Does Your Lens Have Color Fringing/Chromatic Aberrations?

August 26th, 2013

Several of the PFRE photographer of the month contest entries for August had some very noticeable color fringing (also called chromatic aberration) so I thought it would be useful to do a post on the subject.

Chromatic aberration comes from lens imperfections and is frequently present on wide angle lenses that don’t have the newer coating, so depending on what lenses you have you may have never seen it or it many be in many of your photos and you just expect it because it’s always there. I know about the subject mostly because I have a Sigma 8mm Fisheye, that I’ve used for 360s, that has serious chromatic aberration.

There’s a classic description of the subject by Tom Hogarty, leader of the Adobe Lightroom Team. This piece by Tom is over a year old, but I don’t believe much has been changed since then in Lightroom/ACR regarding chromatic aberration.

If you’ve got a lens that has chromatic aberration getting rid of the resulting color fringing is usually a simple matter of just turning on the “Remove Chromatic Aberration” check box in the Lens Correction panel of Lightroom. The tutorial above by Gregory Cazillo shows some additional fine points of removing CA.

It’s possible to use the Set Default Settings… command in the Lightroom Develop command to set the Remove Chromatic Aberration checkbox as the default or as several commentators on a recent post pointed out, create a preset that turns on the CA check box and does a series of other basic adjustments you do for all the images in a shoot.

Share this

8 Responses to “Does Your Lens Have Color Fringing/Chromatic Aberrations?”

  • Good post as usual. However one correction. Chromatic aberration is not caused by lens imperfections, it is caused by the physics of light. Light passing through transparent materials is bent based on its energy level (color). Higher energy levels (violet) are deflected less than lower levels (red). Chromatic aberration can be reduced by using different materials and to some degree design. Coating do improve lens in many ways, but do not greatly affect chromatic aberration. However, lens with better designs and materials also tend to be lens that have better coatings. So that may be the source of the confusion.

  • It’s also helpful to know the difference between CA & fringe. There are two distinct types of CA: transverse and longitudinal. When photographers say CA, they are generally referring to transverse CA, whereas fringe is longitudinal CA.

    When it comes right down to it, you only need to know that Lightroom handles these two types of CA with different functions. Transverse (red/green or blue/yellow) is handled with the “remove chromatic aberration” box, and longitudinal (purple/green) is handled with “defringe” tool. If you don’t see any purple/green aberrations, then just use the checkbox. But if you DO see purple/green aberration, use either the eyedropper or slider to remove them. Just checking the box WON’T remove purple/green fringe. Trust me, I made that mistake plenty of times when starting with LR.

  • I just realized that Larry’s link to Tom Hogarty’s article said pretty much the same thing as my comment, but obviously more detailed. Oh well, doesn’t hurt to reiterate!

  • Good information, thanks for sharing the technical aspects of CA.

  • What about fixes in CS4 Photoshop? All of you refer to LR for the fix. If the CA and Fringe fixes are in CS4, under what menu item ?
    Thanks
    Peter

  • @Peter- google “fix chromatic aberration in photoshop cs4” and you’ll get a ton of details on how to do it in CS4.

  • I switched to a Sony NEX-7 for outdoor pics because it has built-in chromatic aberration correction, and it does an amazing job! Not even a spec of it. In both PSCC and LR5, as well as Oloneo and Photomatix, I can still see traces of it.

    If you combine the automatic chromatic aberration correction with in-camera HDR (with the contrast and saturation slightly turned down), the NEX-7 yields amazing results. (16mm lens with the wide-angle attachment)

    It beats the heck out of my 50D for daylight shots… but…

    chromatic aberration in a dusk shot is far more tricky to combat.

  • It is my understanding that CA is a greater problem when the lens is fully opened, at the widest f-stop, 2.8 and lower. The smaller the opening, the problem is not as severe and can even be non-existent. Also, one can adjust any fringing (CA) in PS under Filter > Lens correction.

Trackback URI Comments RSS

Leave a Reply