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Old 18-11-2015, 09:35 AM
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pmrid (Peter)
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Planetary Imaging: importance of image scale

I would value opinions about the importance (or otherwise) of image scale (i.e. acrseconds per pixel) in planetary imaging. Do concepts of under and over-sampling have much bearing?

I have a number of options to play with to match a CCD to a FL of 6600 (native) or 19,800 (powermate 2.5). The scope in question is my resurrected Dall-Kirkham (unmodified). It's a 317mm diameter f21 scope that I have recently brought out of mothballs and largely replaced everything bar the optics.

The choices I have without going out with credit card in hand are:
Orion Starshoot Video:
8.4x9.8 microns;
Barlowx1: 0.28 as/p FOV 2.5 x 3.3 a/min
Barlowx2.5: 0.11 as/p FOV 1 x 1.3 a/min

Lodestar
8.2x8.4 microns (752x580)
Barlowx1: 0.26 as/p FOV 2.5x3.2 a/min
Barlowx2.5: 0.1 as/p FOV 1x1.3 a/min

QHY10:
6.05x6.05 microns (3964x2712)
Barlowx1: 0.19 as/p FOV 8.5x12.4 a/min
Barlowx2.5: 0.07 as/p FOV 3.4x4.9

QHY5L-II
3.75x3.75 microns (1280x960)
Barlowx1: 0.12 as/p FOV 1.9x2.5 a/min
Barlowx2.5: 0.05 as/p FOV 0.7x1

Olympus DSLR an OMD-EM1:
3.7x3.7 microns (4608x3456)
Barlowx1: 0.11 as/p FOV 6.6x8.8 a/min
Barlowx2.5: 0.05 as/p FOV 2.6x3.5 a/min

Anyone??

Peter
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Old 18-11-2015, 09:42 AM
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Shiraz (Ray)
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this might help - universal rule of thumb and why it works. http://www.iceinspace.com.au/forum/s...d.php?t=105057

QHY5L11 direct on the DK would be a reasonably good match - no Barlow
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Old 18-11-2015, 01:55 PM
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pmrid (Peter)
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Quote:
Originally Posted by Shiraz View Post
this might help - universal rule of thumb and why it works. http://www.iceinspace.com.au/forum/s...d.php?t=105057

QHY5L11 direct on the DK would be a reasonably good match - no Barlow
Thanks Ray. Yes, it does help!
Peter
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Old 18-11-2015, 04:26 PM
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Paul Haese
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It's been a little while, so I would say aiming for something around 10m-12m give the aperture will give you something useful to work with. The faster the frame rate the better.
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