I ran across this thread and thought I would respond to the exposure problem with your pictures. I don't think you have a camera problem (especially with the S50 - it's a good camera). I think a lot of it has to do with the angle some of the shots were taken in combination with the position of the sun. It's not an all out backlighting problem, but it's pretty close. When you point you camera at a scene, the metoring sensors are looking at the overall tonality of the scene (areas of light to areas of dark) and the camera is trying to come up with an exposure that is close to normal (what's refered to as 18% gray). If there are areas in a scene that have both extremes, it is going to expose for one or the other. In this case, it exposed for the areas that were in the shade leaving the sky overexposed. You can correct this by changing the angle you shoot, but you can't always controll where your subject is. In that case, I would suggest a gradient filter you can attach to your lens. The filter is a dark gray to clear. You simply position the dark gray portion of filter where the bright areas are (the sky) and the clear portion where the normal to dark areas are. Your camera will then see this as an evenly lit scene. Sorry this is so long - hope it helps!
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