In article <4d16fu$5qh@vu-vlsi.ee.vill.edu>, mobasser@vu-vlsi.ee.vill.edu says...

>How is this done?. Is it between contact and the ground?. Is it >measured when the flash is fired or is the voltage there all the
>time?

The voltage is measured between the large center contact in the
center of the flash shoe and the (hidden) terminal that contacts
the edge of the body flash shoe when it is mounted. BE CAREFUL!
Start the voltmeter on the 1000 volt range, and USE INSULATED
PROBES and DON'T TOUCH THE METAL PARTS! If no significant voltage
is read, drop the scale to the 10 volt range. The "trigger"
voltage is on the terminals when the flash is on and charged.
Hope This Helps