Half-frame Format
A 35 mm format using an 18 by 24 millimetre vertical frame, doubling the number of exposures on a roll.
Measured in
mm
In depth
Because the frame is oriented vertically within the horizontal film strip, a half-frame camera held normally produces portrait-orientation images — an unusual default that shapes how people compose with it. Seventy-two exposures per roll made it economical, and modern interest has revived it as a deliberately grainy, diaristic format.
Examples in practice
A half-frame camera turns a 36-exposure roll into 72 frames, encouraging shooting in loose sequences rather than single pictures.