Photography Math: Exposure Value, f-Stops, Depth of Field & Hyperfocal Distance

What you'll build

What you will be able to do

Each lab ends with a concrete result that you build yourself and the checker confirms, cell by cell.

• Turn seven real camera settings into exposure values, normalise them to ISO 100 to compare scene brightness, and work out the shutter time a metered scene needs.
• Derive the f-number scale from √2, see how each stop halves the light, and build a table of equivalent exposures for a portrait shoot.
• Turn typical scene brightness values into shutter times, round them to the nearest full stop, and convert incident and spot meter readings into EV₁₀₀.
• Calculate sensor diagonals and crop factors for five sensor formats, then the full-frame equivalent focal length and the horizontal angle of view of five lenses on an APS-C body.
• Set a circle of confusion from the sensor diagonal and calculate the near limit, far limit and total depth of field of an 85 mm portrait lens at eight apertures.
• Build a two-way hyperfocal table (focal length × f-number) with mixed references, look up one value with INDEX/MATCH, and calculate the sharp zone when you focus closer.
• Scale a flash guide number for ISO and power, find the maximum flash distance, and see in stops how fast flash light falls off behind the subject.
• Compare the 500 rule for star photos with a pixel-level limit, chart both against focal length, and calculate the longest shutter time for a running subject.