>> |
Anonymous
Slow shutter speed makes the background well-exposed; it lets the light from back there bleed in. Your subjects, up close, are frozen, while the people in the background don't look quite as blurred because there's less detail on them to be blurred. Also, the flash will reach a lot of them some, too, probably.
Fast shutter speed makes the background go dark. An extreme example is this awesome photograph by David Alan Harvey. (NSFW, not that anyone cares about that on here.) If you want to learn to use flash right in at concerts, clubs, festivals, study DAH.
http://www.davidalanharvey.com/#a=0&at=0&mi=2&pt=1&pi=10000&s=7&p=1
All the ones you posted have a long shutter. Flashing when your exposure starts (normal/first curtain) freezes the subjects where they are when you press the shutter. Flashing at the end (second curtain) freezes them where they are at the end of your exposure.
|