Depth of field
Taking a deeper dive into the world of sharp focus
f/8 at 14mm
f/8 at 17mm
f/8 at 50mm
f/8 at 85mm
f/8 at 200mm
f/8 at 300mm
Depth of field is the zone of front-to-back sharpness in a picture. The size of this zone is affected by aperture choice, the camera-to-subject distance and focal length. The last needs qualifying: if you swap from a wide lens to telephoto without changing the camera position, a wider lens will yield a deeper depth of field. However, keep the subject the same size in the viewfinder by shifting your position and, in theory, the depth of field remains the same. To see this in practice, I took this set of photos featuring model Caitlyn (PurplePort: @caillynj) using focal lengths from 14mm to 500mm at an aperture of f/8. Changing position to keep a constant size image in the frame isn’t a conventional way of working and it was tricky with the wider focal lengths as the lens was close to Caitlyn’s face.