Compositing
Combining elements from several photographs into a single image.
Measured in
count
In depth
Convincing composites require matching four things: perspective, lighting direction and quality, colour and contrast, and grain or noise structure. The last is the most commonly neglected and the most immediately revealing, since elements from different ISOs sit against each other unmistakably. It is standard practice in advertising and prohibited in journalism.
Examples in practice
A product shot combines separately lit exposures of the bottle, its label and its cap into one flawless frame.