Strange Digital Banding in Skies - Is that normal?

[lad_lueck]

<p>Good God, what alot of typing, without actually telling the OP what to do!<br>

1. Expose the image as bright as possible, without blowing the sky. (This gives you a greater effective bit depth, making the areas of banding/posterization physically smaller when viewed). Then reduce 'exposure' levels in your RAW converter, or PS.<br>

2. Use PS's Add Noise (Gaussian, Monochromatic) tool to add a tiny amount of noise to the sky. This will eliminate the banding very effectively, without adding much/any visible grain that ruins the image. If you want to get fancy, view the individual R or G or B channels, and only add noise to the one(s) that band the worst.</p>

[tom_mann1]

<p>Lad, you gave excellent advice if the major problem was banding, and I also agree with you that there has been some extraordinarily irrelevant suggestions and info given in this thread. </p>

<p>However, from my POV, the reason for "all the typing" is that banding appears to be secondary problem to JPG artifacts, as can be seen in the version of her image that I enhanced to make the artifacts more visible. The problem is that we don't know if the OP even has a clue how and where the JPG artifacts got injected into the chain of processing, and I am trying to get to the bottom of this question by giving her an approach which will resolve this.</p>

<p>Tom M</p>

[vanessa_b2]

<p>Thanks for all the latest contributions to this thread.</p>

<p>Ann, my camera specs are the same as yours, except I have lossless compression of file (the other one is compression). When I took this picture months ago, I didn't have Nikon View Nx2, but since then, I've used it to upload my pictures. The thing that troubles me is that it only happens sometimes. This inconsistency makes the problem difficult to identify. By the way I didn't use any filters or special tricks when I took the picture.</p>

<p>Tom, thanks again for your determination to understand this problem! I'll try and attach the square. I saved it as optimal quality (12) in Photoshop and baseline optimised. The picture I attached originally was edited down so that Photonet editor would accept it.</p>

<p>I don't recall doing anything to the image whatsoever (and this has happened to other images) and am wondering if it was a clash in the different colour spaces.</p>

<p> </p><div></div>

[ann_overland]

<p>Do you have any original files with this problem? You should be able to see this in ViewNX2. (Before any kind of editing is done to the files). If you can see it in ViewNX2, than it would not be your post processing software causing the problem.</p>

[vanessa_b2]

<p>Hi Ann<br>

I will take a closer look at pictures in View NX2, thanks! I only started using it relatively recently.</p>

[derek_simpson]

<p>RE jpg - yes compression will make banding worse - but I have a batch of CR2 raw files from a Canon 1DsII showing banding straight from camera - only picked it up after processing as 16bit but backtracking showed it there on the ingest file. Quite a few similarly affected from agorgeous day in verona - so not something I can re-shoot. It seems no matter how careful the processing this is - like moire and sharpening - one of the severeral downsides of digital. All progress in photo technology is about convenience - smaller, lighter more versatile equipment - and then you go to an exhibition of pictures from 1900 and realise how much better they were.</p>