Yes a square filter bottom seems like the clear explanation doesn't it, but no.... it was a circ polariser and circ ND.

Actually I did - other thoughts?

Thanks for your help guys - correction OFF seems to have worked.

However I have another issue.... I took this shot of The Nobbies (I know, great name!!) Phillip Island, Victoria, Aust this week using my K30 with my 15mm f4 and a B+W ND10 filter on the lens and got this strange line across the bottom.

Exposure is 113 secs, f22. I have used this filter a few times with no such issue. Is it electro magnetic interference of some type? I was using the stopwatch on my iphone nearby. Could this have been the cause? Note there is also some colour costing in that area.

Any thoughts or help would be most appreciated. Thanks.

Hmmm, yes I think it's on Auto. Is that the cause?

Daniel. Any luck solving this? I have had my K30 for a month and am very frustrated by the banding in clear blue skies. It looks like yours. It's only in jpegs. If I look at the raw version of the same it's not there. Can you alter the amount of JPeg compression? I am shooting on the highest quality setting as it is..... Thanks.