I am struggling with this months assignment as I haven't done any high key photography before. Is the best way to get a high key photo to change the exposure compesation.
Leaving the camera on 'auto' will almost certainly result in under-exposure and a relatively dark image. Since auto always tries to achieve a balance between light and dark, when confronted by a mainly light toned HK subject (as the brief requires) the exposure system will always assume that it is a mixed-tone subject brilliantly lit and crank the aperture closed a couple of stops accordingly.
I've just been to the beach here in Sri Lanka and shot a load of frames using the exposure compensation dial on my G10 to fool around with the exposure. I eventually settled on +1 stop but with hindsight I reckon I could have gone a bit further. The trick is to try and pitch the exposure just right so that there are some small areas of 'proper' black to go with all the lighter tones. If there is no area of black (or near black) the result will be a bit grey, flat and soggy-looking. Equally you don't want the lightest tones to wash out and have no detail in them.. Tricky!
I too had never tried doing HK shots before so I'm pleased that Daisy has set us this task... requires a bit of head-scratching but there's no gain without pain!