I found this first at the BBC.

"An exhibition called 'Sight Unseen' has opened at the California Museum of Photography which showcases the work of twelve blind photographers from around the world."

I was fascinated by the process and the reason so I explored further and found the site of the
Exhibition at the California Museum of Photography . Some astounding photographs, the line that popped out at me from the BBC video was "ask any photographer they actually make photographs in their mind first" (or something close) and that is a statement I agree with. Anyway worth watching the short vid at the BBC and then explore the Exhibition at the website.