Quote:
Originally Posted by Amaranthus
I was creating a FOV calculator in Excel for my equipment, and this included working out the resolution (arcsec/pixel) for my Neximage 5 planetary cam.
I worked out the following for my C8:
FL = 2032 mm
Chip width = 5.7 mm
Pixel size = 2.2. microns
TFOV = 9.6 arcmin
Resolution = 0.22 arcsec/pixel
If I add my 2.5 PowerMate (which I often do to get a larger planetary image, despite the hassle of holding it in the centre of the FOV), I get:
TFOV = 3.9 arcmin
Resolution = 0.09 arcsec/pixel
Now, the Dawes resolution limit for my C8 (203 mm aperture) is 0.57 arcsec. This tells me that it seems to be pointless ever using the PowerMate for planetary imaging on this scope, because the imager's per-pixel resolution even at f/10 is smaller than my telescope's resolving power. In fact, I may as well leave my f/6.3 FR in, because the resolution per pixel in that case is still 0.35 arcsec/pixel!
Is this correct, or have I overlooked something?  |
as Ken says, FNo = 5x pixel size in microns - you are right, you don't need a Barlow with that chip/scope combo.
http://www.iceinspace.com.au/forum/s...d.php?t=105057