HDTV: Contrast Ratio.

Before comparing different HDTVs available in the market, it is necessary to know the parameters on which basis we can compare them. One of those parameters is ‘Contrast Ratio’.

• Contrast ratio denotes the difference between the brightest whites and the darkest black a display can show.
• The higher the contrast ratio, the greater the ability to show subtle color details. A 500:1 ratio means white is 500 times brighter than black.
• Normally A contrast ratio of 400:1 or higher is good.
• Be careful though. Manufacturers often overstate this number and it's a good idea to compare screens side-by-side with high contrast scenes.

Panasonic TH-42PX60U 42	10000:1
Sony KDL-46XBR2, 46 Inch Bravia XBR	7000:1
Panasonic TH-50PX60U 50	10000:1
Sony KDL-40XBR2 40" Bravia XBR	1300:1
PANASONIC TH-42PX600U 42" Plasma HDTV Television	3000: 1
Panasonic TH-50PX600U 50 in Plasma TV	10000:1
Sharp AQUOS® LC-52D62U	10000:1
Sony KDLV40XBR1 40" High Definition XBR LCD TV	7000:1
Sharp Aquos LC-42D62U 42" 1080P High Definition LCD Television	1200:1
Samsung LNS3251D 32" LCD Television	4000:1

Here are some link if you are looking for more info on this subject :

http://www.jakeludington.com/ask_jake/20051016_hdtv_contrast_ratio.html
http://www.cnet.com/4520-7874_1-5107912-4.html