Nikon Autofocus Speedlight SB-22 - Bounce Flash Photography; Bounce Flash Photography Procedure

Guide Number
In M or MD mode, without referring to the aperture se-
lection/shooting distance range panel, you can de
termine the f/stop by using the following equation:
,, guide number
f/stop = ----------- - --------------------- - —
flash-to-subject distance
See the table for guide numbers at various film
speeds.
Guide number at various film speeds
Unit; m (ft)
Normal
With wide-flash
adapter
Mode
selector
M (manual)
MD
M (manual)
MD
1600 100(328) 32(105) 70(230) 22 (72)
800 70(230) 22 (72)50(164) 16(52)
o
400
50(164)
16(52) 35(115)
11 (36)
200 36(118)
11 (36) 25 (82) 8(26)
too 25 (82) 8(26) 18(59) 5.6(18)
50 18(59) 5,6(18)12.5(41) 4(13)
25
12.5(41)
4(13) 9(30) 2.8 (9)