Wireless multiple flash using SB-800 & SB-80DX

Archived from groups: rec.photo.digital (More info?)

I have 2 flash guns – SB-800 & SB-80DX – that I want to do wireless
multiple flash with. I have a problem in controlling the remote flash,
and wonder what’s people’s experience on this.

I use the SB-800 as the master on my D2X and the 80DX as the remote
flash, both set to use the SU-4 type wireless operation. The SB-800 is
set in Auto-Aperature mode, and the 80DX in auto wireless mode. The
camera is set in front-curtain sync.

When I fired the shutter, about three quarters of the time the remote
flash would fire at full output, beep for about 3 sec and then the
picture would turn out completely washed out with severe over-exposure.
The instruction manual describes this as a potential problem with the
remote flash detecting when to stop firing in sync with the master. But
the strange thing is that this problem does not occur consistently,
about one quarter of the time the remote flash is able to sync with the
master, with the flash output well controlled automatically and the
exposure spot on. I didn’t change the position of the camera, master and
remote flash. Yet sometimes it works and sometimes it doesn’t.

In following the instructions, I made sure there is a clear line of
sight between the master and the remote unit, and nothing blocked the
light from reaching the remote flash sensor. I took out the diffusion
dome from both flashes as well.

The setup works every time if I switch the remote unit to manual
wireless mode.

I am quite puzzled as to why this occurs. Can anybody shed some light on
this?

Cheers.