The histogram is a basic, simple but very useful tool that can be accessed both on your camera or via the software you use for post-processing of images. It is essentially about exposure.
A histogram can help identify if a picture is overexposed or underexposed. It’s no longer a guesswork (or rather a more accurate guesswork). By using the histogram, you can ensure that the colors and lights are well represented in your photo. The histogram does not come with rules, so for each photo, your histogram should and would naturally be different. There are a few tricks to it though and once you understand those, you would understand your pictures better.
Here are two distinct histograms to help illustrate the concept better:
Basically, the two patterns that would emerge from a histogram will be an “n” shape or a “u” shape.
A “u” shaped picture is likely to contain extremes and have contrast a lot. If it’s intentional it’s okay, if not, you might want to remedy that. Likewise, for the “n” you should look out that there is no washing out of colors, especially if the curve does not meet at one of the extremes. Why is it so?
The right extreme represents pure white and the left extreme represent pitch black.
So a scenery that had shadows and black objects in it but not showing an inclination to left extreme of the histogram suggest something is wrong. To better illustrate this, have a look at this beautiful night shot and notice how the histogram naturally inclines to the left extreme.
Here’s another shot, this one I took on a bright day. No dark spots or shadows, so it naturally inclines to the right.
Like I said earlier, there are no fixed rules. The histogram is a tool to help your photography not dictate it. It’s completely okay if some of your pictures have an inclination to both extremities like this very gorgeous photo by Vitaliy Lyubezhanin on Unsplash.
That’s it for histograms (to get started), don’t be afraid to experiment. That’s how each of us finds our own styles and most importantly that how we improve.