Ad 1) Are you sure you are talking Opacity and not Flow?
Ad 2) Which Brushes? Could you provide a screenshot (with Brush Tip Shape in the Brush Panel visible)?
How can Brush Spacing not be on?
Yeah, I'm having the exact problems as you. Actually, I think both of them are one. I set Opacity to about 50% then tried to reduce the Spacing to 1% but the problems still persist. My tablet works fine in Paint Tool SAI, so there must be some problems with Photoshop.
I use Photoshop CS6 on Windows XP with a Wacom Bamboo Create.
Could you please post a screenshot to illustrate the issue?
Hi, I've been having the same problem!
It's very annoying when rendering something delicate and your fine, pressure sensitive brush all of a sudden turns into a big marker.
I'm using CS6 with Windows 8 and a Wacom Cintiq.
Photoshop Experts, please help us!
This should illustrate the problem- The brush was set with size and opacity set to pen pressure.
I just filled the screen row by row, left to right with marks. As you can see, at random times the brush loses all size and opacity sensitivity.
Imagine delicately trying to render something like hair and this happening regurlarly at random times!