LCD Contrast ratio???

[DT1009]

I am currently shopping for a 40 or 42" LCD and have narrowed it down to three brands, Sharp Aquos, Sony Bravia and Samsung. What confuses me is that the Contrast ratios range from 1200:1 (Aquos) to 15,000:1 The Sharp has a great picture in the store but that seems like a much lower contrast ratio than the other 2 brands (and most other brands).
What should this spec really be and what does it control?

 

[MDS]

Contrast is the difference between the whitest white and the blackest black. The 15,000:1 contrast ratio for the Sharp is considered 'dynamic contrast ratio'; in other words what you get when the TV is doing special processing.

I've been looking at the Sharps too and from what I can gather, you only get the higher dynamic contrast ratio when the Optical Picture Control feature is turned on. Likewise, the 4 ms response time is only when the Fine Motion feature is on.

 

[DT1009]

From some of the posts I've read on adjusting an LCD TV once you get it home, they seem to recommend turning all of those special effects processing off and sticking with 5 major adustments.

 

[BMXTRIX]

Contrast ratio can be measured a number of different ways, but at the end of the day is almost always a manufacturer inflated lie that results from testing 100 or 1,000 different displays to find the ONE that gives them the best numbers.

Reality dictates that ANSI contrast ratio, which is generated by putting up a checkerboard pattern of white/black squares, is often in the 500:1 range, even for displays with full on/full off contrast ratios that are 10,000:1 or more.

So, read your reviews, do your homework, and go look at some sets that interest you with your own demo material.