We photographers seem to have a natural reluctance to whack up the ISO when the conditions get difficult. Okay, five or ten years ago, looking at a photo shot with very high ISO could be like looking through a snow storm – but that’s not usually the case today. I was chatting to a well-known picture editor last week, who said he’s not particularly troubled by high speed shooting, a bit of grain being much more preferable to even a tiny amount of blur.
When I'm shooting on the streets, I have my ISO set either to auto (with a minimum shutter speed set to 1/60th) or to 1600; in most of the lighting situations I encounter, the latter almost always guarantees a high shutter speed, allowing to to freeze the action of moving subjects - usually people.
So, to ensure a pin sharp shot, don’t be afraid of using high ISO – most modern cameras can take it in their stride.
What do you think? Do you have a particular 'ISO technique'?