As winter moves forward and the days continue to grow colder, outdoor photography is more and more likely to include snow. This will pose a problem for most cameras, either digital or film based.
A blanket of snow will play havoc with the metering system in your camera. Your camera will measure the brightness values in the scene you are shooting and adjust the exposure so that the resulting photograph has an average brightness of 18%. A large amount of snow will cause the camera to underexpose the image to accommodate for the extra amount of white and as a result, your snow will have an ugly grey cast to it.
If you camera has an exposure compensation mode (either on the dial or as a menu in the setup) it will be necessary to provide more exposure for the shot, usually between 1 and 2 stops.
In the photos below, the image on the left was shot with auto-exposure and no exposure compensation. The water has little to know detail and the snow is a dull gray. The second photo was shot with auto-exposure as well, with an exposure compensation of +1. The water begins to show more detail and the snow is becoming more white. The third image is also shot with auto-exposure, only this time with +2 stops exposure compensation. The water is well exposed and the snow is now more natural. In this example though, the snow has started to lose some of it’s texture. Exposure compensation of +1.5 stops would have given us a nice exposure on the snow while still retaining its texture.
Snow will reflect the colour of the sky and as such, may appear blue under open sky (as we see above) white (when shot on an overcast day, which will also show little or no texture in the snow) or may even take on a red or orange cast early in the morning or as the sun goes down. Trying to expose the snow to be pure white will most likely result in an overexposed image.
Next week I will discuss S-curves and diagonals in your photos!
The digital photography tip of the week is written by the PCIN Assistant Editor, Chris Empey. Chris is a long time photographer and is currently the vice-president of the Niagara Falls Camera Club. You can see more of his photography at his Photo of the Day website.
If you have a tip to send Chris, or a question about digital photography he can address in the newsletter, send it to firstname.lastname@example.org.