Hi Jan and Oscar,
Why is it that the chromatic abberation on the d800e result is so much worse than with the d800?
Because it is not CA, but demosaic residue. False edge colors due to the higher acutance between individual sensels which do not have equal colorfilters. It should only happen because these files were created without any color noise reduction.
Yes, that's my conclusion as well. This is clearly not caused by classic chromatic aberration due to the lens. If you magnify the edges of the images from both the D800 and the D800E (in PS at highest zoom level), you can see a repeating pattern of red fringing in the D800 image, which is not present in the D800 image. Although the Imatest CA module was not specifically designed to analyze such false-color artifacts, I included the CA charts because I believe they may prove useful in testing the effectiveness of various demosaic algorithms. I also agree that, at least for the slant-edge portions of this chart, the false colors could be easily removed by applying color noise reduction (or CA reduction) methods (especially if applied during raw conversion).
However, I am not yet convinced that any of the tools intended to correct such failures of the Bayer CFA demosaic process (including the new moire removal tools in Lightroom, ACR and Capture NX2) will completely eliminate this issue in all cases.
As a side note, it's often been stated that nature and landscape photographers do not need to worry about artifacts caused by the absence of an effective OLP or AA filter on the sensor. But there are a class of subjects that I have not seen mentioned yet, where it can definitely be an issue. One of my photographic interests is astrophotography, both star trails and guided (on an equatorial mount) fixed images of star fields. Such images are best captured at relatively wide apertures using sharp lenses, under the best possible atmospheric “seeing conditions”. Due to the inherently small PSF (or Line Spread Function (LSF) in the case of star trails), the star images (Airy-disks) projected on the sensor may not cover enough elements in the Bayer array to allow proper color rendering, resulting in stars or trails with randomly-distributed false colors.
(Hey, why are all the stars in this image red, green or blue, with twice as many green stars as red or blue?!
---yes, I know that most of the stars won't be rendered pure R, G or B.)
So why not just apply color correction in pp? Part of the appeal of celestial images are the subtle natural colors of the stars and planets. The false-color correction routines I've seen to date also damage these natural color tones This is more than conjecture; I've seen it in my own images and a number of examples online. My current D700 is fairly immune, due to the relatively strong AA filter. But my old D70 (weaker AA filter) did have this issue. One common way to avoid this is to slightly defocus the star images. But this causes loss of the dimmer stars.
Those who like to shoot night scenes involving distant city lights (or any small specular highlight), may also experience this problem.
The high sampling density of the D800/D800E sensor should reduce the occurrence of the above issues. But it is one more thing to be aware of when choosing correct camera.