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That's great Paul. It sounds like you have great conditions. I know you are an expert in seeing from your planetary experience where its everything.
Of course guide errors are much smaller when using a short focal length. Longer focal length shows up errors much better. You see smaller guide errors with shorter focal length scopes.
I am not sure about this seeing measurement myself. FWHM seem to be a guide only. Good seeing is easily seen in the image given good focusing. I think that is one of the main criteria for measuring. FWHM values vary significantly in the same image on different stars. At least using CCDstack. So I don't know how anyone can come up with a FWHM number that is meaningful as it is more a variable than a fixed item.
Greg.
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