You are here:
< Back

A wider aperture lets more light onto the sensor, so is useful in lower light conditions, however wide apertures also reduce the depth-of-field (so out-of-focus parts of a scene are more blurred) and will tend to exacerbate lens design imperfections (and all lenses have some degree of distortion and imperfection). So as a rule try to keep the aperture constant across all your photos and rely on shutter-speed to change the exposure. Smaller apertures are recommended to get more of the scene in focus. Most lenses have an optimal aperture of around f/8 for the sharpest images (assuming the whole image is in focus), smaller apertures can create blurring through diffraction, but will make out of focus objects sharper.

Larger image sensors (e.g. 35mm “full frame” sensors) will always have a shallower depth-of-field than small sensors. e.g. the small sensors in smart phones have a very wide depth-of-field, meaning everything is more in focus. When modelling animal vision, or in general for objective photography it is better to have a wide depth-of-field.

Focus and Aperture