METERINGWhen photographing snow, any of the camera's matrix light meter modes may be used effectively. It really just depends on the overall scene. If the scene is evenly lit and has an even brightness, then center-weighted metering will work well to give you a good overall exposure.
Center-weighted metering averages the exposure for the entire metering area: By putting greater emphasis on the center zone, it reads overall brightness. Spot and partial metering work well with subjects that have more contrast. These modes let you meter only a small part of the scene. I find this metering most useful, so it's my preferred mode.
Spot metering is the most selective option, as it only reads exposure information from the single exposure zone in the center of the frame. This is approximately 3% of the total picture area.
Partial metering is similar to spot metering, but covers a slightly larger area. It only reads the cross-shaped central five metering zones, which is approximately 10% of the total picture area.
What makes a snow-filled photo most interesting is the rich detail and texture of the snow. While in the field, be sure to examine the histogram to help determine your best settings. Adjust your exposure (shutter speed and/or aperture) to reduce the amount of clipped whites. You can check the histogram on your camera's LCD screen.
Even when the camera "accurately" determines the correct exposure using the metering mode of your preference, with a subject like snow, you'll often see underexposed results. If this happens, use exposure compensation to deliberately lighten your pictures.