Pen pressure for brush size in Photoshop for iPad

[Kfreud]

Using Photoshop for iPad, on iPad Pro gen 2 with Apple Pencil. 

I am unable to turn the brush toggle on for pen pressure for size, I am able to turn on the toggle for pressure for opacity.

is anyone else having this issue?

anyone have any suggestions?

[DaveJCummings]

Have you tried other brushes?  Which brushes have you tried it on?  I know certain ones I use like rough inking, I can't toggle that switch,  but ones like hard round, I can

[Kfreud]

Thanks for the suggestion - I am using the photoshop for iPad version and I only have one round brush.  I have tried every combination of the sliders with no success.

[M Shaw]

If you long press or double tap on the brush tool icon you will see the list of available brushes. The initial default brush is hardwired to have pressure enabled. The pressure setting can only be applied to brushes that do not already have that pressure dynamic enabled.

[Rex!!]

Apologies if this reply is too late, but is there a way that pressure sensitivity can be disabled for specifically the rough inker brush? Or is it also hardwired in?

[Michael J. Hoffman · Accepted solution]

I also cannot enable the slider, but my brush does respond to pressure for changing the size. Have you tried it? It's like a permanently on setting for me.