Night Shots - C&C - Question about colour "banding"

[kirbym2]

Hi All,

Looking for some feedback here, but also wondering why these shots show up so poorly online? I'm seeing bands of colour leading from the horizon up. Anything I can do to correct this?

1

DSC_6929 by McFlickr81, on Flickr
2

DSC_6939 by McFlickr81, on Flickr

Thanks!

 

[MissCream]

They are so dark I can't see anything....

 

[KmH]

It's because JPRG only has an 8-bit color depth.

8-bits, 11111111, can only represent 256 gradations of tone (colors). The gradients in the sky likely have 5 times that many colors. So the transitions to the various colors can't be done smoothly with only 256 possibilities, and are stepped (banding).

The cure is to add some image noise to the image file. With Photoshop you can select just the sky and only add the noise there.

Raw is either 12-bit or 14-bit. 12-bit can render 4096 colors, and 14-bit can render 16,384 colors. Raw filoes get converted to 16-bit, but the additional bits onlyn add space for the parametric line commands, not additional image data.