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Diffraction Limit

Definition

The aperture threshold below which wave diffraction at the aperture edges degrades resolution more than the narrower aperture improves depth of field. Approximately f/11-f/13 on a 24 MP full-frame sensor.

Related terms

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Depth of Field (DoF)
The zone of acceptably sharp focus around the focused plane; controlled by aperture, focal length, and subject distance. Critical for close-up evidence...
Dynamic Range
The ratio in exposure stops between the brightest recordable highlight and the darkest shadow detail above the noise floor; typically 12-14 stops...
F-Stop
The ratio of focal length to aperture diameter, expressed as f/number. Lower numbers mean wider aperture, more light, and shallower depth of...
Focus Stacking
A computational technique combining multiple images focused at sequential depths into a single all-in-focus image; used for three-dimensional evidence with relief exceeding...
ISO
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Oblique Lighting
A lighting geometry with the source at 5-30 degrees to the evidence surface, casting long shadows that reveal surface relief. Standard for...
Ring Flash
A circular flash tube mounted around the lens that illuminates from all azimuths simultaneously, producing uniform shadowless illumination used for bite-mark and...
White Balance
A camera setting that corrects for the colour temperature of the ambient illuminant, ensuring neutral colours render as neutral. Manual white balance...

Explained in

  • Forensic Photography: FundamentalsThe aperture threshold below which wave diffraction at the aperture edges degrades resolution more than the narrower aperture improves depth of field. Approxim...

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