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LCD contrast-ratios

LCD contrast-ratios

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?

Asked by: Guest | Views: 33
Total answers/comments: 2
Guest [Entry]

"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."
Guest [Entry]

"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 :)"