Does contrast ratio make a huge difference on lcd tv"s?

Question

the numbers vary widly i just want to know for example if 15000 is that much better than 10000 for instance.

Answer 1

Since there are no standards for reporting contrast ratio at present the numbers you see are pretty much meaningless. Some sets report "dynamic" contrast ratios but this means even less. In reality there are very few TVs that can do much more than 2,000:1. If it is reported always go with static contrast ratio and not dynamic cr.

Some LCD sets use a method of cheating by lowering the backlight in dark scenes to give more apparent cr but this does not really improve the cr, it only looks like it. And if there is a bright spot or two in the scene using this method can throw everything off.

BTW a projected movie has a cr of about 500:1.

Answer 2

While it is true the numbers themselves have little to do with contrast you will actually see, that doesn't mean they are meaningless.  Contrast ratios are measured under conditions unlike normal viewing in order to get the best numbers (full-screen black vs full-screen white).  However, all the manufacturers do this, so the numbers are valid for comparison between sets.  Contrast ratio is an important spec for LCDs, as this is one area where this technology is behind others (plasma, DLP).

Numbers such as 15000:1 or 10000:1 are "dynamic" contrast ratios, obtained by lowering the level of backlight in dark scenes.  While some people criticize this, it makes a different when a scene goes dark or fades out, because a poor black level is most visible under those conditions.

Static ratios are not always reported, but are usually less than 5000:1.  These should indicate the difference between whitest and darkest part of the same image, but are usually measure full-screen back vs full-screen white but with the backlight control turned off.  

Finally, the importance of contrast ratios also depends on viewing conditions.  If you watch in a lighted room, you don't need as high a numbers as when you watch in a dark room (the room light will mask the black levels).

Overall, the higher the ratio the better; but once dynamic contrast reaches 10000:1  and static reaches 5000:1,  any higher numbers will make very little difference, and would only be noticed in darkened environments.