>The older SB22 flash is said to not work with the PW flex / >mini system. But I wonder if this simply means they will not >work in iTTL mode. When using an AC3 controller with the flex >TT5, will the SB22 be 1) firing and 2) responding in manual >mode to the power fractions of the AC3?
No. The SB-22 is not compatible with the Nikon Creative Lighting System. The SB-22 uses the Film TTL flash control system that is not compatible with DSLR's or Speedlights that are CLS i-TTL flash control compatible because they are two completely different systems.
>In other words will it fire at half or quarter power if that is >what the AC3 is set for?
No. The SB-22 will only work when it is set to Non-TTL Auto or Manual flash mode. If I remember correctly when the SB-22 is set in Manual flash mode it will only fire at full power.
To take full advantage of the PW Control TL system with the AC3 zone controller you will have to use a Nikon SB-600, SB-700, SB-800, SB-900, or SB-910. Good Luck and Enjoy your Nikons!