Flash Shutter Speed Limitations

[dwservingHim]

Ok, so you know how basically every camera has a flash sync speed of around 1/200 of a second. This seems like such a limitation. How do you shoot highly active events with a flash if you can't get a faster shutter than that. I've seen action photographs of like car races where they use a flash, but it's really sharp. HOW? Thanks

[RichardTaylor]

The flash duration can be much shorter than the shutter speed.
For example My Canon 580ex it is normally <=1.2ms

[Tzetsin]

What he means is that the Flash basically "becomes" your shutter speed. The 1.2ms speed of the flash freezes the action regardless of your actual shutter speed.

Try this.

set your shutter speed to 200, set your flash so the expersure is correct, then decrease your shutter speed and take the shot again. You should notice that the image pretty much stays the same. This is because the flash is overrulling the shutter speed in a sense. This does not apply to aperture though.

[dwservingHim]

So what do you mean by setting the flash exposure correctly? You mean put the flash unit on manual and have it's speed be shorter or longer than what the camera is shooting at? Thanks

[Tzetsin]

put the flash in manual, set the shutter to 200, adjust the aperature and flash intensity so the image is properly exposed take a reference shot, then reduce the shutter speed. the resulting shots should be about the same exposure as the reference shot.

[dwservingHim]

Just tried it, that's awesome. But why does it do that and how do you apply that? How does this help in the process of trying to capture a fast moving subject?

[Tzetsin]

that flash of light is faster than any fast object right. speed of light and all that.

[dwservingHim]

Right, but wouldn't there still be instances where I'll need my shutter speed to faster than 1/200th of a second? Like taking indoor pictures of a fast sport where there is ambient light and then my flash, but 1/200 is still blurry. Is there anyway to get the shutter speed faster than 1/200th?

[Tzetsin]

if your shots are still blurry you need to jack up the flash's intensity. See, its the flash that burns the image to the sensor, but the shutter is open long enough to cause blur if its not bright enough. Try taking somebody you know and having them run across the frame as you hit the shutter with the flash. you should notice, if the flash is strong enough, that no matter how fast they run it will be sharp. but if you lower the intensity of the flash, eventually you'll end up with motion blur.

There is absolutely no way to increase the sync speed unfortunately, you just have to get stronger lighting.

[RichardTaylor]

@dwservingHim

use high speed synch (if possible).