The Nikon Coolpix S30 is so simplified that there are no controls for much of anything, including ISO and white balance, which made it difficult to do our lab testing. However, here are two 100 percent crops from our test scene, one at ISO 80, the other at ISO 400. The ISO 400 shot is darker because there is less light, but you can see the amount of noise and loss of detail. ISO 400 is typically the starting point for what the camera selects when shooting indoors with good lighting. The camera goes up to ISO 1600, but the results only get worse. Basically, the S30 is fine for outdoor use, but I would not recommend it for regularly shooting indoors or in low light.
If you like to shoot closeups, the S30 can focus as close as 2 inches from a subject. As long as you have a lot of light, the results are usable at larger sizes if you want to get a closer look at details. This is a 100 percent crop of the inset photo.
There is some slight barrel distortion at the wide end of the lens (top), but everything looks good at the telephoto end (bottom). I did see some fringing in high-contrast areas, but nothing too horrible, and given the camera's price, it's an acceptable amount that's only really visible when photos are viewed at larger sizes.
The S30 survived its underwater testing: three 60-minute dives in 2 feet of water (though it can go down to 9.8 feet). Photo quality is good enough for casual snapshots as long as you have plenty of light and clear water. My water had a little bit of sand in it, which is why these shots look somewhat hazy, but I would expect it to be better in a pool.