D60 problem w/ smooth gray background

[rfogt]

I have recently begun using my D60 to photograph small objects on the gray paper tabletop sweep. The lighting is one overhead softbox, adjusted to give a smooth gradation from light gray foreground to a dark gray background. The problem is that the camera doesn't render this as a continuous tone, but rather with a kind of banding. I'd describe it as being a very subtle posterization effect, not very pronounced, but noticeable. (Not just in the print, but on the monitor as well.)

At first I thought it might be a result of the jpeg compression's inability to deal with this type of background, so I tried shooting a RAW file, then converting to TIFF, with the same results. I sent a file to a friend of mine, who opened it on his machine and saw the same phenomenon. He then set up a similar situation in his studio, and got the same results from his D60.

When the light is adjusted so the fall-off isn't as abrupt, the camera seems to deal with it much more successfully. Is this a normal shortcoming? Has anyone else experienced this? Am I just overlooking something obvious? Any help will most certainly be appreciated, as I'm out of ideas.

Bob

[lziering]

I just sold my D60 to buy a 10D and I don't remember if the D60 can output at 16bit. If so, you should use that because it will allow a wider tonal range. Not sure what else to suggest.

[john_houghton]

Try outputting the tiff file in 16-bit mode and applying a small amount of noise with Photoshop - say 1% Gaussian. The dither should break up any banding. It's a technique I have used to avoid similar problems when generating fake skies. (I realise that adding noise to a D60 image goes against the grain!).

John

[AJSJones]

John, I guess you're suggesting adding some "grain" rather than going against it, but subtle noise is less objectionable than subtle banding (and to the digital-bashers, better than no noise!)
Andy