Smart Histogram and Darks

[poolemarkw]

What is the best sequence of events to use Darks and the Smart Histogram function for live stacking? I tried to capture and apply Darks after using Smart Histogram to set my camera exposure, gain, and brightness setting. After capturing the darks and applying the average in the "Preprocessing" form, the histogram shifted so far to the left that I couldn't get it back in the "green zones". The camera is a ASI ZWO178MC set to Raw 16.

Thanks!

Mark

[admin]

Hi,

thanks for the report - I could have sworn I'd fixed that particular issue before the 3.1 release, but it looks like either I didn't or it's back

cheers,

Robin

[poolemarkw]

Thanks. More info....the Smart Histogram set the "Brightness" control to the maximum. When the Darks were applied it shifted the whole histogram to the left, and of course there was no way to increase the brightness to move the histogram back to the right because it was already at the max. Should I have tried to change some other setting to shift the histogram back to the right?

Mark

[admin]

Hi,

try the very latest build, published last night, which should fix your issue. It turns out I had only fixed the 'brain' window for dark subtraction (which was what I remembered doing), not the bars at the top of the histogram.

cheers,

Robin

[poolemarkw]

Excellent, I'll give it a try again. Can you please clarify if this is the correct sequence of events:

1) use the Smart Histogram function to determine my optimum settings and then "Apply"
2) Capture my Darks at those settings
3) Add the resulting Dark file to the Preprocessing area
4) This will shift the histogram left. I should increase the Brightness setting to push it back into the green zones.

thanks!

Mark

[admin]

You shouldn't need or do step 4 - the green zone should move as you change the brightness so that adjusting the brightness should leave the histogram peak in the same colour zone (ie the peak and the zones should move in just the same way).

If you have followed step 1,2,3 then the peak should be in the green zone (or on the green/yellow boundary) already.

cheers,

Robin

[poolemarkw]

Excellent, thanks!