Why does my new LED LCD TV look worse than my CCFL LCD monitor?

Question

At work we wanted a large 1920 x 1080 monitor to use with a certain program. Since monitors with this resolution seem to currently stop at 24", we went for a LCD TV so that we could have 26", and in fact we bought the LG 26LE5500 which is a LED LCD TV.

I'm sure the screen would be great for watching movies, but the problem we have is that for computer work, the quality is simply much worse than our existing (CCFL i.e. traditional) 19 inch LCD monitors. The main problem is that text does not appear sharp. If I look at black text on a grey background on my old monitor, I see obviously black and grey. On the new TV, I see black, grey, and slight bits of white at the sides of the black text, as if "shining out from behind". Let me clarify that both monitor and TV are running at their correct resolution, so it is not the old problem of having the resolution too low. This problem exemplifies something about the display which makes it really unpleasant to read text on this screen - fine for a minute but not if you want to work all day with the screen.

Additionally even after playing a lot with the controls, the colour reproduction is not as faithful in my opinion, and the white is perhaps "overly flourescent", however these problems would be acceptable, it's the text problem that is the killer.

The question is: What is source of the problem here? Is it something about TVs that makes them worse as monitors? Is it the fact that it's a LED LCD? Is it something brand-specific, LG's poor construction quality? We want to purchase a different screen to solve the problem, so I need to know where the problem lies. Obviously I will test the screens in the shop, but it's good to understand the technology before entering.

Answer 1

I did some research on this recently, and I finally found an answer that makes sense.

The problem with LCD TVs as computer monitors is that you often run into chroma compression. Most video streams are quite acceptable if you compress part of the color spectrum to reduce bandwidth consumption. While fine for TV's, this is rarely ideal for monitor usage where every pixel literally counts for text rendering.

Wikipedia's entry on chroma compression has a nice side by side comparison on various modes.

Check to see if your TV has a PC input mode. On certain devices, this enables 4:4:4 uncompressed chroma, which should render text correctly.

Try searching for a few test images out there if you'd like to verify it.

Bottom line: Be wary of using an a LCD TV as a monitor unless you know it supports 4:4:4 uncompressed chroma.

Answer 2

Your TV appears to be applying a "sharpen" filter. Many TVs do this because it makes video content look (artificially) more detailed so the TV seems better in the storefront. It works much the same as a sharpen/unsharp mask would in Photoshop--enhances edge contrast in photos but adds halos to text and other crisp images.

Look for a sharpness setting in the TV's menu, bring up a good LCD test pattern (like this one) and turn down the sharpness until the pattern comes out correct or as close as possible. If you can't find any sharpness adjustment, you may be out of luck.

PC mode (as in NBJack's answer) will also usually disable most of the image worsening filters like sharpness and frame interpolation.

Answer 3

Most people agree that LED has superior quality as monitor.

From Using HDTV as PC Monitor :

Turn off any noise reduction built into the TV. Noise reduction does nasty things to text and is meant for use with video content only (if at all). Make sure the video card and television are both set to [...] the recommended resolution from the manufacturer.