Correcting for artifacts during brightness/contrast changes

[Deepcore]

Hi

How does one deal with/correct/avoid artifacts(?) that come up when adjusting contrast and brightness.

Thanks

[brucet]

The only way I know how to avoid artifacts is to start with as high a quality file as possible and adjust it as little as possible.

regards

[Jean-Luc]

Hi Deepcore,
what do you mean by "artifacts" ?
As Brucet says, you must start with high quality image, if possible in RAW (16 bits). It extends the possibility in high and low light areas.

[rondo]

I usually use Levels to adjust brightness and contrast as I like the outcome. Tried Curves, but it's hard to set. Some like Histogram Adjustment. All three will give you better results than the Brightness/Contrast command with, in my experience, no artifacts.

I've only gotten artifacts when using the sharpening tools set a bit too high- whether Unsharp Mask, High Pass Sharpening etc. The appearance of sharpening is really different ways of increasing specific areas of contrast, and in this regard a low quality image or over sharpening can cause artifacts.

[hartpaul]

Hi Deepcore. What size image are you experiencing artifacts with?
All sharpening methods and various processes will produce some degradation of image and often produce artifacts.
the edge artifacts are more noticeable on small images (eg ,100 x 100 pixels) and those artifacts may not even be noticed on a 6000 x 4000 pixel image unless you are scaled right in to the pixel level.
Perhaps post a couple of examples of a before image, list the steps you do and then show the after image with the artifacts. This will give others a better idea what your problem is.