Shooting Portra 400 in flat autumn light

For a long time I rated every roll of Portra 400 at 200 and called it a safety margin. On bright days that works. Under a flat, overcast sky it mostly produced dense negatives and a scanner that had to work harder than it needed to.

What changed

I started metering for the shadows I actually cared about and rating the film at box speed. The negatives came back thinner but printable, with more separation in the greys that make an overcast day look like an overcast day instead of a muddy one.

The other change was patience. Flat light rewards waiting for a small gap in the cloud; a single stop of extra light is often enough to lift a whole frame.