•If you press the high-speed sync button (HSS) again, high-speed sync is cancelled. When high-speed sync is cancelled, the shutter speed cannot be set faster than the sync speed.

•Taking photos in bright locations is recommended.

•The flash range with high-speed sync is smaller than with normal flash photography.

You can find the accurate flash range with high-speed sync by using the HSS flat flash (ISO100) table on page 41. Divide the guide number by the aperture to obtain the maximum distance of the flash range.

For example, with a 1/500 shutter speed and 28 mm focal length, the guide number is 8 according to the table. Since 8 (the guide number) divided by 4 (the aperture) equals 2, the flash range in this case would be 2 m.

The number is doubled when using ISO400.

•High-speed sync cannot be used with bounce flash.

•When using a flash meter or color meter, high-speed sync cannot be used because it interferes with the proper exposure.

Flash Sync Speed

Flash photography is generally associated with a maximum shutter speed referred to as the flash sync speed. This restriction does not apply to cameras designed for high-speed sync (HSS) photography (p. 26), since they allow flash photography at the maximum shutter speed of the camera.

Applications

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