I'm getting what I can only describe as "granular clumping" in areas of otherwise smooth areas of graduating tone, e.g. sky. This effect is evident in the midtones when levels or brightness and contrast adjustments are applied. It's not dissimilar in appearance to milk separating. It's ruining the smooth tones of the original film.
Can anyone tell me why this is happening and how I can (a), cure it and (b), avoid it in future?
The image is a landscape taken on medium format, black and white IR film (Konica 750). The neg was scanned as a 48 bit RGB image on an Epson V750 scanner. The tone adjustments were applied without converting to 24bit RGB or 8 bit greyscale, to try to avoid my other continuing problem of banding in the same areas.
Thanks in advance.
It will help if you post a representative picture in order to visualize this phenomenon.