Quote:
Originally Posted by Terry B
Dear Roger.
I agree with most of what the others have said but am just commenting on the point above. Theoretical resolution for a scope is proportional to the scopes diameter and the wavelength of the light. Focal length has nothing to do with it. Otherwise a tiny scope with a very long focal length would give hubble level resolution.
Longer wavelengths have lower resolution as well but for light this isn't terrible important (For radio astromony it is very important)
Practically of course other factors limit the resolution as you have discussed. I image a 0.78arcsec/pixel but often will bin 2x2 expecially for photometry of dim objects just to keep the file size down. FWHM for me is rarely better than 2arcsec and I live at 1100m altitude. I would be supprised if anywhere in Australia has much better. The AAO at a similar altitude to me is has similar seeing.
Cheers
Terry
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Thanks Terry for your reply, you added a few interesting points there. I'll be honest I don't understand the impact of wavelength.
Your comment regarding Hubble is one factor which got me thinking along this line. Hubble isa bit of a special case because it's outside the atmosphere, but I was thinking more along the lines of a comparison between large aperture ground based telescopes vs standard amateur telescope size, and how it is that they end up with a resolution advantage with the larger telescopes.
With your site and AAO having FWHM not better than 2, I wonder what resolution AAO image at with their larger aperture compared to your 0.78 arcsec/pixel.