Relative to the synthetic image, Lightroom was, as expected, very close to the theoretical values for the GretagMacbeth chart. Versus a real image however, it shows significant differences, most noticeably in the red patch, where it has significantly more blue and green than might be expected. At first sight, this is a somewhat counter-intuitive result, as while the greater levels of green and blue indicate a more saturated color than the theoretical representation; Lightroom in general has a reputation for excessive red. It’s only in the green patch that there is significant excess red. This would imply that when the complaint of Lightroom’s “excessive red” is made, it is probably more of a complaint about the saturation of reds in the image, rather than an excess of the red color component.
Aperture shows no clear pattern of greater or lesser overall saturation, but does show two interesting characteristics. Firstly, the green components are still very much less than are the case for Lightroom, but at the same time the absolute variation from the theoretical value is far less – versus the synthetic image, the variation was -15.3, but against the actual it is only -6.3. This suggests that the Aperture calibration for the green components in a real image is probably better than Lightroom’s, even though the Lightroom’s better matches the synthetic image . Secondly however there are significant variations in the blue component, especially in the 1.1 profile. The newer 2.0 and DNG profiles show color rendition that is a lot closer to expected values that the previous version. This is consistent with Apple’s statements that the raw conversion subsystem has been substantially revised and improved in the new version. Overall, the actual M8 inages converted with the Aperture 2.0 profile is a better match to theoretical values than either the previous version of Aperture, or Lightroom.
Turning to Capture One, the most significant feature of the charts is the absence of “negative spikes” – while both Lightroom and Aperture have at least some color patches where at least one color is significantly less than the theoretical value, Capture One is relativley better controlled in this respect – only in the yellow patch is there a significant negative deviation. In addition, this control of negative peaks isn’t at the expense of spikes in the positive direct; no spike exceeds 12 units. It’s also interesting to note that in the three primary patches, the red component is within three units of the theoretical value in the red patch, and the green in the green patch and the blue in the blue patch are similarly well controlled. Thus, while Aperture is overall closer to the theoretical values, Capture One is perhaps “closer where it counts”.
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