View Full Version : How to test maximum wireless sync. speed?

06-06-2011, 2:24pm
I have ordered some wireless triggers which should be here by the weekend. I wanted to do some testing and a review as these seem to be few and far between.

The tests I wish to conduct are distance (line of sight and with obstructions), FPS and sync speed. I know testing methods for distance and FPS, but testing sync. speed has be a bit lost.

I want to do this fairly comprehensively, so I was thinking I would set up a test subject in my makeshift studio with the strobe on a light stand pointing at the subject with no light modifiers. I would then set the shutter speed to 1/125, ISO to 400, flash power to 1/32 and adjust the aperture to suit the scene.

For the experiment I would increase the shutter speed 1/3-stop until I reach the maximum sync. speed for 1/32 flash power. I would then reset the shutter speed to 1/125, increase the flash power to 1/16 and adjust the aperture to suit the scene. I will repeat the shutter speed increases until I reach the maximum sync. speed again.

I will repeat these steps for 1/32, 1/16, 1/8, 1/4, 1/2 & 1/1 flash power each with the shutter speed steps in 1/3-stop until the maximum sync. speed is determined for each power level. The adjustment of the aperture will ensure the scene is exposed correctly making it easier to determine any dark areas caused by the shutter.

Does this methodology seem right? It doesn in my head, but I could be wrong.

Cheers, Adam.

06-06-2011, 4:47pm
The flash output power will not change the max sync speed, that is determined by your camera shutter. If the wireless triggers can get the flash to trip at a time in advance of the shutter (micro seconds here) then you may be able to synch above the camera max synch speed, based on the flash duration, which is usually linked to power output.

My PW Power ST4 and Mini TT1 allow me to shoot my Elinchrom Ranger at well above the camera max sync speed of 1/250 without trapping the shutter curtain. If I shoot the Ranger with a sync cord, clean frames until 1/320 (already above the 1/250 max sync speed) then after that the curtain shows slightly in the bottom of the frame. PW call it Hypersync and it works very very well in my experience, but I don't think cheapy Ebay triggers will offer the same benefit.