But what if you've already taken your photo, and it looks grey and dull as described above? Fortunately it is quite easy to fix this using image editing software, especially a good package such as Adobe Photoshop, Photoshop Elements or Corel Paint Shop Pro. The tool that can correct this problem is Levels, which is used to make fine adjustments to the brightness and contrast of an image. In Photoshop it can be found by using the keyboard shortcut CTRL + L, or in the Image > Adjustements menu.
The levels dialogue includes three buttons for setting various tone points in an image, one of which is used to set the white point. Simply click on this button, and then click on any part of the image that is supposed to be white. The program will then adjust the brightness histogram to make that point white, and in the process brighten up the whole image.
If you are feeling a bit more creative you can achieve much more accurate results, with usually less loss of detail, by manually adjusting the levels sliders. Move the left (black) slider to the right, and the right (white) slider to the left to equalise the histogram, then carefully adjust the mid-point slider to lighten or darken the image until the snow is mostly white but with some visible details.