Upload & Sell: Off
Thats all terrific and points well taken, but haven't we gone slightly south of where we were headed ?
My point was that I think it would be good to let more people know about Luminosity Masking.
I suppose though you have to be seeking knowledge, which is how I learned of this in the first place.
Each RGB image you open in Photoshop has many built-in alpha channels available at your command, color channels, such as Red, Green, Blue, Cyan, Yellow, Magenta,Black; saturation channels, such A, and B; and brightness channels, such as luminosity channels and lightness channel. Some people call those channels masks because they are often used as layer masks. By using simple layer math functions aka blend modes, you can come up with unlimited alpha channels for your own needs on the fly. The sad thing is that too many people just don't want to bother to learn those internal Photoshop stuff because they are falsely led to believe those 3rd-party plugins and filters will save time and money for them.
for example here are some of the most recent Annie Leibovitz's work. do you really believe everything was obtained in camera?
and more at: http://www.vogue.com/magazine/article/rihanna-unstoppable/#/magazine-gallery/rihanna-unstoppable/1