User's Manual

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If your camera’s maximum sync speed is slower than the number listed then you must
use the slower sync speed. Camera equalization does not give a camera faster sync
speeds than the camera is designed to handle.
For all shutters it can be assumed that a camera with faster external flash sync speeds (X
sync) will have faster shutter travel than cameras with slower X sync speeds. Faster shutter
travel times increase the allowable variance. The table above is based on the following
shutter travel times:
Focal Plane (35mm) – 1/1000 (0.0010) to open, 1/1000 to close
Leaf shutter at f: 8.0 – 1/2000 (0.0005) to open, 1/2000 to close
If a flash is generating light while the shutter is moving then you will see the shutter in the
exposure for focal plane shutters. You will see a loss in F stop exposure using a leaf shutter
if the flash is generating light as the shutter aperture opens or closes.
A variable flash duration will also affect these calculations. A slow flash is visible for longer
and more likely to affect exposure while the shutter is in motion. A short flash duration
reduces the likelihood of timing variances affecting the exposure.
It is difficult to measure a shutter’s travel time or a flash units duration and it usually
requires extremely expensive test equipment. Some electronic flash manufacturers print
their flash durations in their manual. The best method for understanding your equipment’s
equalization capabilities is to shoot many test exposures over a range of settings.
Recommend Equipment for the best results
Consistent lag time cameras
Cameras with fast sync speeds
Electronic flash equipment with short flash duration
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