LCD contrast-ratios

Question

In modern LCD monitors, is there any noticeable difference between a 15000:1 (e.g. this monitor) and a 50000:1 (e.g. this monitor) contrast ratio? Or is it just marketing hype?

Same thing with a 2ms vs 5ms response time.

Answer 1

1:50000 is definitely marketing hype. They measure the white at the brightest backlight point and the black at the darkest backlight setting, or even turned off! S-IPS monitors are aroun 1:700-1:800 in real life today TN and H-IPS monitors are around 1:1000 S-PVA monitors get up till 1:1400 S-IPS big screen TV's get to 1:2000 S-PVA big screen TV's get to 1:3000 Plasma's can get to 1:5000 That's about contrast in reality. All higher numbers are worth nothing.\

About the respons time: There is two things to consider in this:

• Pixel response. In a TFT screen it is harder to change a pixel from say 60% grey to 65% grey than from black to white. TN panels are very good in this, where S-PVA needs a major overdrive power surge to activate fast transitions. This number is mentioned, and is good on most screens today. Some displays can still show some trailing in movies or games due to no perfect response or overdrive. 5ms response with no trailing looks better than 2ms with trailing. This number says not that much as it got much attention the last years.
• Processing time (input lag). This time is almost never mentioned, but critical for serious gaming! There are 3 big reasons for input lag. On TN displays only 200k colours can be shown. To get the idea of true 24 bit colour, the screen logic calculates either a dither pattern, or a kind of pulse-width dimming of the pixels. S-PVA and S-IPS have a similar circuit to calculate overdrive characteristics to get the pixels to the next shade based on 2 frames of input. Last is upscaling and analog conversion processing. These three processing tasks put a delay between the actual input of the screen image, and the display. With most TN screens and some S-IPS screens the input lag is under 1 frame. With other IPS panels and big TN screens (>23 inch) input lag is around 2 frames. With S-PVA input lag is mostly around 3 frames.

Answer 2

If I was you, go to your local big computer shop and try to find either the same model or ones with similar specification to compare.

A lot of it is marketing spiel. I see monitors all the time that say fastest 2ms refresh - never see blur again e.t.c. - I am using a 7 year old NEC monitor (1880SX) that has a refresh rate of 33ms and a contrast of (I think) 250:1, at its time, it was also rated as "never see motion blur again!" - I think it is brilliant and would not change it for the world.

I have a second monitor that is newer, MUCH higher specifications, however you would think it is older when you look at picture quality (however, it is still not bad!)

Also, shockingly, Manufacturers lie! even if one has a higher rating than another, it may have been under a special condition that you would never be able to repeat. The only real way to compare is to buy it, or look at the model and see!

Answer 3

Contrast ratio is something desirable to look for when purchasing a monitor. You see colors at their "fullest" so to speak. Whites at their brightest, black at its deepest and darkest (even though you will probably never set them very high). Wikipedia explains it better than I can:

The contrast ratio is a measure of a display system, defined as the ratio of the luminance of the brightest color (white) to that of the darkest color (black) that the system is capable of producing.

As with response time, it is what it sounds like - How long the monitor takes to respond and change its pixels from black to white or vice versa. Typically you won't notice, but to gamers it's pretty important and makes things look smoother :)