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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.

Guida passo passo

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

Esempi risolti

Ingresso
Sample values entered
Risultato
Calculated outcome
Results depend on parameter values

Errori comuni da evitare

  • Wrong parameters
  • Missing adjustments

Domande frequenti

What does this calculator do?

Set parameters

How do I use this calculator?

Run calculation

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Impostazioni

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