Multiple Exposure
Combining two or more exposures onto a single frame, either in camera or during processing.
Measured in
count
In depth
On film the exposures accumulate, so each must be reduced to avoid overexposure — two frames each at half the metered exposure. Digital cameras offer blend modes that handle this automatically, and the most reliable results come from combining a dark subject with a textured field, so each occupies areas the other leaves empty.
Examples in practice
A portrait against black combined with a frame of bare branches places the branches within the silhouette.