Photography

Estimate the longest shutter speed for stars before visible trailing appears.

Convert focal length and aperture to their full-frame equivalents.

Calculate hyperfocal distance, near/far focus limits and total depth of field.

Solve for the setting that keeps the same exposure when you change one.

Calculate horizontal, vertical and diagonal angle of view from sensor size and focal length.

Estimate flash distance from guide number, ISO, aperture and power setting.

Work out the new shutter speed after adding a neutral-density filter.

Plan a time-lapse: solve interval, frame count, clip length and storage.