I worked for Michael in 1970 as a studio assistant and darkroom technician. In reply to your request allbeit from about 7 or 8 years ago.
We used every sort of camera that was available, serious stuff was on 5x4 a de Vere monorail, I think. Contacts were on 35 mm.
I came upon this site while watching Bruce Forsyth being interviewed by Miranda and it made me think of Michael, mainly because we took pictures of Bruce a few times, mainly, while he was married to Anthea.
I hope this helps.
Oh and his studio was in Warren street possibly no 20.
He worked at Duchess House, 18-19 Warren Street in the 1970's. I was a spotty youth working for Agfa Gevaert on the floor above his studio so our paths crossed quite often. The question of his cameras & lenses seems to have been answered, I just wondered if anyone knew if he was still alive? It's a long time ago but I do remember seeing many 10''x8'' transparencies of very beautiful women he photographed often using Agfa film. CPL (Colour Processing Labs) were our landlords and they had a photo lab on the ground floor processing slide film and large print production. My then colleagues and I were once spraying water from the 3rd floor onto hapless passers-by (as you do) when we noticed Michael leaning out of the window below and yes he got a water bomb on the back of his head. He thought it was Les, his secretary, and to pay him back he put some rotting meat (fish bait) in Les's desk on Friday night. Needless to say by Monday morning the meat was maggot ridden and smelly, a nice welcome for Les, the innocent party. Sorry chaps! Michael's work was seen alot on photo magazine covers, his 10''x8'' sheet film shots often graced '35mm Photography' magazine!