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Jupiter around 0:30 11/23/12

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#1 AdirondackAstro

AdirondackAstro

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Posted 23 November 2012 - 03:45 AM

Using a Logitech C250 webcam, FireCapture, Omni XLT 150 Telescope FL 750mm F/5, 2x Barlow.
Edited in Registax 6 with drizzle.

I've tried all different settings, and I keep getting that ring around the inside of all my Jupiter images. Anyone have any idea of what could be causing this? This time around it isn't perfectly round which I'm assuming is caused by atmospheric disturbance.

Other than this ring I'm quite pleased with how this came out. No auto focuser so I focused manually.

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#2 sfugardi

sfugardi

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Posted 23 November 2012 - 08:51 AM

Mike, Usually the ring shows up after sharpening if the original data was underexposed. Next time out, try increasing the gain to give a histogram that is 2/3. If your software does not have a histogram, then just take different exposure times and process them all to optimize the condition. Manually focusing is very difficult and I find that using my reading glasses helps.

Regards,
Steve

#3 AdirondackAstro

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Posted 23 November 2012 - 03:38 PM

Thanks for the help, Steve.
I took a bunch of videos with brightness and gain up high, and in different positions. This was the best out of all of them, even the ones where the gain was up 3/4 or more I had a ring. As far as I can tell my collimation is spot on. Not sure that would cause this though. Firecapture does have a histogram, but I'm not completely sure I'm using it right. Will have to play around with it some more.

For this being my 3rd Jupiter image I'm quite happy with it, and I suppose after some more runs I'll figure out that sweet spot to get rid of the ring.






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