Originally Posted by ADU
Disabling 2170P-3/SYSM*, SHF0, F1LV and LTLV seems to eliminate most of the ringing/overshoot on my TV. There appears to be a simple Sharpness offset control: SHOF (different than SHF0) there as well.
I did extensive experimentation over the summer and fall with my similar Sony 36XS955, and I have detailed the results as well as I can in a chart I have prepared as a PDF document, attached here
to post #707.
Much of what ADU has said is true, but I caution that some of the different filters/enhancers applied to the video signal cannot be "eliminated" but only optimized. In particular, 2170P-3/SYSM is significant changed by the three settings of 0/1, 2, and 3; but 3 isn't "off." I.e. if you choose SYSM = 3, minimum effect seems to be with the Sharpness slider at "Min," but if you choose 2 (as I generally do because of its refined effect), "neutral" is with the Sharpness slider at about 12-15. Lower than that *softens* the image.
Further, a couple of these filters that can enhance edge sharpness appear to me not to be simple high-frequency boost (like an audio trebel control) but to be working in the *time* domain, deriving edge information from the video, taking a derivative of it, and adding it back to the video, leading, lagging, or centered on the edge in question. This woud produce, if well done, a desirable unsharp-mask effect, as one can do to digital stills in Photoshop or the like.
My goal has been to (1) understand the variious filters and enhancements; (2) determine how to control them; (3) figure out how to set up a really neutral-looking display, with stunning detail but without ringing or overshoot; and (4) what controls to use for improving second-rate video.
Much of (1) and (2) are answered in the chart mentioned above.
(3) Was fairly easy to achieve, given the complete image-neutrality of certain DVDs, neither soft nor sharpened. Monsters, Inc and the AVIA resolution targets are great examples.
For (4), we're stuck with the Sharpness control, unless you reconfigure a couple of the Picture modes for your own purposes -- which is what I have done.
The abovementioned chart is *very* specific to the Sony DA-4 chassis, common to many of these related XS, HS, and XBR CRT sets. Note that there are two unobvious locations in the DA-4's processing where sharpening is applied -- and well-hidden: in 3D-COMB and 2103-1. The sharpening in 2103-1 is especially obnoxious, in my opinion, and I eliminate it, period!