Exposing to the right
First off we need to learn about the camera’s histogram and what it represents. “The Histogram is a tonal representation of the dynamic range within an image”, at least that is what Wikipedia says. In simpler terms it is a graphic representation of the image you took. The histogram shows all of the data within the photo.When looking at your histogram, keep in mind the left side represents the shadows (Blacks/darks) and the right side represents the highlights (brights/whites) .Why is this important? If you overexpose the image like the image below,, all of your highlight information is gone, it is unrecoverable.
•Find the button on your camera that looks like this [+/-] This is the Exposure Compensation button.
•The exposure compensation button can be used when your camera is in any Creative Exposure Mode. For example, you can use it while the mode dial is on P (for program), S (Nikon shutter priority), TV (Canon shutter priority), A or AV (aperture priority) modes.•Take your initial exposure, look at your histogram and adjust based on that information.•Hold the +/- button down while turning the main dial. (usually located by the shutter button)
______________________So, lets say your histogram looks like this, the image is “Underexposed”
You want to expose longer to fill that histogram and get the data as close to the right without touching the right side.The histogram is broken up into 5 sections. This is how I gauge how much compensation to add. In this case, the under exposed histogram above would appear to be near 2 stops underexposed.
I would then add +1.5 stops holding in the Exposure Compensation Button and moving the shutter speed dial until the top LCD shows +1.5.Now take another image and watch the histogram. You should be very close if not right on. By exposing to the right you are ensuring that you get the most data from that scene without over exposing.If you “over expose” like the image seen below, simply add negative exposure compensation and shoot again.You may be thrown off with how light the image looks when reviewing in Camera. This is Okay, you will have more leeway to make adjustments when you post process the file, especially if you are shooting in RAW.
Another thing to keep in mind is that your histogram will look different from scene to scene but this is a good starting point.
for instance a scene shot in heavy fog may yeild a single spike of data in the middle of the histogram. there isn’t much of anything you can do about it in a situation like that, which is Okay. The reason for this is, there are no highlights and there are no shadows in the scene.
The same thing goes with taking a picture of a pile of coal, the histogram is going to be pushed very far to the left, simply because there are no highlights in the scene.
After some simple photoshop tweaks, you should end up with a nice, clean image.
For more detailed information on exposing to the right, visit HERE