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#### jpapin

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What is contrast ratio (in layman terms). Is a ratio of 3000:1 better then a ratio of 800:1? How is it better?

If a Plasma TV has a brightness of 700/m2, what does that mean. Is that better then a brightness of 600/m2?

#### will792

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It is relatively simple. A contrast ratio is a ratio of a white point brightness on a monitor to a black point . If you have a test signal that splits the screen in two halfs, one is black (Red level =0, Green level = 0, Blue level = 0) and one is white (Red level = 2^8, Blue level = 2^8, Green level = 2^8 for 8-bit signal) brightness measurements of each half would give numbers for contrast ratio calculation, i.e. black level = 0.3 cd/m2 and white level = 400 cd/m2. The contrast ratio is 400 / 0.3 = 1333.

Brightness level is straightforward, the higher it is the brighter picture is.

Will

#### jpapin

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Thanks for your reply. I am still in the dark on the obvious question. Will a ratio of 3000:1 give you a better picture than 800:1. A salesman was showing me a tv with 3000:1, but said that it may not be any better then a tv with 800:1. Please clarify.

#### Ken Ross

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With all other things being equal, the higher the contrast ratio, the better the picture. You'll get brighter whites and blacker blacks. Poor contrast ratios lead to blacks that are rendered gray and an overall brightness that might look subdued if you watch with the lights on.

#### 3.1415926 pi

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will792, that has to be the best laymans explanation I've ever seen!

VB

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Will turning down Brightness and/or contrast settings prolong life expectancy of Plasmas? I currently have my Pio 1110 below factory settings for Brightness and above the mid point for contrast. Thanks.

#### turt

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Quote:
 Originally posted by kyad02 Will turning down Brightness and/or contrast settings prolong life expectancy of Plasmas? I currently have my Pio 1110 below factory settings for Brightness and above the mid point for contrast. Thanks.
YES.

#### 3.1415926 pi

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turt, do ya think succinct might be a better moniker??

Cheers, VB

#### will792

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Quote:
 Originally posted by jpapin Thanks for your reply. I am still in the dark on the obvious question. Will a ratio of 3000:1 give you a better picture than 800:1. A salesman was showing me a tv with 3000:1, but said that it may not be any better then a tv with 800:1. Please clarify.
The contrast ratio alone would not describe quality of the picture. Example if a plasma panel can produce 3000 cd/m2 highest brightness and has 3000:1 contrast ratio the level of black is going to be 1 cd/m2 (grey).

There were several postings in this forum describing measured black levels and contrast ratios and none were close to claimed numbers. There was some correlation between claimed and measured characteristics. I think Panasonics had 1200:1 for new panels while Samsung had 400 or 500:1.

Will

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