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Greg, I have to say that at the moment I'm not too keen on spending more money for a TEC flattener and a new camera, and a new mounting system. I still have so much to learn. It does seem I could keep things a lot more basic by staying with the KAF8300 for now. I guess I'm confused about the point re resolution. I've been reading Ron Wodowski's book which seems to say that 2-3 arcsec/pixel is ideal if seeing won't support greater resolution. So, I guess my question is if I'm using full resolution with a KAF8300 (1.14arcsec) and seeing is marginal am I actually worse off than using a camera with larger pixels, or just not getting the resolution I could if seeing were ideal?
It comes down to sampling theory which states you need at least 2X to get a decent sample. In practice that goes to 3. So if you get 3 arc second seeing which is common then around 1 arc/second per pixel then is ideal.
Ron has a calculator that works out the various camera/scope combos and calculates the arcsec/pixel.
But around .66 to 1 is good based on the above. The longer the focal length then will mean your 5.4micron KAF8300 pixels are oversampling too much and unless you get excellent seeing where it brings you back closer to those numbers you will find fuzzier images than a 9 micron camera. I have seen this in action with my CDK17 where my FLI ML8300 gave quite poor images of M83 whereas same scope, my Proline 16803 gave quite noticeable superior details and sharpness. I did this several times so it was not just seeing conditions on the night.
I think you will find examining posted KAF8300 images that the ones that seem the best or seem to have a sparkle are taken with scopes under 1500mm focal length and the shorter the better.
Look at Martin Pughs recent image with a lens and 8300 - it was very vibrant - more so than if he had've used a 9 micron camera.
On the other hand look at long focal length 8300 images. Unless they were taken in Namibia or somewhere with great seeing they seem "stretched" like expecting too much from it.
Greg.
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