Term - Guide number

Guide number

SWPP Photographic Glossary

Saturday 15th December 2018

SWPP

Glossary

Read all about it...
Stop Press...
Members in the News!

The Societies' Photographer
of the Year 2017
Results Announced!

Image Competition
Free entry for SWPP members.

Membership
Free Information Pack

Qualifications - An Overview

Guide number

Indicates the output, or power, of an electronic flash. You can use the guide number to work out the aperture or flash to subject distance by dividing either into the guide number. A photo term sometimes used to describe a flash factor, which provides a guide to correct exposure when using flash.

Information provided by: SWPP
More Photographic Terms