LCD monitor contrast

[JTsyo]

So what's the difference between 700:1, 1000:1 or 3000:1? Is it something you would notice or only of concern for real high end users?

 

[programmer]

Marketing, mostly. The higher the ratio, the "blacker" black should be. Cheaper panels, are ... cheap, and let a lot of the backlight bleed through so "black" is more like "dark gray" (or purplish or rainbow-ish, depending on the type of LCD panel and anti-glare coating).

In other words, its kind of meaningless. There is no specification that can be used to compare different panels or brands.

 

[CP5670]

So what's the difference between 700:1, 1000:1 or 3000:1?

You can pretty much ignore the contrast ratios published by the companies. Such monitors are often all similar in reality, usually around 400:1 or 500:1. Look at reviews and user opinions on them instead.

 

[Suspicious-Teach8788]

Originally posted by: CP5670

So what's the difference between 700:1, 1000:1 or 3000:1?

You can pretty much ignore the contrast ratios published by the companies. Such monitors are often all similar in reality, usually around 400:1 or 500:1. Look at reviews and user opinions on them instead.

Well each company measures differently and it's kinda like response time. Is it true 8ms response? Ehhh.. probably grey to grey or whatever. They pick the fastest time measured and then quote that or something. Either way, contrast IS good. For the most part you can notice those TN panels and their crappy contrast ratios when compared against PVAs and their 1000:1 or better. I say 1000:1 is pretty good.

 

[CP5670]

For the most part you can notice those TN panels and their crappy contrast ratios when compared against PVAs and their 1000:1 or better.

This is not so true anymore, ever since the dynamic contrast monitors came out. We regularly see TNs with outlandish 3000:1 or more ratings these days.

 

[BassBomb]

Originally posted by: programmer
Marketing, mostly. The higher the ratio, the "blacker" black should be. Cheaper panels, are ... cheap, and let a lot of the backlight bleed through so "black" is more like "dark gray" (or purplish or rainbow-ish, depending on the type of LCD panel and anti-glare coating).

In other words, its kind of meaningless. There is no specification that can be used to compare different panels or brands.

Should, but in reality they are using extremely higher whites to compensate for bad blacks using dynamic contrast to get that kind of contrast

 

[xtknight]

Each part of the ratio of the dynamic contrast measurement isn't taken with the same settings, so it's not really a measurement of anything. 3000:1 is more like the range of the backlight in the monitor rather than any immediate measurement.

Here are some realistic figures.

Old TN: 400:1
New TN: 800:1 to 900:1
Old IPS: 400:1
New IPS: 650:1 to 700:1
P-MVA: 800:1
PVA: 1000:1
S-PVA: 1000:1 or higher

Even though the newer TNs actually do reach 800 or 900 to 1, that doesn't mean they show all the middle tones as well. The viewing angle really restricts the usable contrast. So at best this is a measurement of dynamic range (lowest and highest point) rather than contrast (how well each tone is displayed).

Most panels rated at 3000:1 or even 5000:1 do implement newer TNs which reach a real, static contrast ratio of about 800:1.
Many that are rated 2000:1 or below use older, lower contrast TNs, although this is not always the case. It's pretty rare for a newer high contrast TN not to have a large, overblown dynamic measurement. Sometimes both figures are given (e.g. 226BW: 700:1, 3000:1 DC).

Dynamic contrast is a type of temporal measurement (one taken over time), not a spatial one (taken at once). It measures black at the lowest value of the backlight and compares it to the value of black at the highest backlight setting. The backlight can't be set at two things at once, so it instead changes depending on the scene. If all of a sudden a bunch of dark was shown, the LCD would adjust it such that each dark tone was very distinguishable from one another. As long as you have a scene with both dark and bright elements, the dynamic contrast ratio can't do much for you.

 

[postmortemIA]

usually number over 1000:1 means it is dynamical contrast ratio, useless measure, and real one is well hidden.

EDIT: xtknight have given excellent description of dynamic contrast ratio in his post