Guide Numbers for the Speedlite 470EX-AI
Article ID: ART172767 | Date published: 12/19/2018 | Date last updated: 12/19/2018
 

Description

Guide Numbers for the Speedlite 470EX-AI

Solution

Guide Number (ISO 100, in approx. meters / feet)

Normal Flash (Full Output)/Quick Flash
Flash Coverage (mm) 14 24 28 35
Normal Flash (Full Output)  14.0 / 45.9   25.0 / 82.0   26.0 / 85.3   29.0 / 95.1 
Quick Flash Equivalent to approx. 1/2 - 1/6 of full output
 
Flash Coverage (mm) 50 70 80 105
Normal Flash (Full Output) 33.0 / 108.3 40.0 / 131.2 42.0 / 137.8 47.0 / 154.2
Quick Flash Equivalent to approx. 1/2 - 1/6 of full output
 
Manual Flash
Flash Output Flash Coverage (mm)
14 24 28 35
1/1 14.0 / 45.9 25.0 / 82.0 26.0 / 85.3 29.0 / 95.1
1/2 9.9 / 32.5 17.7 / 58.1 18.4 / 60.4 20.5 / 67.3
1/4 7.0 / 23.0 12.5 / 41.0 13.0 / 42.7 14.5 / 47.6
1/8 4.9 / 16.1 8.8 / 28.9 9.2 / 30.2 10.3 / 33.8
1/16 3.5 / 11.5 6.3 / 20.7 6.5 / 21.3 7.3 / 24.0
1/32 2.5 / 8.2 4.4 / 14.4 4.6 / 15.1 5.1 / 16.7
1/64 1.8 / 5.9 3.1 / 10.2 3.3 / 10.8 3.6 / 11.8
1/128 1.2 / 3.9 2.2 / 7.2 2.3 / 7.5 2.6 / 8.5
 
Flash Output Flash Coverage (mm)
50 70 80 105
1/1 33.0 / 108.3 40.0 / 131.2 42.0 / 137.8 47.0 / 154.2
1/2 23.3 / 76.4 28.3 / 92.8 29.7 / 97.4 33.2 / 108.9
1/4 16.5 / 54.1 20.0 / 65.6 21.0 / 68.9 23.5 / 77.1
1/8 11.7 / 38.4 14.1 / 46.3 14.8 / 48.6 16.6 / 54.5
1/16 8.3 / 27.2 10.0 / 32.8 10.5 / 34.4 11.8 / 38.7
1/32 5.8 / 19.0 7.1 / 23.3 7.4 / 24.3 8.3 / 27.2
1/64 4.1 / 13.5 5.0 / 16.4 5.3 / 17.4 5.9 / 19.4
1/128 2.9 / 9.5 3.5 / 11.5 3.7 / 12.1 4.2 / 13.8