I have finaly completed the rigging of my model and need to paint the weight.

Everything is simple except that when I try to paint and area, for exemple fingers, I sometime paint by accident another, ex: torso, and dont notice it until I do some testing by moving the squeleton.

This is very frustrating because I have to fix it and while doing so I also happen to paint on another area and the problem repeat itself over and over...

So is there a way to make sure that once I paint weight, it will never change?

Or to prevent Maya to add weight to area that are not directly connected to the one I am working on?

Thanks!