Devin-M
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PhysicoRaj said:My scope is a native f/12 700mm. If I am right this mostly suits imaging the Sun, Moon, Jupiter, Saturn and some bright and narrow fov DSO's. That's all. Enough for a beginner like me if it works out.
Among the SSO's I've listed, Saturn will be the ultimate test of adequacy. I will try Saturn in the coming weeks and I can understand my scope's weaknesses better. If it doesn't work out, I will keep it for Solar and Lunar while the camera kit lenses do MW and Andromeda. I will save up for a 'calculated' scope in the future. Wallet is sealed both ways.
sophiecentaur said:With just 600mm(?) objective, the area of the DSLR sensor covered will likely be quite small. People tend to use Catadiopteric scopes like Schmidt Cassegrain to give themselves an objective focal length well in excess of 1m and small format, high res sensors - followed by all the usual tricks of course.
To get a good idea of image size, use Stellarium (free and easy to use, if you haven't yet come across it) Top right of the screen are buttons to show sizes of objects both in EP and on sensor. In the setup section, you can add your own data if there's not a ready made version of all your dimensions. Gone are the days when you had to do calculations to work out what you could see with all the combinations. Ifaik, it won't show you the sort of pixellation you will get with a coarse sensor but it's still a useful tool.
I was able to capture this after converting just the green channel to monochrome with 20 stacked 16-bit tifs (600mm f/9 1/160th sec 1000iso, shot in RAW format and histogram stretched in Adobe Lightroom). What I used was a 300mm f/4.5 nikon lens + tc-301 nikon 2x teleconverter for effective 600mm f/9 with 1000iso and 1/160th second exposures on a nikon d800 full frame sensor dslr, no tracking, 20 exposures 7 seconds apart in interval shooting mode with 3 second exposure delay after mirror flip up, image upscaled via interpolation, final conversion was to gif format to avoid jpg compression "blockiness" and hosted on separate server to avoid compression by this site's host:
https://www.speakev.com/attachments/saturn_stacked_mono_green2-gif.150147/
https://www.speakev.com/attachments/dsc_3510-2-gif.150133/
https://www.speakev.com/attachments/dsc_3510-gif.150134/
https://www.speakev.com/cdn-cgi/image/format=auto,onerror=redirect,width=1920,height=1920,fit=scale-down/https://www.speakev.com/attachments/saturn_stacked-jpg.150142/
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