TTL flash — the automatic mode — meters through the lens and decides power for you, frame by frame. On the street that is exactly wrong: every frame gets a different exposure depending on what happened to be in front of you, and the flash hesitates while it pre-flashes and calculates. Manual power is the same light every single frame. Once you have found the power that works at your working distance, the look is locked and the flash fires the instant you press the shutter.

Direct means no bounce, no diffuser, no softbox. Straight, hard light from the camera position. Everything the portrait world tells you to avoid is the aesthetic here: hard shadows outlining the subject, colour snapped to attention, and that specific separated-from-the-background look that only on-camera flash produces. Softening it defeats the purpose.

Flash exposure and ambient exposure are two separate systems living in one frame, and understanding the split is the whole technique.

Aperture and ISO control the flash exposure. The flash pulse is far faster than any shutter speed, so the shutter does not affect it.

Shutter speed controls the ambient. Faster shutter, darker background; slower shutter, more of the world bleeds in. Your only ceiling is sync speed — usually 1/180 to 1/250. Go past it and a black bar creeps into the frame.

So the workflow is: set aperture, ISO and power for a correct subject at your working distance (the card's starting point: 1/8 power, f/8, ISO 400 at 1 to 2 metres), then choose how the background sits by moving the shutter alone. Same subject, brighter or moodier world.

The catch is distance: flash falls off with the inverse square law, so a subject at 1 metre gets four times the light of one at 2 metres. This is why flash photographers work at a fixed distance — the technique and zone focusing are natural partners.

Direct flash is one of street photography's oldest looks, not a modern affectation. Weegee shot New York crime scenes and night crowds in the 1930s and 40s with a press camera and a bulb flash, and the harshness *was* the honesty. Decades later, photographers like Bruce Gilden made close-range flash on the pavement a signature, and Martin Parr used daylight fill flash to give British leisure its saturated, slightly heightened look.

The common thread: flash announces itself. Nobody is under the illusion that the photographer was not there. That is why it reads as confrontational in daylight and theatrical at night — the picture admits it is a picture.

The technique demands proximity, and proximity demands manner. Move with confidence and warmth, not stealth — sneaking reads as predatory, openness reads as photography. If someone reacts, lower the camera, smile, and say what you are doing. A flash frame is unmistakable, so own it. Busy environments carry the look best: markets, night-life streets, events, crowds — places where a flash is one more burst of light in an already loud world.