When should I switch on the flash?
With most sports you’re too far away from the action for flash to be effective, so leave it switched off. But there are occasions when flash is a powerful tool for capturing a moving subject crisply.
For shots of skateboarding, cycle races, or any other sport where you can safely shoot within three metres of the action, flash will fill shadows, brighten colours and freeze the action.
Flash has a duration as short as 1/40000 sec in full auto mode at short subject distances, with a maximum burst length of around 1/850 sec (on full manual power).
The maximum shutter speed you can use with a built-in or hotshoe flash is approx 1/200 sec, but if the flash is the main light source, the flash duration is the effective shutter speed.
If the ambient light and flash are lighting the subject significantly, the ambient light can create a ghost image around the subject, giving the shot a strong action feel.
Results are often good with the flash set to its auto E-TTL II mode and your SLR on Av. This balances exposure for the foreground and background.
Then use Exposure Compensation to lighten or darken the background (if necessary) and use flash Exposure Compensation to darken or lighten the flash-lit foreground.
PAGE 1: How do I choose the right shutter speed?
PAGE 2: How slow should I go for motion blur?
PAGE 3: Do I need the motordrive?
PAGE 4: When should I switch to manual focus?
PAGE 5: Why should I keep both eyes open when using the viewfinder?
PAGE 6: How slow should I go at night?
PAGE 7: How do I set up for low-light events?
PAGE 8: What shutter speed do I use for zoom bursts?
PAGE 9: When should I switch on the flash?
PAGE 10: When should I use second curtain sync?
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