Edge Effects on LED Backlit LCD TV's

[bgreinke]

I've just started looking into the different display technologies in preparation for buying a new set in the near future. One thing I've noticed with all or nearly all of the LED backlit LCD TV's I've looked at is that all the images seem to suffer from an unnatural separation of images in the foreground and the background. It's tough to describe, but it almost looks like bad green screening with a halo setting the foreground image apart from the background. I even viewed this on animated material which made me think the issue is not with source or playback device.

Can anyone help me understand what I'm seeing? I'm inclined to think this is a technology issue but I realize it could very well be excessive edge enhancement processing trying to create a super-sharp image. Before I start looking I'd love to know if there are certain features I need to disable prior to evaluating a given set, or in this case an entire technology.

Thanks for any help anyone can give me.

Braden

[rbinck]

Have you seen the same material on a plasma? If so, how did it compare?

[bgreinke]

I've never noticed this behavior on plasma sets I've looked at in the past nor now. While I've not done a lot of quality evaluations, what I've seen on LED backlit LCD's is not a sublte effect so if I noticed it on others, I would think I would see it on a cursory examination as well. The first set I noticed it on I noticed it in passing after watching only about 10-20 seconds of material (if anyone cares, it was the opening scene to Invincible w/ Mark Walberg where he and his buddy are in the stands at the game). Is it possible this is something akin to the color wheel issues with DLP that not everyone picks it up but once you do, your going to always see it?

Braden

[PalmHarbor]

I work for Sony at Best Buy and Samsung has an end cap LED display next to me.
In the 8 weeks I have been standing next to the LED set I have not seen anything
you describe. Never

[rbinck]

I've never noticed it either. Maybe the sharpness was dialed all the way up. That will cause halos.

[darcycoby]

The type of LED backlight system used here is referred to as the Full Array system. This allows for Local Dimming, which enables a wider contrast ratio, even within small areas of the screen ,such as bright stars against the darkness of space.