Strange Artifacts in LR 4.1

[CJL]

I've recently started to notice some strange artifacts appearing in my files when processing them in LR 4.1  Here's one example:




The strange outline around the branches on this tree only appear when I select the canned "Camera Landscape" option as the camera calibration profile - no other adjustment I've tried seems to affect this, but it goes away as soon as I change to any other calibration profile.  I tried resetting all adjustment parameters, but as soon as I chose that calibration profile the artifact reappeared.

I'm running the latest version of LightRoom 4.1, on an iMac with a 3.4 GHZ quad-core i7 processor, 8 GB of RAM, a SSD, and am running OS X 10.6.8.  This image is from a Canon EOS 5D Mark III RAW file.  Here's the original image for reference:



I've also discovered the same artifact on some older EOS 1Ds Mark III RAW files, but in those examples the only setting that would affect the artifact is the white balance - if I set it to anything other than "As Shot" the artifact would appear, and as soon as I reverted back to the "As Shot" colour balance the artifact would disappear.  I have not tried printing any of the affected images to see if the artifact persists.

Any ideas as to what might be causing this strange phenomenon?

[Schewe]

Any ideas as to what might be causing this strange phenomenon?

You have the Defringe controls set wrong in the Lens Corrections panel in the Color subpanel. You are seeing the attempt at removing blue fringe and it's eating away the color in the sky.

[CJL]

You have the Defringe controls set wrong in the Lens Corrections panel in the Color subpanel. You are seeing the attempt at removing blue fringe and it's eating away the color in the sky.

Thank you!

I was certain I had reset everything, but didn't have that panel open so I must have missed it.