rajfotografie

What is a histogram?

Many cameras and photo editing programs display a histogram that shows the exposure and color distribution of an image.

Bar chart

A histogram is a graph made up of bars. On the x-axis are the brightness values, ranging from dark (left) to light (right). On the y-axis you see how often each brightness value occurs. This gives you a quick overview of the exposure and color intensity (RGB) in your photo.

Proper exposure

In a well-exposed photo, the bars are fairly evenly distributed across the histogram. This is often referred to as a normal distribution.

Underexposed or overexposed?

If the image is underexposed, most bars will be on the left side. If it is overexposed, most bars will be on the right.

Camera histogram

Many cameras display a histogram on the screen after taking a photo. Below are some examples.

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Histogram in Lightroom

Lightroom combines exposure and color information into one histogram. Overexposed and underexposed areas are clearly visible and can often be corrected.

RAW image edited histogram

After editing, the histogram shows more midtones and a better-balanced exposure.

How do you use a histogram?

Even if a photo looks good on your screen, it’s wise to check the histogram. It quickly shows if there are exposure problems.

If needed, adjust the exposure using aperture, shutter speed, or ISO.

Exposure compensation

The +/- button allows you to quickly adjust exposure. Each step increases or decreases the exposure.

Take a few shots and check whether the histogram improves.

Keep in mind: at night, a dark histogram is often normal and intentional.

Highlight warning

Many cameras show blinking warnings when highlights are overexposed. These areas are difficult to recover, especially in JPEG images.

Active D-Lighting

This feature helps improve shadows and highlights in high-contrast scenes, resulting in a more balanced histogram.

Histogram in post-processing

Every adjustment you make affects the histogram. You can directly influence shadows and highlights by adjusting sliders.

Working with levels

In Photoshop, the histogram ranges from 0 (black) to 255 (white). This allows precise control of brightness and contrast.

By selecting RGB, you can adjust each color channel individually to correct exposure and color casts.

Example result: