Quote:
Originally Posted by Emuhead
Appreciate the responses.
The penny dropped finally on the seeing limit, that FWHM example really helped. So in Melbourne, even if i could get down to 2 arc seconds i would only need a fairly small aperture (70mm) to max out the detail level. Then it's down to f-ratio to determine the magnification & brightness of that image (given same sub exposure time).
So anything greater than about 70mm of aperture isn't providing more detail, it's simply allowing for a brighter & more magnified image potentially.
Or have i missed a few things? Just trying to find a scope that will give me highly detailed up-close images that'll suit my mount.
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There is also the quality of the telescope to consider.
A Newt. with a small diagonal on its camera sensor
will work well but for a large frame camera - the small
spot size of say a Ritchey–Chrétien
will give smaller star sizes at the edges of the frame.
Refractors have a better contrast ratio but ones that have a high Strehl ratio
are very expensive and they don't have the light collecting power of a large Newt.
You also need to consider the application of Drizzle in stacking
and that will depend on your arc second per pixel count.
http://www.iceinspace.com.au/forum/s...d.php?t=158389
and here:
http://www.wilmslowastro.com/software/formulae.htm
cheers
Allan