What is edge enhancement?  

There is electronic "ringing" that originates from such things as poorly impedance-matched components and sharpness control overuse, but the so-called "edge enhancement" is usually applied during the digital video "authoring" transferring process (for what is worth, I do not believe EE exists in HD anomorphic masters). Once the EE is applied to the video signal by the authoring technician or telecine operator, there is little or next to nothing that we can do to mitigate or eliminate such pesky, odious artifact.

I agree with Jeroen: edge enhancement destroys the illusion of viewing video-originated images in cinema-like settings. EE should never be used neither as a crutch nor as an alternative to poor QC or whatever the reasons for its use. The DVD format doesn't need it!!... http://www.avsforum.com/ubb/mad.gif

-THTS

You may be seeing Y/C delay issues. If you don't see it in still/pause on a black and white image but you see it with movement in color images your luminance and chroma may be out of sync. This may be a DVD player adjustment a projector adjustment or a problem with the DVD itself. See if it is visible with multiple DVDs. The description you are giving is not edge enhancement.

Hank,

If you're seeing blue fringing then it is a misconvergance error; the blue tube needs to be properly aligned to the red and green CRTs so that all three produce pure white lines in a crosshatch pattern...or close as possible.

The blurring or out of focus effect has nothing to do with the gray scale; that's altogether a different issue.

Of course, neither of those two issues have anything to do with either electronic ringing (I would also include chroma/luminance or any other video processing circuitry delay here as well) or edge enhancement (the sole province of software sourcing) matters.

Hope this helps...

-THTS