Here is what the poster said about the Sony 790 settings, I might order one and compare it to some other sharpening algorithms just to see how it matches up with and without the Darbee.
"Thats because they dont call it reality creation on the s790. Its hidden in the custom picture setting 1 and 2. Its like reality creation, in 2 parts, First called texture remapping, and the second slider is called super resolution. I compared it to the RC on my sony HW50es projector and it does more or less the same thing. Makes cheap projectors such as the HD33 and W1070 a LOT better especially in 3D mode."
I like the Darbee, but it's sort of borderline on calling it a sharpening filter, it is a modded contrast enhancement / luminance adjustment using an edge-ratio contrast formula. The main difference, it enhances the difference in gain of the image inside the edges between objects more than the edges themselves, whereas a standard sharpening filter mainly enhances the edges because edges tend to be the highest contrast so when you see an edge of something it is generally a transition in color completely (think like the blades of a grass to the blue sky). The advantage to the Darby's method is that because it is NOT as quick to enhance edges and noise as other filters, that it does not actually affect the entire picture as much. Though this is also a disadvantage to some degree, hence why just the Darbee alone can benefit from an additional MILD sharpening filter to complement it. The Darbee does not stand alone for sharpening IMO, but for what it does almost no other sharpening filter uses the same formula it uses, that is what makes it so unique. That said, for any source with any noise in it, I would turn off most sharpening filters. Sharpening filters are made to be adjusted depending on how much noise or lack of anti-aliasing the source you are watching has.
This difference can be easily demonstrated by the effect the Darbee has on HTPC text, which is very little. I don't know the math formula being used obviously, but presumably it would be something with a lower and upper bound limitation that restricts the Darbee from modifying the areas of the image that already have the highest contrast (though I'm sure the math is quite complex to do this), that is how it presumably avoids edges.
If you crank up the Darbee enough, it starts affecting the edges much more and since it's not made for that it messes things up, but that is probably because the upper and lower bound restrictions to where the formula is applied are more lax as you increase its settings (but still not lax enough to affect black text on white). Well, it's something like that, even if I don't have it exact, the theory is close enough.
Edited by coderguy - 4/3/13 at 11:43pm