I have a problem with stroke in PS CS6. (2) When I use stroke on my curve line it looks pixelated and I don't know why ? (1) I did same line before and everything was clean and not pixelated.
Screen:
They both look pixelated to me.
I don't understand how you created that image. It looks like a (not completely) blue brush, with a soft inner glow and outer hard-edged glow? What's causing the color shift in the blue? Is it part of the brush you're using, or are you applying some sort of effect to it after?
Here is the zoomed version first one is broken definitely.
The problem is only with stroke. It doesn't matter what effect I add. Here is just red brush with stroke.
Try setting your brush to 100% Hardness and 1% Spacing, use your brush and then try the Stroke and the stroke should be somewhat smoother.
Tried it before, didn't help. It is not the brush problem but stroke.