With the Adjustment Brush, I paint over the area I want to affect. Why would I add the pins to different parts of the image?
I want to paint increased saturation over parts of my image. How do I paint increased saturation without affecting the Exposure, Brightness, Contrast, etc. Do I just need to make sure that those settings are at 0?
Thanks in advance.
Yes, leave all parameters at zero other than the one, or ones, that you wish to apply to a particular part of the image. So, with your example, everything should be at zero apart from the saturation parameter, which could be at say +20.
Not entirely sure what you mean about the pins; a pin shows where you began brushing in an adjustment, and you can of course apply multiple adjustments to areas of an image with different Adjustment brushes, so you might need to paint in that saturation you mention on one part of an image, but might need to bump up the contrast in a different part of the same image using a different ('new') brush. Each time you start off with a new brush, a pin is added at the point where you first begin to apply the effect. You can subsequently see which areas a particular brush is affecting by clicking on the pin - the painted area will be highlighted in red.
I'd spend some time reading up on Camera Raw if I were you. IMHO, one of the very best resources is the Schewe, Fraser book 'Real World Camera Raw', but there are many tutorials out there on the web.
Hope this helps