I have F&H lenshoods for both my Automat MX in bay I and my 3.5F in bay II. The outer dimensions are identical and both fit my F&H graduated filter holder. In addition to the original glass graduated yellow filter I cut down a Cokin graduated grey filter to fit. So questions: would I be correct in assuming the bay III hood would also have the same outer dimensions? And, for my new Rolleiwide, how about the bay IV hood? Now there are at least 3 versions of this hood: The original F&H one produced in the sixties, the modern one produced for the 50mm FW, and the Chinese copy sold on Ebay. The bayonet IV hood is a stubby little thing and the only reason I can deduce for that is to keep the same outer dimensions as the rest of the hoods. I contemplate buying the Chinese copy and using my graduated filter holder to use cut down Cokin filters instead of the expensive original or B+W or Heliopan filters in bay IV. Does anyone think that will not work?