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General discussion

contrast ratio and response time

May 23, 2009 7:35AM PDT

Hello, just wanted to know if one brands contrast ratio of 20,000 could be equal to another brands 50,000 contrast ratio. Same question for response times. Also does response times have any thing to do with 120hz

Discussion is locked

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Contarst ratio/response time
May 24, 2009 11:40PM PDT

All manufacturers have very smart marketing departments that do none of us consumers any good. When a display advertises 20,000/100,000 contrast ratio they are typically talking about Dynamic Contrast not Contrast ratio(static).This gives the benefit of realizing the potential static contrast ratio of the LCD panel in dark scenes when the image is watched in a dark room. Most people on this board would probably say the same thing as me,in order to get proper calibration leave it off. It will make the black or dark scenes look darker, but often will blow out the brighter areas of a scene/game. Some tv's will also have ambient light sensor for judging dynamic contrast, so you might notice the backlight adjusting itself from scene to scene. Most static contrast on lcd's start at around 700:1and as high as 5000:1( take this with a grain of salt, with a dynamic of 1,000,000:1 or whatever ever may win them the spitting contest that month. Now for response time/refresh rate. I know that everyone is pushing for the 120hz/240hz tru-motion or whatever the hot marketing term of the minute is? . Film is meant to be grainy or juddery. The 120hz has very little effect on motion blur, but the after effects of being sent through the video processor creating the smoothing motion does. I don't care for the overly compressed and digital look of film after going through the processor. For me being a huge fan of films some of my favorite film are very dark and grainy, so this would take away all that. Example David Finchers "Seven", if you are a fan try imagining watching this film if it were being filmed by a video crew for entertainment tonight, losing all post production lense filtering and effects. Leaving what was once a moody dark film rendered hospital sterile and unnatural. Go to a big retailer like best buy , that will have a demo unit set up have them show you Pirates of the Caribbean, with(think Ray Harryhausen)and without it on you'll see what I mean. Response time I have seen that anything 10 and below should hand any fast motion content. I have had a few lcd's recently with response times as low as 4ms, not handle motion blurring or ghosting as well as my current 8ms tv. If that is a concern go for plasma tv's which generally have a 600hz or higher refresh rate, completely alleviating the need for response times.

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Watch, don't read
May 25, 2009 4:48AM PDT

In stead of spending 4 hours reading through all the marketing stuff, spend one hour to actually look at some TV sets and buy what you like best. That's how I bought mine and I haven't regretted it.

That's for the image quality, if you need other specific features or inputs/outputs, that can be compared on paper of course.