Guest RA - the film was made in 1976 (some 20 years before the book) - I can't remember when camcorders became widely available, but I think it is possible Summer Walkers was shot in an older format? The other thing to consider is Tim Neat's intention with this documentary /observation? Also whether the Travellers themselves would have been willing to speak openly to Tim, even tho' Hamish was there? Hindsight is always a great thing! - I am just delighted that Tim Neat had the vision (and friendship with Hamish) that enabled him to make this delightful record of a lifestyle that was diminishing and by the time the book was produced, almost gone.