How To Adjust the Exposure in GIMP

Photo by Paul IJsendoorn

One of the first steps in your editing workflow should be adjusting the Exposure. That is if you didn’t nail it in-camera! Today you’re going to discover how to use the Exposure adjustment tool in GIMP, with pro results!

First, you’ll learn the basics of the Exposure tool. Then, I’ll share some pro tips for spectacular results. If you’re ready… let’s do it!

What is Exposure?

“Exposure is how bright or dark your image is.”

This photo is loaded with detail in the entire tonal range. Although it may not look like it, the Histogram tells me so!

Ideally, you want a well-balanced exposure in all parts of the tonal range; Shadows, Highlights, and Mid Tones. Doing so will reveal rich detail within the entire tonal range.

This, of course, is based on your creative vision for the final edit. It’s always good to start with a clean, classic type of edit before customizing it for your vision. This way, you start with the highest quality photograph possible. Then, you can pick and choose which detail to keep.

The GIMP Exposure Tool

To activate the Exposure tool in GIMP, go to, Colors > Exposure to reveal the tool in a new window. The two main options are; Black level + Exposure.

Black Level

This option allows you to change the Black point. In essence, this adjustment will increase or decrease the contrast in your photos.

Exposure

This slider will increase or decrease the brightness of your image. The adjustments can be made in 1 stop increments. A “Stop” is a term used by photographers to describe the amount of light captured based on three different camera settings; Aperture, Shutter Speed, and ISO.

Let’s say you underexposed your photo by 1 stop. If so, you can adjust the brightness by a 1 stop increase to balance the light.

Pro Tips For Photo Editing With the Exposure Tool

Using the tool is self-explanatory. Adjusting either slider to the left or right results in an adjustment. Then, change according to your personal preference. However, to get the best results from this tool, check out the following three pro tips…

ONE

You do not need to know how many “stops” are required to increase or decrease a photo’s brightness. Instead, I’d recommend learning how to read your Histogram to guide you in editing! Using a Histogram in conjunction with this tool will help you avoid over-editing… resulting in a loss of detail.

The “before” image has the correct exposure. The “after” image is over-edited and resulted in the highlights being overexposed… and destroyed the detail in that tone range. Using a Histogram helped me avoid this. F.Y.I., I intentionally edited this image to be too yellow in the highlights and blue in the shadows. It gives it a retro look. Which is the creative vision I had for this shot.

TWO

The Exposure tool applies a global edit. In other words, it will affect your entire photo. This can cause issues if different parts of your photos are well balanced. Let’s look at an example.

Adjusting her face’s brightness (with this tool) to make it brighter will result in other parts of the image becoming even more overexposed.

The “before” image received a global edit and the shirt is now more overexposed than before. The “after” image shows the results of using a Layer Mask to control where the edit is applied. In this case, only the face is brighter. Compare to the image above.

THREE

Since the Exposure tool is a global type of edit, you may want to seek an alternative. One possible solution would be the Highlight/Shadow tool, which will specifically target, well, the Highlights and Shadows of a photo.

What's Next?

In GIMP, you have a lot of tools for fixing your images. Knowing which one to use and why is half the battle for achieving your creative vision. Even though I offered some pro tips with different solutions, they might not be the right choice for YOUR photo (s).

For example, when you have both over and underexposed images, a tool like the Dodge and Burn tool might be a better option.

So, how do you know which tool to use and when?

First, you have to learn how each tool in GIMP works, its strengths, and its weaknesses. Throughout this article, I’ve provided several links to different GIMP tutorials discussing various editing tools. If you haven’t done so already, follow each link in this article to elevate your GIMP skills.

Or check out a collection of GIMP articles here. To elevate your GIMP skills even faster, check out these pro tutorials.

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Hello! My name is Chris Parker and I run this place. But, more importantly, what’s in it for you? Well, my passion is to help you achieve your creative vision.

With 30 years experience I believe I can help you do just that. So, if you’re ready… let’s do it!