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Adjustable refresh rates for 24FPS on 60Hz native display?

591 Views 5 Replies 4 Participants Last post by  whatsnewsisyphus
Hello, I've seen several topics on this forum pertaining to the methods of converting a 24FPS signal into a 60Hz compatible refresh rate. They all revolve around a 3:2 OR 2:3 pulldown with various methods of interlacing and patterns. Be it 2,3,2,3 or 2,3,3,2 etc.

However an article and test at eratings suggests newer technology may be able to adjust the refresh rate. It doesn't really go into any more specifics but their test seems solid. They test it with a 24FPS signal as well as outputting a 24FPS source via 60i and 60p to determine if the TV will pick up on the uneven display time of each frame and correct it. The test video (which you can download to perform the test yourself) consists of a screen of 24 squares where each square is blackened for 1/24 of a second. This goes on repeating itself. They then set up a camera with a 1 second exposure. If the resulting photo is evenly gray, it displays all frames equally. If a checkerboard pattern results, this indicates that some frames were displayed 2 times and others 3 times.

They mark each of three columns with a yes or no making a nice easy way for consumers like me to see if the new TV they are considering (TCL 6 series I'm considering came up with three yeses) cuts the mustard on 24FPS content without introducing judder from the pull down.

The only thing it says is that to pass, the TV must adjust its refresh rate. So does this mean a 60 Hz tv is capable of changing its native refresh rate to 24, 48 or 72, etc. Hz? If not, how do 60 Hz TVs pass such a test?

I can link to the article, but not sure if I'm allowed.
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This thread is now in LCD Displays.
title edited per OP
Still no thoughts on this?
Yes, supposedly modern 60Hz LCD panels can "lower" their refresh rate to 48Hz in order to address the 24p issue.

However, they still can't "speed up" to 120Hz for better motion options, etc. :)
Yes, supposedly modern 60Hz LCD panels can "lower" their refresh rate to 48Hz in order to address the 24p issue.

However, they still can't "speed up" to 120Hz for better motion options, etc. :)

TCL ones supposedly lower to 48hz but I have not seen it measured anywhere

Vizio we are not sure, might be just pull down
H9F is a 120hz panel so it can just map 1:5
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