I have had this problem for awhile now and thought I may have been able to see what the problem is so didn't post about it before.

Whenever I paint I rarely get a full 100% opaque mark with just one stamp. I have made sure my opacity is 100%  Hardness & force also I have at 100%. I am wondering could it be my dynamics?
Maybe it is the brush? Although I do not always use this brush. I have noticed this with other brushes as well. My brush and size are still set from some healing/cloning I was doing.

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