I have his book "Open Skies" ,1989, comprising pictures taken near his home in Somerset.
He seems to differ from most B/W landscape photographers in heavily burning in his skies.
May be part of the secret of his success?
I think he's totally in alignment with the English pastoral landscape tradition of Gainsborough, Turner, Constable, etc. In a country that can have four seasons in one day the sky and the weather is ever present and important, it's not just an accessory to the hard bits of the landscape but a feature that makes it complete. It would be interesting to know which music he would be humming while pressing the shutter, but I bet it would be also in the English pastoral tradition of Tallis, Dowland, Vaughn Williams, Elgar, etc. So there are clues in the film, he talks of the trees without their leaves showing their true character, he talks of the landscape being moulded by the weather, he talks of the way the sky changes the feeing of landscape, he talks of threat and tranquillity, and all these things are expressive ideas despite him saying he is 'only' a photographer. He's photographing not just what he's seeing but also what he's feeling, something his war work never allowed.