I am a photographer enthusiast. Trying to get better image quality I shoot in RAW exclusively. My main post processing software is Capture NX(2). I already have "The Photographer's Guide to Capture NX" by Jason P. Odell and have recently got his NX2 guide. It is very good source of information but for me it is not enough. I believe one cannot get the best results if one don't understand what he/she is doing. Following Jason's recommendation I ordered "Real World Color Management" by Bruce Fraser, Fred Bunting and Chris Murphy in hope it helps me to get better control over image colors. But there is (at least) one more thing I do not understand at all. I mean controlling of effect applying by "Opacity Mixer" and choosing right blending mode in particular (p. 128 of "The Photographer's Guide to Capture NX2"). I believe one of the reason I cannot understand this is I don't understand how such things as unshurp mask, noise reduction, Gaussian blur, etc... work. Couldn't anybody recommend me a book or another source of informations which describe in more details how such things as unshurp mask, noise reduction, Gaussian blur, etc... work and how they are effected by opacity and blending options. Thank you, Mikhail.