Focus stacking, also known as focal plane merging, z-stacking, or focus blending, is a digital image processing technique that combines multiple images captured at different focal distances to produce a greater depth of field (DOF) than any of the individual source images. Focus stacking can be used in any situation where individual images have an undesirably shallow depth of field, with macro photography and optical microscopy being two typical examples.

There are various focus stacking software options available, and Adobe Photoshop and Digital Photo Professional also provides focus stacking capabilities.