Quote:
Originally Posted by VintageKell
And on another tack .... there are web links on the subject of banding ... some deal with gradient banding (including colours).
One here
Another one here
And especially Here
Finally: This last website link seems to have cracked it ..... I won't try to explain as its illustrated.
Some food for thought ....  |
The abovementioned websites deal with several different forms of colour banding that can occur, but I don't think beutelwolf's problem image is the result of inadequate colour representation.
Nor do I think the scan problem the last website describes is the cause because it deals with a straight band whereas the colour banding in beutelwolf's image are circular.
Instead I believe the problem is caused by a phenomenon known as Newton's rings which can occur when light is reflected between a spherical surface (your scanner's lens assembly) and an adjacent flat surface (the glass plate on which your image lies).
If you take a look at the wikipedia article on Newton's rings
here the second image on the page looks a lot like the pattern which is visible in the red and blue channel of the image.
Still looking for a decent way to get rid of it more quickly though.