D&B mask from image?

[asada]

Hello! I have been working on the (curve) dodge and burn technique in the fantastic video posted recently, and while I like the results, I can't help but wonder if there isn't a way to build that mask from the image rather than paint it in by hand.

It seems like if you could isolate areas of local contrast (the dark/light sides of a blemish), then put it on a black background so that only the light sides are visible, you could use that as a mask for a 'burning curve'.

I tried doing this with the high pass filter, then running a super steep curve on it to up the contrast, but the sharpening effect got in the way (I couldn't invert the image without turning it into a gaussian blur).

Any ideas? As an aside, I'm not looking for an 'easy way out' of doing time-consuming d&b, just an alternative to degrunge for photos that I can't spend several hours retouching.

[pixelzombie]

i have wondered that myself as the d/b layer tends to look like a negative of the actual image...

[camilla_k]

instead of using the dodge/burn tool you use curves and paint on the mask. see tutorial for dodge and burn in the tutorials section.

you get the same effect and some people prefer it...