The Finished Product: Reading the Histogram

Last lesson, we talked about the different types of metering that you can set your camera to. The different types of metering each have their own ways of calculating exposure which is then show by the light meter.

Knowing about the different types of metering is extremely critical in creating perfectly exposed photos. The different types of metering allow you to select different areas for exposure calculation thus giving you the flexibility to adjust accordingly.

Matrix, center-weighted, and spot metering are the three types that we discussed last time. We mentioned that the spot metering is pretty straight forward but complex at the same time since it calculates exposure in your focused area - something that can vary through aperture.

Center-weighted metering is the type of metering that selects the dark and light spots right in the middle of your view and averages it. Meanwhile, matrix is a much more complicated form of light metering wince it involves brightness, colors, contrast, and more factors.

Today we are, yet again, closing another chapter in this series of lessons by finishing off our discussion on exposure. What we will be discussing today is the finished image itself and how to actually read the light in it through the histogram.

Reading Light

The histogram is a tool in photography that was developed due to the advancement of camera technology. Since cameras are now run by sensors and data, modern DSLRs are now able to present you with the exposure information of your image.

This information is presented through the histogram which is a series of charts containing the data of your exposure. Reading the histogram can be quite difficult at the start but should be a convenient skill once you get the hang of it.

Reading the histogram is all about interpretation and knowing what the amounts indicate. Learning how to judge the exposure of an image through its histogram is very important in creating a well-balanced photo.

Once you have learned how to correctly interpret the histogram, you can easily pinpoint on what you need to tamper and adjust the amounts through your editing software. With that said, it is safe to say that the histogram is the most reliable way to look at your exposure.

The Histogram

The histogram is a powerful tool that most starting photographers fail to utilize in their early days. This set of charts is actually a visual representation of your image exposure so understanding it can spell the difference between a good and a bad finished product.

In order to use the histogram to your advantage, you have to learn how to read it. In technical terms, the histogram is actually a bar graph of frequency distribution. As you may or may not recall from your high school Chemistry class, light varies through frequency.

The histogram is then a graphical representation of how much pixels were exposed and to what extent did the light penetrate them. It involves three tones: black, white, and medium or your midtone.

The black tone in your histogram represents the shadows or the pixels that did not receive too much light during the shot. On the other hand, the white tones represent the highlights or the pixels which actually received a lot of light during the shot. The midtone are the perfectly-balanced pixels in your image.



As you can see in this picture, the histogram features a spectrum of your highlights and shadows or blacks and whites. The height of the shaded area represents the amount of the pixels in that region and the higher the graphical representation is, the more pixels. 

Just by looking at this black to white histogram, you can actually make the conclusion that the photo is quite underexposed. Basing on the height of the bar, you can see that a large number of pixels are black which means that the light did not hit them too much. 


Consequently, a photo that is overexposed will look like the total opposite of the image above. An overexposed photo will feature higher ratings on the right side of the spectrum indicating that there were more pixels receiving whiter tones.


Meanwhile, a well-balanced photo in terms of exposure should look something like this. As you can see, the dark and light tones are at the minimum while the medium tones have the most number of pixels.

As mentioned however, an image with a perfectly-balanced histogram isn’t necessarily a beautiful one. Exposure can be used in various ways and in some cases images are underexposed or overexposed for the better.

Histograms can also have spikes or gaps which shows a great variation in your image in terms of exposure. These gaps or spikes in your histogram are produced by a spot or two in your image that features a really different exposure as compared to its surroundings.

Conclusion

So today we learned the proper way of interpreting a histogram. We mentioned that the histogram is a powerful ally if used properly and understood well. We also defined the histogram as a visual representation of your image’s exposure.

Histograms feature a spectrum of black to white with midtone in the middle. The height of the bars in your histogram indicate the number of pixels shot at the corresponding tone which means that a taller shaded area means more pixels.

With that we are formally ending this section that features everything that you need to know for exposure. We hope that you learned a lot this section so feel free to share these articles to your peers to spread the knowledge!