I have had a message from Ken Orth, who are working together with Piet Schreuders to identify the photographers who took the photos used by Klaus Voormann for the "Revolver" cover. Amazingly, they have managed to identify the names of the photographers for all but two of the photos – one of Ringo and one of John. The images in question are these:
Can you help them to find out who took these photos? Bonus points if you can tell them the source where each photo was published (other than on the "Revolver" cover, of course), when and where each was taken, and the purpose of each. Use the comments section to share your information, or send me a mail if you're unable to comment in public.
When they have solved this puzzle, a full list of the photos and sources will be published. The search is on!