Setting black level

[Howardk]

I know that i should set the black level or offset so that the histogram is just to the right of the vertical axis with no pixels being clipped

My question is when i look at my histogram the red channel is always left of the luminance and green and blue lines

So do i adjust the black level to bring the red line or the luminance line just to the right of the vertical axis?

If it’s the red line then the luminance is quite far from the vertical axis and if it’s the luminance line then the red is being clipped being too far to the left

[admin]

Hi,

I wonder if you have adjusted the colour balance controls in the camera controls on the right to bring down the brightness of the red channel? That's a common reason why one histogram channel might be different to the others (usually, with no adjustment to colour balance, you would expect to see all the same for dark frames and red/green a bit higher than blue for light frames due to the typical yellowish colour of light pollution).

I would normally recommend leaving all the colour balance controls on the right at their 'neutral' settings and never changing them - fix colour balance in post-processing (ie in live stacking, planetary live stacking or when processing/stacking frames after capture). Keeping clear of the camera colour balance controls simplifies imaging as you don't have to worry if they are the same between dark frame and light frame capture (they should be!).

In general though, make sure that *all* colour channels are clear of the left hand side - one might be only just clear with the others further clear, that's fine. The goal is to avoid having any pixels that are pure black

cheers,

Robin

[Howardk]

Robin
My camera in raw16 doesn’t show colour balance controls

I adjust them from the live stacking histogram only

[admin]

Hi,

OK, next idea - was it not quite fully dark? You can get a dominant blue channel in the background in the last stages of twilight - basically the remains of the blueness of the sky are brighter than any light pollution still.

cheers,

Robin