Yea I watched the programme, very interesting ok. She must have shot thousands of rolls of 120 film format during her photographic time as a 'street photographer', I wonder if she developed these films herself or left them in for processing and printing etc..? That bit was not clear.
Vivian mainly used a Rolliflex Twin Lens Reflex medium format camera, only 12 shots per roll, a lot of film changing. These cameras now sell for big money second hand value....
Ive used a few 'TLR's over the years, Mamiya C330s, Rollicord, Yashicamat 124G, Lubitel etc...... Great fun format, slows you down and makes you think about your composition/exposure.