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Hi Fred,
I have a FLI microline 8300 on the way. This is a small chip camera so it should give the same image scale as the RCOS but at F5. So I should be able to capture galaxies etc like the RCOS did but at F5 which suits my situation.
I drive 3.5 hours to my dark site and unusually this year the weather has often been poor for imaging as compared to last year when it was often clear there.
The Planewave CDKs would be my next choice for a scope. The 17 inch would the one as it is F6.8 whereas the 12 inch is much like the RCOS 12.5 but perhaps slightly smaller micron resolution. It is also a truss which I would prefer to a tube as it is less likely to be wind affected. My site is often windy. The RCOS sat in the back of my car too many times because it was windy and therefore a waste of time. It suits somebody who lives at their dark imaging site and can spend the hours needed to accumulate the data.
Corrected Dall Kirkhams seem to be all the rage now with Peter Ceravolo making an F4.9 or F9 12 incher (basically he seems to have used the BRC250 as his inspiration for design).
But it is very expensive and F9 requires a 2nd corrector which are over US$2000 each.
Deep Sky Instruments make RC's now. They sell a 10 inch one for US$4995. These are the same optics as the RCOS astrographs for twice the price. They are F7.3 and a 14 inch version is planned.
The other scope that seems hot is the A&M 14 inch RC. Carbon fibre truss RC from the Italian manufcaturer. I have seen several stunning images from those scopes. The focuser I believe is still being perfected.
Orion Optics claim to make several versions of high end scopes but it appears none are in the hands of customers yet and seeing how ASA behaved it would be smart to let them prove themselves.
I almost bought an ASA 12 inch but flushed out the fact from the seller that it was still defective when I pressed him about sample images. Bruce Karbal has been trying to sell a "fixed up" 10 inch ASA now for a few months with apparently no takers. I guess the message that ASA scopes are not what they are marketed to be has gotten around.
There are lots of great choices around these days for high end gear.
As Mike has pointed out before 1200mm is probably the most useful focal length for overall imaging. I also like the FSQ. Long focal length imaging doesn't really suit my scene as I concluded that to get optimal results you need very long total exposure time. I like Mike cannot invest 15 hours in a single image with travelling to my site and uncertain weather in between work times. So F5 it is for now. Perhaps later a remote controlled CDK17 inch on a Paramount in a new observatory built for it. But not for a while.
I have my name down for an Astrophysics 400mm Mak Cass should Roland start producing the prototype he unveiled this year. Now that is long focal length and would suit the ML8300 camera perfectly.
Greg.
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