All reasonably late model Canon cameras can withstand up to 250V in the flash sync circuit. This is because it is electronically isolated from the actual sync contacts. Your Rebel is a late model Canon.
However... some 283 flashes have been known to put out up to 600V on their sync circuit. You should make sure that you do not have one of these. 283 flashes originate from all over and exhibit different sync characteristics.
283 Safe for EOS?NO (old versions) Your call (new versions) Older units have been reported as high as 600V!Recent (post-'87) revised 283's ("Made in China") are safer with modern cameras, running around 9-10V. Bob Atkins reports some as low as 5V. Recently units marked "Made in Korea" have also appeared... measured at 8v by Andrew Cassino and Tony Bonanno. Kevin Omura used a Quantum battery and got a hefty 261.4V out of his (sn3012330), while Göran Samuelsson had two units with different voltages: 230V and 190V. Other reportshave had similar variety, up to 270V
I use a DynaLite studio flash system with my Canon 1Ds MkIII - no problems.
If in doubt, they make safe sync adapters that allow you to use any flash on virtually any camera.
Jim On Jul 11, 2010, at 2:59 PM, Marc James Small wrote:
Next question: are the flash circuits an modern digital cameras as sensitive to traditional voltage loads as were advanced electronic film cameras in the 1980's? I have a late Vivitar 283 with the lower trigger voltage but I still want to play it safe and there is no mention of this in the IB.Marc
