The Histogram Explained: Using a Histogram & What it Means
One of the most valuable tools, but perhaps one of the most misunderstood, is your camera’s histogram. Histo-what? We aren’t talking about Instagram’s cousin here. If you’ve been confused by that fancy chart they call a histogram, you’re in the right place! In this tutorial, we will break down using a histogram so you understand what your histogram is saying and how to use the information it provides to get the exposure you’re looking for. Finally, your histogram explained!
What is a Histogram?
The histogram helps you understand how light is distributed in an image. It is a graph that shows the distribution of pixels in an image, with the shadows are represented on the left, the highlights on the right, and the midtones in the middle. The height of any of the points on the graph indicates the number of pixels in that particular tone. Wondering where to view the histogram? You can choose to have the histogram appear on your camera’s LCD screen during your image playback. Consult your camera manual to find this function, as all cameras have different menus, interfaces, and settings. You can also view the histogram for your images in your editing software, like Lightroom or Photoshop.
What Does the Histogram Mean?
The histogram simply tells you what tones are represented in your image, and can guide you in making decisions in your exposure and processing. When your histogram has information climbing up on one side or another, it means that there are pixels in your photo that are either completely underexposed/black (on the left) or overexposed/white (on the right). In the chart above, we could assume that this was a histogram of a well exposed image, because there is a nice ranges of tone represented in the image, without a lot of extreme shadows falling off to the left or extreme highlights falling off to the right.
Because they are simply a representation of information, there are not “good” or “bad” histograms, unless the entire histogram is bunched up and spilling up all the way on one side. This would be representative of a completely underexposed or overexposed image. Traditionally, a well exposed image will reach from one side of the histogram to the other, peaking in the middle, and without falling completely off of either side, as in the example above. However, this does not apply in every situation, and certainly can be relative to your artistic goals. We will discuss this more in a moment.
First, let’s take a closer look at what the histogram is telling us. Here is the histogram for this image taken on the beach.
You can see that the histogram for this image spreads pretty evenly from left to right, with some peaking falling off on the right hand side. That tells us that in this photo, there are a tones represented from dark to light, with some true white pixels (or over exposure) in the image. In this case, the blown out sky is why you see some of the information climbing up on the right hand side.
Click Here to find out more about Cole’s exclusive new photography education community, Cole’s Clique, & unlock the entire course catalog for just $1!
Here is another example where again we see that the histogram is spread pretty evenly across all tones from shadows to highlights, except this time you won’t see the peak for blown out highlights on the right side.
Remember, we said that histograms, while helpful, can be relative. Some images do not follow an even distribution at all. Take a look at the histogram for this image below. You can see that it pushes almost completely to the left hand side, with virtually no information represented on the right. While technically, this is an underexposed photo, it’s range of shadows are what generate the artistic impact of the image.
Now take a look at this histogram. The majority of the information is pushed to the right hand side, because the image has mostly lighter, white tones. You can see that very little information in represented on the left side of the histogram, meaning there are very few shadows in this image.
Neither of these histograms follow the balanced curve “rule,” but both are nice images, with their artistic value being found in the intentional use of black and white tones. This reiterates the point that, while the histogram is a valuable tool for examining and evaluating the tones in your photos, it will likely vary greatly from image to image, based on what you are shooting and your artistic goals. Think of the histogram as a guide for obtaining the type of exposure you are looking for, and not as an indicator of a good or bad photo.
Think of the histogram as a guide for obtaining the type of exposure you are looking for, and not as an indicator of a good or bad photo.
Your histogram is a valuable tool that can really make a difference in gaining the type of exposure you are looking for in your images. Hopefully this helps you to better understand what your histogram is and how to read it to better interpret your photos!