Nikon Autofocus Speedlight SB-22 Instruction Manual page 32

Shooting distance range in A1 or A2 mode
Regardless of the film speed and the corresponding
f/stop available at At or A2, the auto shooting range is
as shown in the following table.
Auto shooting range
Selector mode
At
A2
Normal
0.6-3.1 m
0.8-6.2m
With wide-flash
adapter
0.6-2.2m
0.6-4.4m