ZBrushCentral

Question on photoshop / zbrush

I am following along with a tutorial about deforming geometry via alpha channel maps in zbrush…using maps made in photoshop…

I am learning both, so I was wondering about this image attached…

How do I make that map in photoshop for “fine” detail in alpha masking…

Also, making the black and white maps, is it simply a technique of adjusting black and white parameters? (which is what I have been doing///)

THANKS

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