How can I take a photo like the ones below? The problem is that my photos (taken with a bridge, Sony H2) will get blown up at the highlights. Is it because I'm using a weak camera? Is it because I'm shooting in JPG (can't use RAW)?
Is this dynamic range achieved by greater cameras + RAW? Or is it by post-processing?
Is there a pattern to this type of photos like: wide apperture (< f5.0), RAW, ...?
Examples:
That picture isn't taken with "natural lighting" -- there is a large "hot" reflector (probably a gold-toned or "zebra stripe" metallic type) to the left of the camera throwing light back into the subject.
Picture quality is rarely about the camera. It's about composition and lighting. Your camera may not be able to throw the background quite as far out of focus as the one used to take this picture, but if you make use of auxillary light sources (like the reflector used here) you can take pictures that are every bit as well-lit as this.
In addition to the reflector that Stan Rogers pointed out, one of the things that makes a huge difference is the time of day that you try a shot like this. Here in the northern US - this is a perfect time of the year to try shots like this. The sun is setting earlier in the evening, and the light becomes very soft, in addition to the great fall leave color.
In particular, you will want to try to do a portrait shot like this around 30mins before the actual sunset to provide you with the softest light. You could also give it a shot at sunrise, but that's just too early in the day for me :)
You can also throw back some light with an off camera flash (left of camera) using a warm gel (to match the color temp with ambient light). If you use E-TTL (or whatever Nikon calls the equivalent), you can simply back off of exposure compensation, and then push your flash compensation up.
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