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Old 21st March 2020, 10:11   #21  |  Link
wonkey_monkey
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Overall, 24p judder is not a major problem; most people will never even notice it.
True, possibly because Americans have been used to 24p judder since the days of CRTs and 3:2 pulldown.

Edit: there's a neat test on that page where they send an alternating 24p signal to the screen and take a long exposure photograph. If there is judder, it shows up in the photo as a bias towards one of the two frames. Neat!
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Old 21st March 2020, 13:43   #22  |  Link
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why someone will ever need such a test to see something obvious like this is beyond me.

and there are other way to test this beside using additional hardware.
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Old 21st March 2020, 14:01   #23  |  Link
wonkey_monkey
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Because it's not obvious to everyone.
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Old 21st March 2020, 15:27   #24  |  Link
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2018 was a bad year to buy a TV.
Why do you say that? There were some very fine TVs sold in 2018.

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For LCDs refreshing at 24Hz can be technically bad. They cannot hold the liquid crystal in one orientation long term so you get apparent flicker as the pixels drift and then snap back at the next refresh. Of course, you could use 48Hz with frame doubling because most LCDs don't drift much in 21ms but even that could be too slow for a particular panel.
That's not really true. The fluid is effectively used as a capacitor that holds the transistor in the state set by the panel drivers. The combination will hold the for quite a while (in terms of ms). It takes seconds for the image to fade if you stop refreshing the transistors.

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It is also more expensive to support more refresh rates because you need to tune the refresh electronics for each refresh rate, requiring a better controller and more work up front. Not much more expensive today but you do have to spend something to support each refresh rate.
That's why they refresh the panel at 120Hz or 240Hz in good LCD TVs. They're not changing the actual drive rate for the panel much. All expected North American content is a multiple of those that divides in evenly into 120Hz.

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That said, I suspect most TVs don't that support 50Hz today could but don't as a simple region locking mechanism.
What do you mean by support? I can input p25 and p50 into my US model LCD Sony TV. They are supported frame rates. I haven't bothered to confirm if it switches the panel drive to 100Hz. It wouldn't surprise me if it does. The European model of the same TV has to support p24 properly in addition to 50Hz content so it has to switch between 100Hz and 120Hz drive.

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Because it's not obvious to everyone.
It pretty much is if you put two displays side by side. One with a 60Hz refresh rate and one with a refresh rate that's a multiple of 24Hz and show content with motion and pans in them they will quickly realize they don't look the same if told to compare them. They probably won't be able to tell you why, but they will see the difference.
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Old 21st March 2020, 15:43   #25  |  Link
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because in 2018 samsung didn't produce a lot of 120 HZ panels and samsung is pretty much the biggest producer of VA panels leaving you with mostly 120 Hz IPS.


does that mean all TV are bad? no clue why you would come to the conclusion.
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Old 21st March 2020, 15:56   #26  |  Link
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@markfilipak,

Out of interest... What device are you using to play your media files? And what's your Sharp TV's model number?
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Old 23rd March 2020, 05:49   #27  |  Link
Asmodian
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That's not really true. The fluid is effectively used as a capacitor that holds the transistor in the state set by the panel drivers. The combination will hold the for quite a while (in terms of ms). It takes seconds for the image to fade if you stop refreshing the transistors.
Lots of the early VRR monitors had this issue. When the frame rate drops too low they flicker and it was solved by automatically refreshing the display twice when at low frame rates. The image is still there, the pixels only drift slightly, but it is enough to notice it frame to frame below 30-40 Hz, at least with many current LCD panels.

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What do you mean by support? I can input p25 and p50 into my US model LCD Sony TV. They are supported frame rates. I haven't bothered to confirm if it switches the panel drive to 100Hz. It wouldn't surprise me if it does. The European model of the same TV has to support p24 properly in addition to 50Hz content so it has to switch between 100Hz and 120Hz drive.
I think most do, my recent LGs have supported 50Hz properly. Just some don't.
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Old 23rd March 2020, 09:59   #28  |  Link
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I think most do, my recent LGs have supported 50Hz properly. Just some don't.
Yes they do...
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Old 23rd March 2020, 20:51   #29  |  Link
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Yes they do...
You saying all TVs support 50Hz? Are you sure?

Very recent TVs do seem to support 50Hz most of the time but I would still not assume they all do. Maybe it is simply very cheap ones that don't care, and not some region locking nonsense. Using refresh rate support for region locking is hopefully out of date today.
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Old 23rd March 2020, 21:00   #30  |  Link
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You saying all TVs support 50Hz? Are you sure?

Very recent TVs do seem to support 50Hz most of the time but I would still not assume they all do. Maybe it is simply very cheap ones that don't care, and not some region locking nonsense. That idea is hopefully be out of date today.
All TV's in Europe support 50Hz (25 progressive frames and 50 interlaced fields per second)...
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Old 24th March 2020, 00:40   #31  |  Link
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Well, of course! I was only talking about US TVs. Region locking by not supporting 50 Hz wouldn't make any sense with TVs sold in Europe.
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Old 24th March 2020, 09:04   #32  |  Link
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Well, of course! I was only talking about US TVs. Region locking by not supporting 50 Hz wouldn't make any sense with TVs sold in Europe.
As far as I know... All 'smart' Panasonic and LG televisions sold worldwide are capable of supporting 50Hz. Although the feature might be locked out and will require a visit to the service menu.
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Old 24th March 2020, 09:51   #33  |  Link
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I have an el cheapo Panasonic TV with an Innolux MVA panel. My NV Shield is set to 24 FPS and when I switch to it, my TV reports 24 Hz. Not sure whether it is true 24 Hz or it upconverts. Regardless, all looks fine here
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Old 24th March 2020, 10:25   #34  |  Link
huhn
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panasonic well that's easy to test.

just actived pure direct mode and it can't do 24 HZ correctly anymore that's by design don't ask me why.

cheap version are sometimes just that brand in name but produce by someone else but still relative easy test.

there are other ways to test this but i'm not going into that.
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Old 24th March 2020, 10:31   #35  |  Link
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I know that the budget models are produced by the Turkish Vestel but mine is actually made by Panasonic itself in the Czech Republic. I do not use Pure/Pixel Direct as it makes the picture worse. I'm not too concerned with doing native 24 Hz or not. As long as it looks good to me, I'm happy
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Old 24th March 2020, 13:23   #36  |  Link
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You saying all TVs support 50Hz? Are you sure?

Very recent TVs do seem to support 50Hz most of the time but I would still not assume they all do. Maybe it is simply very cheap ones that don't care, and not some region locking nonsense. Using refresh rate support for region locking is hopefully out of date today.
You've yet to define what "support" means in the context of your usage. Is it simply take the format on the input and put an image on the screen, or take the format on the input and display it at a refresh rate that is a multiple of 50Hz?
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Old 24th March 2020, 18:45   #37  |  Link
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I meant accept the format as input and have an entry for it in their EDID. Sorry, I didn't think some TVs lacking support for 50Hz would be controversial. There used to be many TVs sold in the US that would not accept a 50 Hz signal at all, no attempt to display an image when provided with a 50Hz signal. Maybe this is no longer true, and all TVs sold in the US support 50Hz input, but I wouldn't assume that without first making sure if you need 50Hz. Historically 50 Hz support has been surprisingly bad in the US.

On that same note, I also would not be surprised if some TVs that do support 50Hz input end up displaying it with a 60 or 120 Hz refresh rate. I don't have any examples of this though, hopefully it isn't true.
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Old 24th March 2020, 20:50   #38  |  Link
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I may be wrong, but a panel with eg. 120Hz max refresh rate is not fixed to it (or doesn't have to). It can operate at anything lower as well. It's up to manufacture to give such an ability or not. It's even more true for monitors which support adaptive sync. If I'm correct this seems to be coming to TVs as well (not only gaming monitors).
50Hz in USA use to be almost non-existing. No idea how it's now.

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Old 25th March 2020, 01:45   #39  |  Link
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I may be wrong, but a panel with eg. 120Hz max refresh rate is not fixed to it (or doesn't have to). It can operate at anything lower as well. It's up to manufacture to give such an ability or not. It's even more true for monitors which support adaptive sync. If I'm correct this seems to be coming to TVs as well (not only gaming monitors).
50Hz in USA use to be almost non-existing. No idea how it's now.
It's still non-existent for normal people in the US. I only have it from some concert Blu-rays that were shot as 1080p25 and converted to 1080i60 that I restored back to 1080p25.
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Old 25th March 2020, 11:09   #40  |  Link
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It's still non-existent for normal people in the US. I only have it from some concert Blu-rays that were shot as 1080p25 and converted to 1080i60 that I restored back to 1080p25.
If I was a conspiracy theorist, I would postulate that way back in the DVD days, TV's (and players) destined for the North American NTSC market were locked out of PAL 50Hz support, so they could not take advantage of the (technically) 20% improvement in picture quality over their NTSC counterparts!

The organisations controlling the development and distribution of DVD including how their images are transported from player to display, were and still are... pretty anal!
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