trigger/sync voltage

[David Brown]

Just got a Sony a850. It has a "pc" flash terminal and I would like to use one of my old "potato masher" strobes, (Honeywell Strobonar and the like), in addition to some older studio strobe units.

The camera's manual says to use a flash with a sync voltage of less than 400V. The manual for the Strobonar does not address the trigger or sync voltage. My extensive internet research yielded the advice to measure the voltage of the strobe's output.

OK. How do I do that?

I have a volt meter. Do I charge up the strobe and measure across its PC jack?


EDIT: Sure - 10 minutes later I think I found the answer:

Secrets of Powershot Flash Photography

 

[toyotadesigner]

It's only in German, but maybe it can help you a bit - the model names are identical ;-)

Blitzgerte-Zndspannungen | plainpix.com

 

[Jim Jones]

Quickly skimming through David's link turned up an error: "Cameras from the 1950's-70's even have two different flash settings, each with minutely different timings: "X" for strobes, and "M" for flashbulbs (which needed an extra 1/250th of a second or so to ignite)." The delay for class M flashbulbs is 17 to 19 milliseconds (about 1/55 second). It is the F class flashbulbs that requires a delay of about 4 ms, (1/250 second). Much of the other information does seem valid.

 

[RalphLambrecht]

Just got a Sony a850. It has a "pc" flash terminal and I would like to use one of my old "potato masher" strobes, (Honeywell Strobonar and the like), in addition to some older studio strobe units.

The camera's manual says to use a flash with a sync voltage of less than 400V. The manual for the Strobonar does not address the trigger or sync voltage. My extensive internet research yielded the advice to measure the voltage of the strobe's output.

OK. How do I do that?

I have a volt meter. Do I charge up the strobe and measure across its PC jack?


EDIT: Sure - 10 minutes later I think I found the answer:

Secrets of Powershot Flash Photography

just get a wireless radio trigger and you don't have to worry about this issue any longer.
good luck

 

[toyotadesigner]

You might check this list:

Photo Strobe Trigger Voltages

 

[analoguey]

For PC-sync, it should not matter. The flash voltage is for the hot-shoes.

Sent from my LT26i using Tapatalk

 

[RalphLambrecht]

You might check this list:

Photo Strobe Trigger Voltages

yes, I remember reading this and checking my trigger voltages with shocking results. wireless triggers are the way to go, but still, need to be tested too;mine were all around 0.5V;which is very safe.also a comparison of the ISO standards for cameras and flash units in regards to trigger voltages are sobering;they do not match.a Hasselblad repairman told me that even the robust Zeisslens contacts show the signs of high trigger voltages; they can handle them for many years of professional use, but the wear is viable and doesn't make them better;something to watch when you buy lenses from a studio pro.