In today’s wonderful world of digital, there are two helpful tools in our camera bodies to assist in making a good exposure – your in-camera exposure meter and your histogram. The LCD is very helpful too, but it can lead you astray if you’re not careful.
Exposing to the Right means that you are choosing an exposure for your shot that pushes more pixels up into the brighter tonal regions. Why? Because when you do that, you still retain ALL of your pixels in your shot. This is little trick could also be considered overexposing, or making your photo a little overexposed.
The histogram (as seen above) is what helps us push those pixels to the right. It’s broken down into four areas, from right to left. Those areas are: Highlights, Lights, Darks, and Shadows. The higher the graph in one particular region indicates that there is more information in that particular portion of the photograph.
Without getting too technical here, Exposing to the Right means that we are keeping that little graph (and most of the information in the photo) pushed to the right side of the histogram. Again, this is because when you overexpose all of the information is still there in the image file. When you underexpose, pixels are dropped from the file.
To see for yourself, go out and shoot a properly exposed shot, then set your camera to underexpose by 2 stops (ie f/4 to f/8) and then take the exact same shot. Copy both files onto your computer and look at the file sizes for each. The underexposed shot will have a smaller file size every single time, because there is less information in the file. If you still haven’t sipped the kool aid, shoot another properly exposed shot and then shoot an overexposed shot and you will see that both file sizes are almost the same size. All the information is still there!
So why is this important?
When doing any sort of post processing, you can still bring back information from an overexposed shot and it will be clean and retain detail a heck of a lot easier than you can an underexposed photo. So when you’re out shooting and you expose to the right, if you happen to overexpose “the shot” you can expect to save it in post and still have a great looking photo. Underexpose, and your shadow areas are going to be muddy and noisy – and you will have missed the opportunity to get a great photo of “the shot”.