Fix Brightness and Color in GIMP

Fix Brightness and Color in GIMP

This post may contain affiliate links. Any sales made through such links will reward me a small commission at no extra cost for you.

I’ll be honest. I don’t always get great photos right out of my camera. Most of the time there are two problems I have to tackle with my photos. White balance (or color problems) and exposure (or brightness problems).

Lucky for me, White Balance and Exposure are both really easy to fix in a program like GIMP.

Anyway, since I usually have to correct these two problems, and I’ve seen these problems in a lot of photos on the internet, I thought I would give you the quick run down on how I tackle them. If you sell anything online (maybe you’re an Etsy seller looking to up your photography game?) this tutorial is for you!

The Problem:

white balance problems gimp
This picture of a necklace was taken on a white background, but it’s easy to see that this background isn’t white! With a little tweaking I can correct the blue tone of the photo and make the beads stand out against the background by adding some contrast.

How to Fix Color and Brightness in GIMP:

First, open up the problem picture in GIMP. To do that, just open GIMP and go to File > Open. Navigate through your computers files to find the photo you want to open, then click Open.

Now, follow along to Fix White Balance and Exposure problems fast!

Fix White Balance (color)

color balance tool for white balance problems GIMP

Like I said before, this picture is too blue so I’ll need to balance the blue out with more yellow, and even a bit of red. I’ll do that with the Color Balance Tool.

  • Go to Colors > Color Balance in the Main GIMP Menu Bar. The Color Balance Window will pop up.
  • Start with the MidTones option checked.
  • Adjust the Blue/Yellow slider to remove some blue, and add yellow. Then Adjust the Red/Cyan slider to add some Red, and take away some Cyan. (If your photo is too yellow or orange, do the opposite)
  • Now, check the Highlights option, and do the same thing.
  • Check the Shadow option, and repeat the process.
  • Go back and forth between the MidTones, Highlights, and Shadows, tweaking your adjustments until the colors are just right. Then click OK to apply the effect to your photo.

You may have to adjust the Magenta/Green slider a bit too to make your picture perfect.

So that’s problem number one solved. My picture no longer has that blue tint, but it’s still pretty dull. It’s bright enough, but there isn’t enough contrast. So, I’ll use a tool in GIMP called Curves to make the beads and the shadows a little bit darker against the white background. The contrast will make them really pop!

Use Curves to Fix Exposure/Contrast in GIMP

fix brightness and contrast in GIMP

  • Go to Colors > Curves in the Main GIMP Menu. The Curves window will pop up.

Let’s pause for a second to take a look at this window.

There’s a grid in the middle of the window with a diagonal line going across it. That line is adjustable, you can click anywhere on that diagonal line and drag up or down to make parts or your photo lighter or darker.

Drag up to make the photo lighter, drag down to make it darker. Where you click matters. The right side of the line controls highlights in the picture, the left side controls shadows, and the middle of the line controls mid tones.

Got that? Cool, here’s how we’ll use that line to fix this photo:

  • Click the highlight side (a box or two from the right edge) and drag up, just a little bit. The highlights of the photo will start to get brighter as you drag.
  • Now, the shadow side (a box or two from the left edge) and drag down a bit.
  • The shadows and mid tones of the picture will get darker as you make this adjustment, so you can tell how far you should drag.
  • Click OK to apply the effect when you’re happy.

That’s better!

I usually only click two points with Curves to make a nice smooth S curve. That keeps the line, and therefore my picture, nice and pretty.

Bonus: Levels to Whiten Whites

levels in gimp to whiten whites
If the whites of your photo aren’t quite white, but curves it making everything too bright, try this trick. It whitens whites better than bleach!

  • Go to Colors > Levels. The Levels window will pop up.
  • In the top section of this window, there’s a chart (AKA a histogram), and if you look closely you’ll see three little arrows underneath it.
  • Click on the arrow on the right side of the histogram, and drag it just a little to the left. As you drag the white parts of your photo will whiten without substantially brightening the rest of your picture.
  • Click OK to apply the effect

That’s It!

I ended up going back to do another Color Balance adjustment after I brightened my photo because I realized there was still some blue to remove. And that’s kind of the nature of photo editing. Sometimes you have to go back and tweak things.

I hope that helps!

Leave a Reply

Your email address will not be published. Required fields are marked *