Here’s a super simplified explanation of front and rear curtain sync for your speedlight.
Front Curtain Sync. Triggers the flash at the beginning of the shutter duration, as the first curtain is opening. This is default mode for all flashes.
Front Curtain sync freezes the image of the subject. When using a slow shutter speed, the blur will be in front of the subject.
Rear Curtain Sync (aka Second Curtain Sync)
Causes the flash sync to wait, and not to trigger the flash until the end of the shutter duration, as the second curtain is about to start closing.
Freezes the subject at the end of the motion blur trail. When using a slow shutter speed, the blur will be behind the subject.
Rear Curtain sync can have no visible effect unless the shutter is slow enough to create some ambient motion blur (1/30 or slower).
SETUP: Try it both ways
½ second (0”5)
Manual flash mode
(We metered on the ball but then made it darker so the black would be black.
Your settings will vary)
SETUP: Rear Curtain Sync – CANON
SETUP: Rear Curtain Sync – NIKON
Press and Hold the FLASH MODE button and turn the rear dial to change to REAR CURTAIN SYNC
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Peggy Farren is an award winning, professional photographer, author, instructor and speaker. She’s been interviewed and featured on TV and in many national and local publications.