Live Stack Save Issue

Discussions of Electronically Assisted Astronomy using the Live Stacking feature.
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DykesC
Posts: 3
Joined: Thu Apr 28, 2022 8:35 am

Live Stack Save Issue

#1

Post by DykesC »

New to SharpCap. After live stacking several frames I performed a histogram stretch and color adjustment. I then saved the final image using both "with adjustments" and "as seen on screen". The final png images don't appear to have the color adjustment applied to the entire image. See example below. Any help will be appreciated. I have RAW16 selected and I am using an Atik Infinity camera. Running Windows 10.
Stack_71frames_1818s.png
Stack_71frames_1818s.png (966.42 KiB) Viewed 1690 times
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admin
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Re: Live Stack Save Issue

#2

Post by admin »

Hi,

I think what has happened here is that sometime during the stack, the telescope has shifted position somewhat (or maybe drifting slowly off target). The darker area you are seeing in the bottom right is the portion of the image that has now shifted out of view of the camera, so it is no longer receiving image data in each new frame. The live stacking has continued to align each image, so the effect of the telescope shift is only seen in this darker area of the stacked image.

cheers,

Robin
DykesC
Posts: 3
Joined: Thu Apr 28, 2022 8:35 am

Re: Live Stack Save Issue

#3

Post by DykesC »

admin wrote: Thu Apr 28, 2022 1:46 pm Hi,

I think what has happened here is that sometime during the stack, the telescope has shifted position somewhat (or maybe drifting slowly off target). The darker area you are seeing in the bottom right is the portion of the image that has now shifted out of view of the camera, so it is no longer receiving image data in each new frame. The live stacking has continued to align each image, so the effect of the telescope shift is only seen in this darker area of the stacked image.

cheers,

Robin
Just to make sure we are seeing the same thing, please note that there is a rather large (wide) area on the right side separated from the rest of the image by a perfectly vertical and well defined transition. Likewise on the bottom a somewhat smaller area is separated from the rest of the image by a perfectly horizontal transition. If live stacking is paused and then resumed after a few minutes have passed would that account for what I am seeing? Thanks for replying Robin. Great piece of software.
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Re: Live Stack Save Issue

#4

Post by admin »

Hi,

yes, that was the image artifact that I was talking about :)

A pause and then resume of the stack would quite possibly be the cause - if you have some drift of the mount tracking then the drift will accumulate while paused, meaning that when you resume the camera image may have moved quite a bit from the original view.

cheers,

Robin
DykesC
Posts: 3
Joined: Thu Apr 28, 2022 8:35 am

Re: Live Stack Save Issue

#5

Post by DykesC »

admin wrote: Thu Apr 28, 2022 3:51 pm Hi,

yes, that was the image artifact that I was talking about :)

A pause and then resume of the stack would quite possibly be the cause - if you have some drift of the mount tracking then the drift will accumulate while paused, meaning that when you resume the camera image may have moved quite a bit from the original view.

cheers,

Robin
I believe that explains it. Many thanks!
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