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Plasma and LCD contrast ratio


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Old 05-01-2008, 11:30
ebony_rascal
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How important is contrast ratio when choosing a TV ... I am looking for a 42 inch.

I notice that Pioneer Plasmas are now in the region of 16000:1 and do look fantastic however the Panasonics are only 5000:1 but still look great compared to some other makes which have a contrast ration of 10000:1 I am confused.
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Old 05-01-2008, 11:32
sancheeez
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From what I know of it (I'm far from an expert I should add), they all have different ways of measuring this.

So .... you can't really use it as an accurate guage due to different manufacturers using different interpretations and scales when representing this figure in their specs.

Helpful eh!
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Old 05-01-2008, 12:13
meltcity
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The contrast ratio measurement used by current TV manufacturers is best thought of as a guide to black levels.

Anything above 5000:1 is good, but nothing can match the black levels on Pioneer's eighth generation Kuro plasmas. LCDs tend to have a lower contrast ratio because the liquid crystals are unable to block all of the light from the CCFL backlight (prototype LCDs with LED backlighting do not have this problem). They are slightly brighter than plasmas, though.

For more on this see this article:

http://www.practical-home-theater-gu...ast-ratio.html
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Old 05-01-2008, 12:13
Nigel Goodwin
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He's quite right, there's no standard method of measuring contrast ratios, so most figures that look suspiciously high are probably using a method that makes them look good, rather than actually being that much greater (and may even be worse in reality).

As always, go and see them and see which you prefer - never buy just on specs, not even on honest specs, and certainly not on contrast ratios.
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Old 05-01-2008, 12:30
CWatters
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One of the new LCD panels uses an array of LEDs for the backlight. These can be individually controlled eg dimmed to improve black areas. However they can't use millions of LEDs so the resolution of the backlight is quite low. eg the contrast is only improved in large areas of black not smaller area. That should improve the numbers much more than the image - although the image may also be good.
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Old 05-01-2008, 13:04
late8
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I have seen the 10000:1 claim on Panasonic plasmas??? - what ever way they are fantastic screens and have high ratings- all the reviews recommend the Panasonics.. if your budget cant stretch to a Pioneer the Pannys are the next best thing and blow LCD away in overall picture performance.

Just a tip- if your looking for sharpness the 37" Panasonic Plasma is much better- 5" less i know but your getting a sharper pic.
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Old 05-01-2008, 13:23
bobcar
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Just a tip- if your looking for sharpness the 37" Panasonic Plasma is much better- 5" less i know but your getting a sharper pic.
Only if you sit at the same distance - if you move closer they will not be sharper. As always it's down to size versus distance.
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Old 05-01-2008, 15:23
meltcity
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I have seen the 10000:1 claim on Panasonic plasmas?
That's right; the latest Panny plasmas are rated at 10000:1. I noticed that Sony's X range of LCDs is rated at 7000:1 contrast, while the older W range is rated 1800:1. You can take it for granted that Sony's Z LCD range will have a contrast ratio of at least 10000:1 (or perhaps more). It seems that when one manufacturer doubles or triples the claimed contrast ratio the others are obliged to follow suit, even though no one will ever see these ratios in real world situations (except when looking at a plain black screen or a plain white one - how often do people do that?).

It would be better if TVs were rated by ANSI contrast ratio (as explained in the article above). Unfortunately most TVs have a rubbish contrast ratio, so manufacturers don't want to use it!
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Old 05-01-2008, 16:32
CWatters
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It's interesting to note that some Full HD (1080) displays have a lower contrast ratio than the equivalent HD Ready (768) display...

Example:

Panasonc TH-42PZ700WALL (1920 x 1080) = 5,000:1
http://www.panasonic.co.uk/plasma-tv...wall/index.htm


Panasonic TH-42PX700WALL (1024 x 768) = 10,000:
http://www.panasonic.co.uk/plasma-tv...wall/index.htm
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Old 05-01-2008, 18:56
skinj
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The other thing to bear in mind with an lcd is that they are capable of much brighter images (overly bright in normal living room situations) when compared to plasma. This allows the LCD contrast ratio to be larger but skewed to starting with less black blacks and finishing with whiter whites!
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