They're meant to be unobtrusive, if you notice, they stay on until the lens locks focus, then shut off. They're only on as long as needed. A continuous light will not be a problem for the focusing system, but in low power flash situation it may show up in the photo. In a club situation, most of the time you're blowing out the ambient with your flash, so you shouldn't have an issue with the little LED showing up in the photos.
Andrew Rodgers
Perfected Perspectives -- Photography by Andrew Rodgers |
Andrew Rodgers (acedrew) on Twitter
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Canon 50D 24mm, 50mm, 100-400mm, 28-135mm
Panasonic Lumix TZ-3 Yeah, I have optical image stabilization and a 10X lens, it also fits in my pocket.
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