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I'd second Rally there.
Pixel size is more of an issue for longer focal length scopes.
You can get away with anything with an F5.5 90mm scope. Those sorts of scopes are not particularly affected by seeing as they are not resolving fine detail to that extent. That fine detail kicks in with longer focal lengths.
Look at the numerous stunning images of FSQ/STL11 or 16803 cameras with 9 micron pixels. 9 micron pixels seems to work on any scope by the way so it would seem to be the sweet spot for astronomical imaging where the performance characteristics of the chips, the optics, the available seeing all seem to meet at a nice compromise.
Basically, I think the wider field the scope the less important pixel size matching becomes.
It becomes quite an issue at about 1200mm focal length and beyond and vital at 3 metres. You will see a slightly more alive and vital image using a smaller pixelled camera at around the 1200mm focal length versus a 9 micron pixelled camera. But it would require night of stable atmospheric conditions.
Other considerations are then more important at the short focal length.
Cooling,Noise levels, sensitivity, autoguiding solutions, cost. Bascially high cooling solves most problems with CCDs. Noise, artifacts, cosmetic blemishes like lines.
I agree, one shot colour is your best bet. Simpler, easier and you get nice results (not the 100% best you can achieve but very good regardless).
SBIG One shot colour ST8300's come up on Astromart every now and then. Often around the $1350 band. Add in $250+ for shipping and $150 for GST and you are not far off the cost you had in mind.
FLI, QSI, SBIG, Apogee are the big name brands that all make great cameras.
Atik, QHY are the 2nd tier. Starlight Express is somewhere in there as well perhaps first tier perhaps in between.
For absolute performance of the camera itself FLI still is around top spot with its most powerful cooling, high quality everything but lacks accessories like autoguiding setups. Same with Apogee, great electronics, great performance, bigger and bulkier and a quirky slow cooling system.
QSI have integrated all these features nicely and have caught up a lot with FLI in the cooling, electronics etc so that probably makes them near the top now as they are nicely integrated with filter wheel and autoguiding solutions. SBIG is much the same with their latest round of cameras offering nicely integrated cameras. Their latest offerings of the STT range would appear on paper to be a good attempt at regaining the crown, yet to be reviewed but I suspect they may have taken the crown back.
Anyway that is future for you as all those brands are in the $4000- $8000 band by the time you kit it all up to be a complete system.
Expensive eh?
So the suggestion of the one shot colour makes more sense now or hang around astromart.com for 2nd hand bargains or some appear in the classifieds on this site from time to time.
Brendan is right, you probably don't want to use a chip smaller than the KAF8300 (its something like 19 x 12mm or so). If you do you will get a magnification factor and you'll end up with images that are pushing the scope beyond its ability, too zoomed in for the aperture of your scope. You lose lovely widefield factor.
A formula is 5.5 to 9 micron pixels, with the largest chip you can afford to obtain the widest most detailed images you can.
90mm F5.5 is potentially a fabulous widefield scope.
Greg.
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