questions about shg images and clouds

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highfnum
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questions about shg images and clouds

Post by highfnum » Sat Nov 12, 2016 7:00 pm

did attempt today and clouds spoiled image a bit
but it did raise some questions
1) can cloud images be removed with post processing techniques
2) people report that looking at sun thru thin clouds increases surface contrast . it looks like i got that effect on this images near one of proms. Is that true?
cloudshashg.jpg
cloudshashg.jpg (87.4 KiB) Viewed 896 times

highfnum
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Re: questions about shg images and clouds

Post by highfnum » Sat Nov 12, 2016 9:35 pm

this may be easier to see cloud effect on filament
fc2_save_2016-11-12-122926-0000ha_000.jpg
fc2_save_2016-11-12-122926-0000ha_000.jpg (111.38 KiB) Viewed 887 times

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Montana
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Re: questions about shg images and clouds

Post by Montana » Sun Nov 13, 2016 2:52 pm

Pity the clouds were right on the most interesting part, never mind at least you got to see the sun :bow :hamster:

Alexandra

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Merlin66
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Re: questions about shg images and clouds

Post by Merlin66 » Sun Nov 13, 2016 8:24 pm

John,
Good images notwithstanding the weather.
Unfortunately I don't know of any way of removing the cloud from the image.....
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Spectral Joe
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Re: questions about shg images and clouds

Post by Spectral Joe » Mon Nov 14, 2016 4:50 am

There is some hope, if the continuum near the Ha line (or whichever line you are using at the time) is not saturated. If you synthesize an image using the continuum and use this as a flat it should correct some (most) of this. It will cause the dynamic range in the affected areas to be reduced, though. Thus is the problem with any post processing, if the image data has a problem and you fix it with math there is always a price to pay.
As for enhanced contrast through clouds, it's an optical illusion related to the eye's response, not a real effect.
Observing the Sun with complex optical systems since 1966, and still haven't burned, melted or damaged anything.
Not blind yet, either!
Light pollution? I only observe the Sun, magnitude -26.74. Pollute that!

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