Yosemite Exhibition/Uncle Earl Brooks

Almost the same content. If you search for Brooks in the baycitizen page which appears in the link, the recent article appears as number 3 (approx.) in the list.
If Brooks was used by others because he access to the University development equipment and routine skills, then more complex scenarios exist and could explain why Brooks and his descendents have prints but, apparently, no plates.

OK I've got to get up to San Francisco to see this exhibit! Thanks Merg for the heads up!
:D