Flash synchronization for digi cam

[Falcon]

Hi,

Can someone explain to me what is Flash synchronization? I am kind of confused with this term. Must the shutter speed be set to match this "speed"?

[ckiang]

Quote: Originally posted by Falcon Hi, Can someone explain to me what is Flash synchronization? I am kind of confused with this term. Must the shutter speed be set to match this "speed"?

The flash sync speed is the shutter speed where you can achieve perfect synchronisation with the flash. That is, the shutter is fully open when the flash goes off. For cameras with a focal plane shutter like SLRs and some rangefinders like the Leicas, Voigtlanders, etc, this is very important. Focal plane shutters are made up of 2 curtains. The first curtain opens, then the 2nd curtain closes shortly after. At the correct sync speed (and below), the shutter will be fully open. At higher than this, the 2nd curtain closely follows the 1st curtain and the shutter is never fully open, but is of a "travelling slit". If you then shoot at this speed, you get partially exposed pictures.

For leaf-shutter cameras where the shutter is built into the lens, this is not a problem and the flash can probably sync at any speed. Most consumer digital cameras does not use focal plane shutters and thus should be able to sync at any speed too.

For focal plane shutter cameras, you can use any speed below the flash sync. In fact, doing so lets you achieve better ambient/flash exposure, and if you use an even lower speed, you can get some pretty interesting effects.

Regards
CK

[mpenza]

Quote: Originally posted by ckiang For leaf-shutter cameras where the shutter is built into the lens, this is not a problem and the flash can probably sync at any speed. Most consumer digital cameras does not use focal plane shutters and thus should be able to sync at any speed too.

Good explanation

Just want to add that the flash duration will become the limit to the sync speed for cameras which do not use focal plane shutters. Since, flashes are generally around 1/1000s, this is roughly the fastest you could sync.

[Falcon]

Tks guys.

[Falcon]

Quote: Originally posted by ckiang For focal plane shutter cameras, you can use any speed below the flash sync. In fact, doing so lets you achieve better ambient/flash exposure, and if you use an even lower speed, you can get some pretty interesting effects. Regards CK

This part should concern me more. I am using Oly c2100uz. I am trying to use the flash to brighten up the subject(marco shot) so that I can achieve a faster shutter speed. Does that mean I should set a shutter speed that is equal to flash sync speed? Sorrie, I am a bit blur here.