Levels Adjustment And Shadows

[smoke665]

Think I'm right in this, but will the use of the "Levels" adjustment sliders in PS cause a posterization effect in deep shadows?

 

[KmH]

Maybe.
Putting Ps in 16-bit mode when editing 8-bit color depth images goes a long way to preventing posterization.

Image Posterization

 

[smoke665]

Maybe.
Putting Ps in 16-bit mode when editing 8-bit color depth images goes a long way to preventing posterization.

Image Posterization

I found this on Adobe, help site, which somewhat explains what I'm going through. I'm editing in 16 bit, but if I remember correctly some editing functions in PS would convert your file to 8 bit, not sure if the new one does but I'm seeing this effect on heavily edited files.

"The importance of 16-bits precision lies in the degradation that can be produced by stretching the tones so much that you can perceive 'posterization', that is visible differences between contiguous and nearly monochrome areas and gradients like skies or stage backgrounds. The eye can perceive the boundaries between those areas if their digital values are farther apart."