razorc03 wrote:I'm not sure if the low-light sensors are junk on the S410. I just did a comparison between the S410 and the FH20.
Settings on both: ISO 100, EXP +2
Um, your S410 picture was taken with a 1-second exposure. Your FH20 picture was taken with a 1/8-second exposure. The S410's shutter was open for 8 times longer and it thus got 8 times more light. This comparison illustrates the difference in exposure times, not sensor quality or low-light performance.
The problem here is with the auto-exposure: you tell the camera to use ISO 100 and no flash, and it will try to compensate by increasing exposure time (the +2EV just tells it to compensate even more) (for the sake of simplicity, I'm going to ignore the aperture since in situations like this, it doesn't make too much of a difference). Most cameras don't support long exposure times when using auto-exposure; for most cameras, if you want your a 1-second exposure or longer, you need to manually tell the camera what you want (I think you have to do some menu-digging on the FH20; on the ZS6, it's much easier--just set the mode dial to "S" to control the exposure time). So the problem here is that the S410's auto-exposure is okay with setting a 1 second shutter, while the FH20 balks at going so slow in auto. It's not that the FH20 can't; in fact, the FH20's (and ZS6's) exposure can be as long as 60 seconds, 4x longer than the S410's max exposure time of 15 seconds.
A proper comparison would have been ISO 100, same aperture, same shutter. THEN the images would have been comparable. EXP +2EV just tells the auto-exposure to be biased in that direction.
As I said in my post, there are two kinds of low-light shooting. One where you use a long exposure time (almost always requiring a tripod--judging from the motion blur that I see in your S410 image, I guess you didn't use a tripod here?), which allows you to kick the ISO down to 100. This is not very interesting, because most cameras perform very similarly in this scenario (again, using auto-exposure, your FH20 did not use a sufficiently long exposure time), and this scenario is not very practical, either, because your subject has to be motionless to avoid motion blur, and you have to extremely stable (usually requiring a tripod) to avoid motion blur--okay for shooting a figurine on a desk, but not good for capturing action at a bar or a concert, where your subject is in motion and you can't set up a tripod.
So when people talk about low-light, they are talking about the type of low-light where you have a relatively fast shutter, and you compensate by jacking up the ISO (and some optical image stabilization, which the S410 lacks, would help a lot too). It is when you jack up the ISO to something like 1600 or higher that you separate the men from the boys and the quality of the sensor becomes apparent. And in this department, the ZS6 would be far, far better than the S410 (which can't even go above 400) (but Fuji's EXR cameras are even better, at least among non-DSLRs, and of course, nothing beats a proper DSLR).
One more note about your pictures: Almost all the cameras I've seen do NOT have shutters that slow down to 1 second or longer when using auto-exposure. If you want the shutter to remain open for that long, you gotta manually tell the camera that. Low-ISO stabilized shots are almost always done in shutter-priority mode (the "S" or "Tv" on the dial) and not regular auto mode.