Am I doing DBE correctly?

[johndias]

I struggle with DBE, it takes me a very long time to get all of the sample points right and then I'm never really happy with the results.

For example, in this image, I had to boost the tolerance very high (1.8) to get coverage where I needed it.  In the end, I get this mottled kind of result.  I tried reducing the samples per row and increasing the sample size but it still gives me the patched background.

Are my images just garbage with no way to fix?  Too much LP gradient to deal with?

[stevek]

Firstly, too many samples.  I just use 6 per row on nearly all images.  Too many just confuses the algorithm.  Remember it is large scale gradient structure you need to be looking for and that does not need many samples at all.  Indeed, some folks just use 4 on the whole image, in the corners.

Quite right on some images that you have to lift the tolerance.  Normally I am at about 1.2 but sometimes have to go up to 2 and even higher depending on gradients, light pollution etc.
Are you restretching after DBE with the STF tool?  Since the background gradient will be less after DBE then STF stretches more aggressively revealing more "mess".  Save your STF before DBE then reapply the same STF after DBE and it will be much better.
Steve

[johndias]

Thanks, I did reduce the samples to 6.  Much easier to work with anyway. 

So, I tried saving the STF and applying but the stretch comes out not so good.  But, I'm not worried because I did a preview in HT and it looks much better and I think I can work with this.

Thanks Steve!