Take a look at the Canon 10D shot below. The original shows the gray pelican at an acceptable level of sharpness while showing the orangish flamingo at the same distance a horrible blurry mess. This effect of Bayer sensors not having consistent sharpness for gray shades versus colors often leads to some parts of the image looking sharper than other parts. This effect, I believe, fools your perception of depth in the photo because focus is not consistent in the same planes.

Basically, your eyes see a blurry subject and a sharp one in the same focal plane (distance from lens) and don't know how to "decode" the image, making it look like it has less depth. I've been fooling with a new filter that reverses the "sharpness inconsistency" of bayer images by equalizing sharpness over the color range. Here's an example of what the filter can do. Note how the equalized image on the right appears to have more depth (I call it "presence") due to the fact that the orange birds and green grass now have the same level of sharpness as the gray details like the pelican and the water. This filter will soon be available in Qimage. Note that the filter cannot bring back details that are lost due to the AA filter, poor red/blue resolution, and other problems with Bayer sensors, but it sure does help improve the "3D effect".

http://www.ddisoftware.com/testpics/sharpen-eq.jpg;

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Mike
http://www.ddisoftware.com