What are these dark patches in my test image

Discussion of using SharpCap for Deep Sky Imaging
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Kopa
Posts: 21
Joined: Wed Jul 08, 2020 6:26 pm

What are these dark patches in my test image

#1

Post by Kopa »

M2 ST80ZWO224MCsmall.png
M2 ST80ZWO224MCsmall.png (682.51 KiB) Viewed 665 times
Hi all,

What could these dark round patches be?. Was just learning live stacking /plate solving etc in sharpcap so no flats or darks. shot through bortle8 and hazy clouds.

Any suggestions of steps to try and get rid of them in future images would be much appreciated. 2 months of no clear skies and counting.

Kind regards

Vince
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Menno555
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Re: What are these dark patches in my test image

#2

Post by Menno555 »

Hi Vince

Those look like dust particles somewhere in your set up. Somewhere on a lens or filter, then they show like this. If you see smaller, sharp edged spots, then they are on your sensor.
Two things that help the most:
1) Get a small bellow. I don't know the right English word for it. But it's the kind of small manual bellow that are used in photography to clean lenses with air. When used, you can get rid of 90% of dust particles on your lenses and/or filters.
2) Make flats. They "remove" the dark patches in your capture.

Menno
Kopa
Posts: 21
Joined: Wed Jul 08, 2020 6:26 pm

Re: What are these dark patches in my test image

#3

Post by Kopa »

Hi Menno,

Thanks for your tips on getting rid of these. I will give them a try.

kind regards

Vince
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turfpit
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Re: What are these dark patches in my test image

#4

Post by turfpit »

Vince

Menno's bellows suggestion = Rocket Blower

https://www.amazon.co.uk/KamKorda-Compr ... 717&sr=8-3

I have one.

Dave
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Menno555
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Re: What are these dark patches in my test image

#5

Post by Menno555 »

You're welcome Vince.
And yes, that what Dave is showing is what I mean. It is by far my most useful cheap piece of equipement :)

Menno
Kopa
Posts: 21
Joined: Wed Jul 08, 2020 6:26 pm

Re: What are these dark patches in my test image

#6

Post by Kopa »

Hi Menno and Dave,

Thanks for your guidance. Much appreciated.

Vince
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