This command adds random dots to an image, emulating the effect of using high-speed film such as 1600 ISO. Add noise is also used to reduce bands of lines in selections that have been feathered or gradients, as well as to give a more realistic feeling to areas of your photo that have had heavy retouching done.
add noise, gaussian blur, grain, and craquelure filters, all the while using render clouds in the respective
A layer mask is used to hide portions of a layer and reveal portions of whatever layer is below it. You can modify the mask by using the brush tool and painting in either black or white.
layer masks. This is an effect-rich but fun tutorial to watch!