I've been exploring photoshop some more and I've got some questions about sharpening technique. I typically use 30/0.3/0 for percentage amount/pixel radius/threshold and it's served me well (thanks Justin!), however I'm still not sure it's ideal in some cases.
My interest was prompted when I read this informative article here:
I found it helpful as, aside from having a very basic knowledge of what USM does, I didn't have a clue what the settings really meant. Having said that, I looked at my own settings, and dug up an old thread here, and found most people prefer very low figures, but in particular a threshold value of '0'. Essentially, this means that Photoshop will apply the sharpening algorithm to all pixels where a difference is detected after creating the mask; no matter how small that difference is.
That was enlightening for me, as I had noticed on some of my images a very fine - but noticeable - saw-tooth effect on low contrast edges, such as white fuselages against the sky, or wing leading-edges against any background. I'm not talking about the USM stegosaurus you get after oversharpening, but something more subtle. Increasing the threshold did seem to help with this quite a bit.
Any techniques people want to share? Do you just avoid USM 'problem' areas and process parts of the image individually? People do get some amazing results and I thought it would be useful to exchange some tips.