Quote Originally Posted by Steve Smith View Post
Thanks. I think I have it now.

I found a manual for the modules on the Butkus site. I think you're right that the N2 is s second generation Nikon module. It has an FG setting which works for the Nikon FG and FE2 and a couple of others. I think the FG was the first (or one of the first) to use TTL flash metering.

According to the manual, switching it to FG should make it work in TTL mode - but strangely, the other end of the switch is marked for manual/TTL which should also work.

i.e. if it has a flash attached which can give the stop signal to the flash, it will work in TTL mode whereas if this signal is not received (not sent) it will fire at full power. The other settings are controlled by the on board sensor.

The FG may be the first Nikon where in TTL flash the camera sends out the quelch signal to shut off the flash. The first TTL Nikon was the F3 but it sends out the light value to the flash so the flash has to determine when there is enough light to shut itself off and also the ISO information must be sent from the camera to the flash or else has to also be set on the flash.