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What Is Chromatic Aberration?
Chromatic aberration goes by several different names. You may also know it as color fringing or purple fringing. Chromatic aberration is a type of optical problem that happens when the lens of your camera is unable to match all wavelengths of color to the necessary focal plane or when the wavelengths of color are focused at improper positions in the focal plane.
So, what causes chromatic aberration? This optical issue is caused by something known as lens dispersion. This happens when different colors of light travel at various speeds while passing through the lens of your camera. The result is that your image will appear blurred or that there will be noticeable colors around the edges, most often purple and green. This almost always occurs in high-contrast situations.
With a proper lens, all wavelengths will be focused on a single focal point. However, issues with a camera lens can cause chromatic aberration, of which there are two types.
Longitudinal Chromatic Aberration
Longitudinal chromatic aberration is also known as bokeh fringing. This type of issue occurs when different wavelengths of color don’t converge at the proper point upon passing through your camera lens. This type of chromatic aberration usually results in fringing around objects. You’ll notice red or green or blue, or a combination of all three, around objects in your picture.
The best way to negate longitudinal chromatic aberration is by stopping down the lens. The lenses that suffer the most from this type of chromatic aberration are fast aperture prime lenses.
Even with some of the most expensive lenses, you can experience longitudinal chromatic aberration. It often appears with fuzzy green coloring at one end of the image and a purplish hue at the other end of the image, with the proper neutral color in the center. This type of issue can usually be fixed during post processing.
By using the de-fringe tool, certain fringe colors can be corrected and even eliminated.
Lateral Chromatic Aberration
Lateral chromatic aberration is alternatively known as transverse chromatic aberration. This happens when different wavelengths of color being pushed through the lens at an angle end up focusing at different positions along the focal plane. This type of chromatic aberration almost never appears in the center of the image and can only be seen at the corners of your pictures in the most high-contrast areas.
With lateral chromatic aberration, blue and purple fringing is common. You also might experience some fisheye effect when using lower quality lenses. One of the only ways to get rid of lateral chromatic aberration is to remove or reduce the effects in post processing.
Is Chromatic Aberration Common?
Unfortunately, chromatic aberration is very common. Both types are common and sometimes even occur simultaneously. In a lot of cases, the only way to fix chromatic aberration is by using software such as Lightroom or Photoshop during post processing.
Modern lens manufacturers are trying to get rid of chromatic aberration once and for all using extra-low dispersion elements and high-tech optical designs. But this issue continues to this day, and it’s especially noticeable when using prime or zoom lenses. Sometimes, there’s nothing you can do except learn to deal with chromatic aberration.
The good thing about purchasing an expensive DSLR camera is that many of them come included with in-camera post processing technology that can reduce or eliminate chromatic aberrations without you needing to put in much work.
How to Prevent Chromatic Aberration
The best way not to deal with chromatic aberration is to prevent it before it ever happens. Some of the easiest ways to never suffer from photographs marred by chromatic aberration are to shoot using only high-quality lenses, to avoid wide-angle lenses at all costs, and if you can, shoot at the narrowest aperture possible.
The best way to prevent chromatic aberration is to shoot photographs correctly with your camera.
Shooting at a narrower aperture with a higher f-stop will help avoid color distortion. This is especially true when you have a poor-quality lens. If your lens isn’t very good and you’re shooting wide open at an aperture of 1.8, the chances of experiencing chromatic aberration are increased dramatically.
If you use the same poor-quality lens but narrow the aperture down to something like 5.6, it’s much less likely that the chromatic aberration will affect your photos. You can also try turning up the ISO, using flash where necessary, and slowing your shutter speed so that you don’t lose any light.
Another option is to optimize your focal plane. Color fringing happens more often with wide-angle lenses because they suffer from shorter focal lengths. If you’re shooting at only 18mm, you’re much more likely to spot chromatic aberrations because you’re taking photographs using the edges of your lens glass.
A better way to shoot would be to use a medium focal length of up to 30mm. This focal length can be used for lenses between 18mm and 55mm.
The last method we would suggest for preventing chromatic aberration is to shoot your images in RAW. But to be quite honest, if you want to be a professional photographer, you should never even think about shooting in JPEG. The only way to properly edit your images is by shooting them in RAW.
Raw pictures will store more data and work better in applications like Lightroom. Lightroom will almost always remove chromatic aberration from a RAW image. But a JPEG image is a whole different story. If you’re scared of chromatic aberration, always shoot in RAW.
Use Chromatic Aberration to Enhance Photos
Chromatic aberration can be used to enhance both videos and photos using applications like Photoshop. By taking a completely ordinary photograph and then separating the red, green, and blue channels, you can play with color fringing yourself to add an effect of unsteadiness to any image.
In fact, chromatic aberration can be used smartly to give a picture a 3D quality or a retro feel. Chromatic aberration can be used to make any picture appear psychedelic or trippy. This is definitely a great tool when editing photos.
How Do You Fix Chromatic Aberration in Lightroom?
If you absolutely need to fix chromatic aberration in some of your photos, the best tool to do it with is Lightroom. Once you figure out the appropriate boxes to click and the right settings in the application, you can easily remove all chromatic aberration from your pictures completely stress-free. Not only that, but Lightroom can help to fix things like barrel distortion vignetting as well.
To fix chromatic aberration in Lightroom, follow these easy steps.
Step 1: First you need to locate the lens corrections panel inside of the app’s develop module. The lens corrections panel is between the detail panel and the effects panel.
Step 2: Once inside the lens corrections panel, you’ll see four important sections. You have basic, profile, color, and lastly, manual. Start in the basic tab and select the top two boxes. Enable profile connections and remove chromatic aberration. The software is already equipped with profiles from almost every major camera manufacturer and lens manufacturer to quickly erase chromatic aberration.
The instant you enable both options, you’ll see the image change and most distortion will be corrected automatically. You’ll also notice the purple fringing will either be corrected or greatly reduced.
Step 3: Move on to the profile tab. You want to check “enable profile corrections”. You also want to make sure that Lightroom already recognized the make and model of your lens. If Lightroom has not recognized your lens, you can easily browse the options and select your lens manually. If your lens is not anywhere to be found, you may have to correct distortion yourself by using the sliders for vignetting and distortion.
Step 4: The last step is the color section. Select the box for “remove chromatic aberration” and you’re finished. This is almost always the only thing you need to do. Simply click the box and your image will be fixed.
Unfortunately, some images may have been so seriously affected by chromatic aberration that you need to do a bit of extra work to get rid of the distortion. In this case, move the sliders for purple hue and green hue until the fringes on your image vanish. You can also use the eyedropper to select the annoying fringes in your image to be corrected more accurately by the application.
Final Thoughts
Chromatic aberration is a type of color distortion that creates outlines of color along the edges of the objects in your photographs. It almost always occurs along metallic surfaces where there is the highest contrast between light and dark. This is because of a camera lens that fails to focus each different wavelength of color to the same focal point. And unfortunately, there aren’t a lot of ways to fix it.
You can use Lightroom or Photoshop, or you can try to avoid color fringing before it ever happens by optimizing your focal plane or shooting at a narrower aperture. But sometimes, chromatic aberration is just one of those annoying aspects of photography that professionals and amateurs have to deal with.
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