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A flash guide number calculator determines correct aperture and flash distance settings for photography lighting. Guide Number = aperture × distance. Higher guide numbers indicate more powerful flashes; knowing the GN lets you predict exposure without test shots.

Trin-for-trin guide

  1. 1Input parameters for calculation
  2. 2Apply formulas based on selected mode
  3. 3Review and export results

Løste eksempler

Input
Sample values entered
Resultat
Calculated outcome
Results depend on parameter values

Almindelige fejl at undgå

  • Wrong parameters
  • Missing adjustments

Ofte stillede spørgsmål

What does this calculator do?

Set parameters

How do I use this calculator?

Run calculation

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