Live stack histogram horizonal zoom

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PeterAB
Posts: 34
Joined: Sat May 21, 2022 4:12 am

Live stack histogram horizonal zoom

#1

Post by PeterAB »

Hi,

I adjust live stack colors, brightness and contrast with the histogram horizonal and vertical sliders. I work with the "zoom" and "log" boxes checked.

When my total integrated exposures go longer, the histogram peak goes narrow. So much that it is difficult to see and control movement of the sliders. The narrow histogram may also be more pronounced with my new Poseidon-C vs my asi294mc. I not completely sure about the camera's effect on the histogram yet. Many changes with the new camera.

Is there a way to increase the effective zoom that the "zoom" check box delivers? I'm using a laptop with a 1920x1280 display.

Thanks,

Peter
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Re: Live stack histogram horizonal zoom

#2

Post by admin »

Hi Peter,

there's no way currently to change the zoom level, but if you are using the horizontal 'log' option then ensuring that the histogram peak is as far to the left as possible (subject to not black clipping) will help - reducint the offset/brightness/black level control to the minimum value compatible with no black clipping will help. This works because the log scaling (which is no longer quite logarithmic, but close) gives a stronger effective zoom the further towards the black level you are.

I have some changes coming soon(ish) that will allow background subtraction in live stacking to move the peaks further left, which I think should help in this sort of situation - it will also help make colour balancing easier. If that doesn't help enough then more/variable scaling might have to happen.

cheers,

Robin
PeterAB
Posts: 34
Joined: Sat May 21, 2022 4:12 am

Re: Live stack histogram horizonal zoom

#3

Post by PeterAB »

Hi Robin,

Thanks, that makes sense. I have some room to decrease black level offset with without clipping.

Peter
PeterAB
Posts: 34
Joined: Sat May 21, 2022 4:12 am

Re: Live stack histogram horizonal zoom

#4

Post by PeterAB »

Hi Robin,

The new live stack background subtraction widened my histogram peaks and moved them left. The peak is nice and wide and easy to work with. No issues, it just worked. I used the automatic function.

Thanks, Peter
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