What is the depth of field of an 18-55mm f/5.6 kit lens on APS-C?
At f/5.6 and 5 meters on APS-C (1.5x-labeled Nikon/Sony/Fujifilm format), an 18-55mm kit zoom's wide end already reaches beyond its own hyperfocal distance — everything from about 1.92m to infinity reads sharp. At the 55mm long end, the same distance and aperture produce only about 1.77m of total depth of field, a real, finite window rather than a stretch to infinity.
Why the Kit Zoom's Wide End Is So Forgiving
18mm's hyperfocal distance at f/5.6 on this sensor is roughly 3.09m — shorter than the 5-meter test distance used here, which means the far limit has already reached infinity. This is exactly why beginner landscape shots taken at the wide end of a kit zoom tend to come out acceptably sharp throughout even without careful focus technique, while the same lens zoomed to 55mm demands real attention to where focus actually lands.
What Changes This Comparison
A closer subject distance would pull the 18mm end's near limit closer too, and could eventually bring its far limit back to a finite number rather than infinity. At 55mm, stopping down further (many kit lenses reach f/8 or narrower at the long end) widens the sharp zone somewhat, though it stays far short of the wide end's essentially unlimited depth of field at the same aperture.
Compare both ends for your own distance in the DoF & Hyperfocal Calculator — pre-filled at the 18mm end; change focal length to 55 to see the long end.
Frequently Asked Questions
Why does my kit lens photo look sharp everywhere at 18mm but not at 55mm?
At 18mm, the hyperfocal distance at typical apertures is short enough that a normal shooting distance already puts the far limit at infinity, giving near-total sharpness by default — at 55mm, the same aperture and distance produce a genuinely finite depth-of-field window instead.
Is f/5.6 a slow aperture for a kit lens at 55mm?
It's typical — most variable-aperture kit zooms narrow from around f/3.5 at the wide end to f/5.6 or f/6.3 at the long end, a real optical-design tradeoff that also means the long end offers less background separation than a fixed-aperture lens would at the same focal length.