A new black and white film about the making of Breathless has more to teach photographers than it does filmmakers. Here is what to take from it.

Most of us learned photography through the exposure triangle. Aperture, shutter speed, ISO. Three variables, each one affecting the others. There is a second triangle. The Monochrome Triangle. Every time a photograph stops us in our tracks, all three points are working. Every time a photograph falls flat, at least one of them has failed.

There is a moment that most photographers recognise. You step outside with a camera and something shifts. The noise in your head gets quieter. You start paying attention differently. For a long time this was just something photographers said to each other. A feeling. An intuition. Now there is a growing body of research that explains why it happens and what it is doing to your mental health while it does.

A ship without an anchor is not free. It is lost. There is a difference between the two that most people miss. Freedom implies intention. Lost means drifting. Moved by whatever current happens to be running that day, with no fixed point to return to. A photograph without an anchor is the same thing.

Every beginner photography guide says the same thing. Keep the sun behind you. Light your subject from the front. Make sure everything is visible and evenly lit. It is practical advice. It is also, in black and white landscape photography, often completely wrong.

August Sander had a simple idea. He wanted to photograph the German people. All of them. Not the famous ones. Not the beautiful ones. Everyone. He called the project People of the Twentieth Century. He spent most of his life on it. He never finished it. And in not finishing it, he created one of the most important bodies of work in the history of photography.

There is an artist who makes extraordinary work. The walls of his studio are covered in it. Canvas after canvas, each one the result of genuine skill and real creative thought. He spends his mornings there, alone, adding to the collection. And when he is done he turns off the light and locks the door. The work is real. The dedication is real. But the studio has no visitors. And so the work hangs in permanent silence, speaking to no one.