Lee,
I just came across the most recent user review here at dpreview on
the S3. This guy is a current G3 user and was not impressed with
the S3 at all.
For example:
by phusebox, 31 May 06
"Low-light performance is really really bad, even with the unusable
ISO800 setting. It When shooting in ISO100 for example inside my
canon G3 made a good photo at 1/60s whereas the S3 needed a 1/15s
shutter speed. It is 4 times as slow in low light one might say."
The G3 is f2 at the wide end and ISO 100 on the G3 is something close to ISO 160 on the S3. So the G3 should be 1 2/3 stops faster at the same ISO setting than the S3 at the wide end.
I think the G6 is about the best low-light Canon P&S made. It has a fast lens, a great sensor, RAW mode and a hot-shoe. It does lack IS. The S3 has a slower lens (1 stop at the wide end, 1/2 stop at the long end), a smaller, not-quite-as-good sensor, no RAW mode and no hotshoe. But you do get IS and all that focal-length range.
The S3 is capable of good performance in low-light. I've posted about that. But it's not as good as the G-series with those fast lenses and it's no-where near as good as my SLRs, especially when I use fast primes.
I've got a nice comparison from a wedding I shot last Saturday when my wife took a shot with the S3 at ISO 800 and f2.7 (wide open) at just about the same time I took a shot with my 5D with 35/1.4L at ISO 1600 and f1.6. Let me tell you, there's no contest. Nor should there be.
People need to learn how to use their cameras within their limitations and at their sweet-spots of performance. The S3 has a very wide sweet spot covering the entire aperture range on the lens, the entire zoom range (well, I haven't really tested the wide end yet), and up to ISO 400 if properly exposed. IS really does work up to 3-stops past 1/f (35mm equivalent) and beyond. Where it is weak is at ISO 800, especially when underexposed, when you need external flash, and when a lens faster than the one on the S3 is needed.
If anyone wants to put-down the S3 for it's limitations, I'll put my 5D and 35/1.4L up against their A95, G6 or any other P&S and also claim it "outclasses the [insert camera name here] by a great deal".
The S3 does what it does pretty well. It doesn't do well what the G6/20D/5D do well.
--
Lee Jay
(see profile for equipment)