What is Chromatic Aberration?

Photo in forest with chromatic aberration

Chromatic aberration is a color distortion on the image when different wavelengths of light are focused at different points.

To be clearer you will see this in an image with distorted colors and halo artifacts. You increase the chance to see it if you take a photo of something dark on a white or light background. Or vice versa. For example, if you take a shoot of a bulb of bright lamp in the dark.

For example, in the photo at the beginning of this post, specifically on the thinnest branches near the sky, you will see chromatic aberration. The thinnest branches seem to be purple instead of wood color.

More often you will notice it on wide-angle lenses. Particularly when shooting in low light conditions, when you open the aperture.

However, you can easily learn how to prevent and remove CA from your photos.

You can use photo editing apps to edit photos on which you see chromatic aberration. However, you can avoid shooting the widest angle of your lens or even closing the aperture, to make them appear weaker or invisible. In many cases, the better lens is equal to a lower chance of being prone to chromatic aberration.

But if you read our post till the end you will know how to deal with them no matter which lens or camera you have.

Table of Contents

What Causes Chromatic Aberration?

Chromatic aberration

Chromatic aberration appears because of the refraction. Simply, different wavelengths of light at different angles in a lens make refraction. It results that the light is focused at different points depending on its wavelength. And you get the distorted colors and halo artifacts.

Based on how CA occurs, you can see axial and lateral.

You will see axial when the wavelengths of light fail to converge at the same focal plane. In this case, you will see blurred edges and color fringing along the optical axis.

On the other hand, lateral occurs when different wavelengths of light have varying degrees of magnification at the edges of an image. The result is color fringing and blurring away from the image center.

In any case, both will decrease image quality, so you should be aware of that. And you should be prepared for how you can prevent or minimize this effect with the proper settings of your lens.

How to Avoid Chromatic Aberration?

Chromatic aberration - example

There are 3 options for how to reduce the chance to see chromatic aberration:

  • Option 1: To use high-quality lenses;
  • Option 2: To shoot at a narrow aperture;
  • Option 3: To avoid using a wide-angle lens (where possible).

Let’s start first with lenses. Usually, better (read more expensive) lenses are designed to be more resistant to chromatic aberration. And certainly, these lenses will produce sharper images and generally with less distortion.

However, if you don’t have an expensive lens you need to find out how to prevent them with your current setup.

The quickest option is to shoot at a narrower. When you open the aperture the light is focused more tightly on the image sensor. And you will avoid or significantly reduce it.

Another option is to not use a lens on its widest focal length. So, it means if you use a lens with a range, let’s say 18-105 mm, try to use 20-22 mm instead of 18 mm when you shoot wide-angle images. You will get just a bit narrower image but with less chance to get chromatic aberration.

How to Remove Chromatic Aberration?

However, the higher chance is that you will notice chromatic aberration when you see it on a bigger screen, instead of while you taking a photo.

In this case, you can correct it using photo editor software. Maybe you won’t completely eliminate them, but you can significantly reduce their appearance and negative effect on image color.

We will cover how to do so in Adobe Photoshop and Lightroom.

In Photoshop

If you prefer to use Photoshop you can easily reduce chromatic aberration using one of 2 ways. Actually, there are more ways to do so, but we choose them thinking the easiest methods to do so.

Option 1: Lens correction filter

Remove CA in Photoshop using lens correction filter

If you prefer to use Photoshop you can easily reduce it using the Lens Correction filter. Below is a step-by-step guide on how to do so:

  1. Open image in Photoshop;
  2. Duplicate the background layer and start editing on the duplicated layer (background copy);
  3. On the top navigation bar select the “Filter” menu and then choose “Lens Correction” filter;
  4. You can first try to use built-in profiles. If you find your camera or lens, you should apply it and see if you are satisfied with the results;
  5. Another option is to make custom adjustments. On the right panel choose “Custom” and then you will see 3 sliders to work with. You can adjust red/cyan, green/magenta, and blue/yellow fringes;
  6. When finished, click “OK” to save your changes.

As you see, the whole process is quick and straightforward even if you don’t have much experience in using Photoshop. Also, if you have RAW images instead of JPEG, always do so on RAW images, simply you will have more “space” to work on.

Option 2: Combination of blur & blending

Remove CA in Photoshop using blur and blending

Another solution is to combine the Gaussian blur filter and blending:

  1. Open image in Photoshop;
  2. Duplicate the background layer and start editing on the duplicated layer (background copy);
  3. Select the “Filter” menu from the top navigation bar and then select “Blur” from the drop-down menu;
  4. Choose “Gaussian Blur”
  5. Adjust the radius somewhere between 7 and 12 px (play with this until you find what works for your particular image);
  6. Then find the Layer menu on the right bottom, and change the blending mode from “Normal” to “Color”
  7. When finished, click “OK” to save your changes and apply them to the image.

After this, you will get rid of chromatic aberration, but maybe the other parts of the photo won’t look exactly how you wanted. We mean mainly on saturation. 

In cases where the overall saturation drop too much and you will need to make colors to be more vivid. Instead of just increasing it with the saturation tool on the layer you work on, you should make this change using a mask.

The quickest way is to add a “Mask” to the layer and make it inverted with the command CTRL+I (on Windows) or CMD+I (on Mac).  Then select “Brush tool” and choose “Soft brush”. Make sure the selected color is white, and fill in the parts of the photo where you don’t satisfied with saturation.

You see that this second method is not hard as well, however it requires a bit more steps, and maybe more play with it, but you will reduce or completely remove chromatic aberration.

In Lightroom

Remove CA in Lightroom using lens corrections tool

If you prefer using Lightroom in your photo editing workflow you can correct chromatic aberration as well. The easiest way is to use a lens correction tool. So, follow our guide below and get rid of it using this 5-step process:

  1. Import image to Lightroom;
  2. When you see the image in Library go to Develop module;
  3. On the right-hand side find “Lens corrections”;
  4. In profile find your camera/lens and tick “Remove Chromatic Aberration”;
  5. If you are not satisfied with the results of your camera profile, move to “Manual” and make adjustments in hues and amount manually.

However, if it isn’t corrected in the way you want, you can always switch back to Photoshop and edit your image in more ways.

Best Practices to avoid or minimize Chromatic Aberration

Remove chromatic aberration in Lightroom

Of course, the best option is to prepare yourself for minimizing chromatic aberration to save your valuable time in post-processing.

So, we want to introduce you to the best practices we apply in our photo shoots to minimize or completely avoid the negative effect of chromatic aberration.

Plan Your Photoshoots

The most essential thing in every aspect of photography is preparation. So, instead of thinking about how to correct chromatic aberration in post-processing, why don’t you plan how to avoid them?

There are a few things you should do before every photoshoot:

#1 Test your lenses

In different lighting conditions, focal lengths, and different apertures. See which you will end with visible CA on images and make a plan for how to avoid it.

#2 Make some trade-offs

If you already have high-quality (read: expensive) lenses the chance is that you won’t be mobile as you have a lighter setup. This is especially important while you traveling. 

In other words, maybe your “backup setup” with an all-rounder lens will be enough good in most situations. Simply, consider the size and weight of the whole setup (camera + lenses) before you decide that you need ALL your expensive lenses to be with you on your next weekend trip.

Think... Then Take Photo

It sounds simpler than it is. But you simply need to think before you take a photo. We mean about small tweaks you can do upfront which will save you a lot of time in the post-processing.

If you know that the lens you use is more prone to chromatic aberration at the widest angle, think about shooting with a 5-10% narrower angle. Let’s say your lens has a lot of CA at 18 mm, try shooting wide angles at 20 mm instead.

The angle will not be dramatically narrower. To be honest you probably won’t catch the difference. But you will save a lot of time in editing later.

The same is when you think about the aperture. Maybe you don’t need always to use f/1.8 to get great bokeh every time. If a narrower aperture gives you an image without chromatic aberration, the bokeh you will get is probably almost the same.

In a case when you are forced to take photos in conditions where you can’t avoid chromatic aberration, be sure you shoot in RAW. If you have RAW images, you will be more flexible to edit them later.

Master Photo Editing Apps

You should master your preferred photo editing app, not only to remove unwanted CA. But also to be sure that you don’t provoke “artificial” CA in post-processing.

We mostly think about making drastic adjustments to the color or hue. Because this can cause chromatic aberration to appear.

Also if you do make sharpening, pay attention if it won’t add chromatic aberration to your images. In other words, to make minor CA appear more visible.

Conclusion

When you come to our conclusion, we are sure you clarify a lot of things regarding chromatic aberration.

This could be a serious issue for photographers, because of its artifacts and distortions in the colors of the photo. But fortunately, it’s easy to correct, or prevent it, if you know your camera and lens setup.

The best way to prevent chromatic aberration prevent it is by using a high-quality lens. Because these lenses are designed to be more resistant and will produce sharper images with less distortion. Also if you shoot on the widest angle your lens will be probably more prone to chromatic aberration. 

On the other hand, if you take photos at a narrower aperture it will also help reduce chromatic aberration as the light is focused more tightly on the image sensor.

By keeping all these things in mind, you can minimize the negative effect of CA on your photos.

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