Folks, I will be the first to admit i'm not the sharpest hammer in the pantry, but must admit I'm stumped on this one:
In PS, when painting (be it color, or for D&B) what is the difference between Opacity and Flow? They seem to do similar things - dropping one to 20% appears to have a similar effect as dropping the other to 20% .
I know it has something to do with building up a color or effect, but right now I'm doing it all trial and error -- knows there's a logical approach.
Flow is the amount of paint you apply. Opacity sets a limit on how much it can be.
In other words, if you're brushing up bit by bit, at say 15% flow, and set opacity to 30%, then no amount of brushing will increase the density beyond 30%.
Try setting both at 100% and brush some black in a stripe. Then set opacity to 25% and brush a parallel stripe: all we become clear.
***Actually that isn't quite right, hang on****
Here, from help:
"'Flow' sets the rate at which color is applied as you move the pointer over an area. As you paint over an area, keeping the mouse button down, the amount of color will build up based on the flow rate, up to the opacity setting. For example, if you set the opacity to 33% and the flow to 33%, each time you move over an area, its color moves 33% towards the brush color. The total will not exceed 33% opacity unless you release the mouse button and stroke over the area again."
Note that you can continue to "build up" density by releasing the mouse buttong and starting a new stroke.
Opacity sets how dark a line can be on one click. Flow adjust how many passes it will take over that same area before it reaches the density limited by the Opacity. 100% flow means you will reach that density in one pass, whereas 50% flow requires two passes or so.
Once we start getting into multiple clicks then it all starts getting confusing for me.
So I tend to use low opacity, high flow so I get a subtle but full effect on one pass. If I need more o will make another pass.
Really terrific. I'll never keep them straight, though...
Would it help keep them straight if you think of everything you do with one click of the mouse being like everything you do in a new adjustment layer (say like making multiple adjustments via NIK Color effects Pro) and think of the opacity setting being like the opacity setting for that layer being made ahead of time...
