I'm guessing this docu was made in 1975. I read an article from 1976 which mentioned Hughes having "recently completed" documentaries on Caravaggio and Rubens.
(About that Rubens -- I did have it on VHS tape once, but alas, has been lost...)
This upload is from one of my surviving VHS tapes of the period. I recently tried to locate the DVD transfer I made of the tape, so I could do an HD conversion and upload of these clips, but I can't find that either! So here are these old clips again, but not too bad a transfer. The last one was done in bit better transfer.
in 2006, Hughes wrote:
In the summer of 1610, the boat on which he was traveling put into Porto Ercole, where Caravaggio was mistaken for some other miscreant and imprisoned. He was let go after only two days, but that had been enough; he contracted "jail fever" --the malignant typhus that killed so many of Europe's convicts in those days --and died within a week. There is no indication of where he was buried.
Michelangelo Merisi da Caravaggio (1571-1610)