I'd like to hookup an old Sumpak Auto 444D or an eaqualy old Canon 277T speedlite to my 990. One store clerk told me I just needed a cable and a bracket while another told me I might fry the 990. Anyone know the truth, the whole truth and nothing but the truth.

I searched the past posts but with the word "flash" I get a ton of flashcard responses.

-- bill (this_old_house@pobox.com), July 14, 2000

Answers

This seems to be a subject of great discussion among Nikon owners... :-)

Have a look at: http://www.panix.com/~donwiss/flashfaq.html

You'll find a bunch of links including one to a list of flashes compatible with the Nikon digitals. The trick from what I've gathered is to find a flash unit that has a potential of 5 volts(DC) or less across the contacts when charged. You can check it with a volt meter.

Several people posting to the list of compatible flashes seem to be getting along fine with units that put out in the neighborhood of 8 volts. I read somewhere else that Nikon has also officially stated 250 volts is the max, but I think they may be talking about any high voltage spikes from back EMF or ringing that occur when the flash is fired. You'd likely need a scope and darkened room(so you could see the fast spike on the phosphor screen of the scope) to measure them.

I was looking to see what the flash unit voltages range because I have a Vivitar2000 I'd like to try with a Toshiba PDR-M70. I checked the voltage across the hot shoe terminals on the bottom of the flash and found several hundred volts DC so decided to err on the side of caution and check further... That's how I found the Nikon links.

Hope it helps.

-- Gerald M. Payne (gmp@surferz.net), July 14, 2000.

As I've suggested before, get a flash "slave-trigger" and strap it to the camera flash with black plastic tape. Plug your main flash into the slave-trigger. Totally safe, as far as the camera's concerned, and the black tape prevents the built-in flash from affecting the exposure.

you're quite right Gerald, older flash units can have several hundred volts present at the sync socket. (Although the current is limited to picoamps)

-- Pete Andrews (p.l.andrews@bham.ac.uk), July 18, 2000.

As I've suggested before, get a flash "slave-trigger" and strap it to the camera flash with black plastic tape. Plug your main flash into the slave-trigger. Totally safe, as far as the camera's concerned, and the black tape prevents the built-in flash from affecting the exposure.

you're quite right Gerald, older flash units can have several hundred volts present at the sync socket. (Although the current is limited to microamps)

-- Pete Andrews (p.l.andrews@bham.ac.uk), July 18, 2000.