gradients with Canon DSLRs due to the off-center rectangular opening - that's why I intend to use a OSC for which images flat out ok.
4) Collimation can be a bit hit and miss due to the less than ideal adjustment arrangements.  Live view or near live view of a defocused centered star is the easiest way.  It can be done with other programs but I've found that problematic and tedious.
5) Any impingement of the camera into the optical path will produce artifacts such as spikes.

Narrow band is an unfulfilled area still to reach it's full potential.

It would be best if you could find someone using the QSI500 series with a C11 and ask them.

The Fastar conversion kit is not that expensive and very easy to fit but I would echo Marks comments and get one of the older versions with it already fitted if you can (or even better an Edge OTA).  I got my HS direct from Starizona as it worked out quite a bit cheaper.

It may look a bit bleak bit I wouldn't want you to get into HS imaging without knowing all the nitty gritty.  The system is capable of tremendous images in the right hands but you won't see many using it to it's true potential.  I can certainly give you a Demo anytime we have clear skies (maybe DSC this w/e).

Hope that helps
Robert