The G7 has a relatively long shutter button. It needs to be pressed half-way to set focus and exposure, then fully depressed to take the photo (along with flash). Perhaps the long shutter button gives the impression of a slow shutter lag when using flash.
The G7 has a lot of manual control options not found on point-and-shoot cameras. It acts a lot like a DSLR in that regard. It also uses Canon's DSLR flash exposure system - which uses a preflash prior to the final flash to determine exposure. The preflash system (which is not an anti-redeye system) does prolong the process of obtaining a flash exposure. This pre-flash for exposure is probably missing in the point-and-shoot cameras. This G7 feature allows it to use external flashheads for great exposure.
The pre-flash system can be bypassed by using the manual exposure mode - where the aperture and shutter speed are set manually. This speeds up the time of taking a flash exposure because there is no preflash.
I haven't tested the G7 yet with an external flashhead. Perhaps this is much faster in any exposure mode - just like a DSLR.
I find that the G7 HAS minimal shutter lag, even with the flash. It is the long flash exposure process with a preflash that gives the impression of shutter lag - but it is not shutter lag.
What I find slower when using flash is Canon's preflash system since it takes a longer time to do a flash exposure when two flashes rather than one is done. However, this is fine since it results in better flash exposures in the long run - particularly with external flashheads.
If you want better flash photos, definitely get an external flashhead, such as the 430EX. Better yet, get a light modifier such as Gary Fong's light sphere. With such a flash system, I think the G7 easily can take photos indistinguishable from DSLRs like the 30D.
I just bought a G7, and I'm really surprised at the amount of
shutter lag that it has when using the flash. It's like a camera
from the last decade. On the other hand, my SD700 has almost
instantaneous shutter responsiveness even with flash. What gives?
I've seen other posts about this, but has anyone posted a solution?
I find this unacceptable in a camera that is relatively expensive
(but is great in other respects). The lag seems to be about a half
second. The reviews I've read say that the G7 has minimal shutter
lag. Haven't they tested it with flash?