Could someone would a 120hz monitor do a test for me?

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Majinhoju

[H]ard|Gawd
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I'm curious.

I've noticed on 60hz lcd's, anything that scrolls across the screen blurs a bit until it stops moving. that includes images, text or even looking left and right on a fps shooter.

I'm thinking it has something to do with the refresh rate not quite being fast enough to keep the image clear when it moves on screen. i could be wrong though..

Could someone do a simple test for me? if you have a 120hz lcd monitor, take a window or picture and just move it across the screen. does it blur at all when in motion?

I've done this test on a 80hz and 100hz crt monitor and even in motion, the text is very clear and easy to read, but on my 60hz lcd, it blurs until it stops, even when scrolling slowly.
 
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Make sure you are comparing apples to apples though.

If there are differences in TRUE response time, you won't know if the difference you are seeing is the RR or the RT.
 
Majinhoju said:
Could someone do a simple test for me? if you have a 120hz lcd monitor, take a window or picture and just move it across the screen. does it blur at all when in motion?
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It does, a little bit (BenQ XL2410T). Blurring is caused by response time and there are no LCDs with 0ms response time, so they all blur to some degree.
 
Give the Readability test (F4) in PixPerAn a go and see how high you can go. It's not an exact science as it can depend on how lucky your guesses are and also people see blurring differently, but at least it's something that you can use to directly compare.

Obviously someone with a 120Hz monitor needs to also take the test and then you can kind of see if it's any better.
 
tQz1 said:
It does, a little bit (BenQ XL2410T). Blurring is caused by response time and there are no LCDs with 0ms response time, so they all blur to some degree.
Click to expand...
From what I understand, as long as your response time is lower than the refresh rate, you shouldn't see any blurring, so 0ms is not necessary.

The problem though is determining true response time.

Advertisers use misleading lab figures like gray to gray IIRC and so list 2ms or some such nonsense, and real response times are much much higher and probably above 20ms.
 
Even if there was an LCD with 1ms response time across all transitions there would still be motion blur due to the sample and hold effect. 120Hz reduces the blur but doesn't get rid of it.
 
Walker said:
Even if there was an LCD with 1ms response time across all transitions there would still be motion blur due to the sample and hold effect. 120Hz reduces the blur but doesn't get rid of it.
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I know that too high a refresh rate can be a bottleneck for a 60hz display resulting in effective dropped frames, and of course then especially so for 120hz, but how does sample and hold relate? I'm not too familiar with that.
 
Dragging a window of black on white text, here are my observations:

Samsung 2233rz:
Text becomes bolder. Aggresive RTS? A slow circular motion results in readable text, albeit flickering.

Dell 2209wa:
Text remains as it should. There is no change in its boldness. Due to 60hz text is unreadable at all speeds.

Sony FW900:
Text remains unchanged and is readable at almost all speeds. One small caveat - due to phosphor decay any white on dark objects/text is less readable and very distracting/possibly headache inducing.

TBH, I think the Dell 2209wa would make a better/faster 120hz screen than all existing TNs.
 
bearbear said:
Give the Readability test (F4) in PixPerAn a go and see how high you can go. It's not an exact science as it can depend on how lucky your guesses are and also people see blurring differently, but at least it's something that you can use to directly compare.

Obviously someone with a 120Hz monitor needs to also take the test and then you can kind of see if it's any better.
Click to expand...

With my XL2410T I could get the text right at speed 7, speed 8 took some attempts before I got it right. Same with 9. Any higher and it starts getting impossible.
 
sadbuttrue said:
Dell 2209wa:
Text remains as it should. There is no change in its boldness. Due to 60hz text is unreadable at all speeds.

TBH, I think the Dell 2209wa would make a better/faster 120hz screen than all existing TNs.
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I believe you can get the 2209wa to run at 75Hz, I wonder if it'll be less blurry.

tQz1 said:
With my XL2410T I could get the text right at speed 7, speed 8 took some attempts before I got it right. Same with 9. Any higher and it starts getting impossible.
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On my Dell U2311H (e-IPS), I can consistently get 7, at 8 I got right 4 out of 5 tries, at 9 I got right 2 out of 5 tries. Any higher and it's unreadable, although even at 9 it was already pushing it. I believe I got somewhere around 14-15 when I tried the PixPerAn readability test on my old CRT a few months back, before I got bored and stopped.

Here's a chart made by ExtraHardware that lists the readability of other monitors (using the same PixPerAn test), seems like the highest for any monitor they've tested is 7:

 
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Thanks everyone, I think i have a clearer idea of how it all works. 120hz seems to definitely help, but i guess crt is still the king with keeping moving images/text clear.

i'll probably invest in a 120hz lcd once they start dropping in price.
 
pixperan readability test:

7 - Samsung 2233rz
8 - Dell 2209wa
6 - AX200 Projector

The Sony is in storage so I can't test, but last time I tried it was in the double digits.
 
sadbuttrue said:
pixperan readability test:

7 - Samsung 2233rz
8 - Dell 2209wa
6 - AX200 Projector

The Sony is in storage so I can't test, but last time I tried it was in the double digits.
Click to expand...

In 120hz pixperan render the image at 120fps, so it doubles the speed too. You have to multiply by 2 the results on your 2233rz at 120hz to compare to a 60hz display.
Your result of 7 in reality is 14 which is great for a lcd.
I have this monitor and did the same test.

C'mon, just moving a window its noticiably smoother :p
 
I did 15 on that Pixperan test with my Sony G520 Trinitron CRT monitor, running at 85 hertz - 85fps, but after that it's more of a case wether your eyes can track fast enough to read it :)
 
Bergkamp said:
In 120hz pixperan render the image at 120fps, so it doubles the speed too. You have to multiply by 2 the results on your 2233rz at 120hz to compare to a 60hz display.
Your result of 7 in reality is 14 which is great for a lcd.
I have this monitor and did the same test.

C'mon, just moving a window its noticiably smoother :p
Click to expand...

I tried it at both 60hz and 120hz, with vsync forced on and off, just to be sure. In all 4 cases the result was the same. It really is only 7. This makes sense when you remember that the response time of a 120hz lcd is no better than that of a 60hz lcd. It may be displaying more frames per second, but because the response time is so poor they bleed into each other. This is probably what causes the "boldness" when you drag a window around.
 
So... rigor mortis aside, could someone do the same test with the newer 120hz panels (asus vg236h, samsung s27a950, etc)?
 
lol, I just realized my thread title doesn't make any sense.

I meant "with", not "would"

damn typos :D
 
Ducman69 said:
I know that too high a refresh rate can be a bottleneck for a 60hz display resulting in effective dropped frames, and of course then especially so for 120hz, but how does sample and hold relate? I'm not too familiar with that.
Click to expand...

The way LCD displays show images is not very compatible with how our brain interprets them. Since frames are changed one after another our eyes tend to average the motion thus creating motion blur. CRT's don't suffer from this because they flicker at a certain refresh rate causing a very very short period where the CRT isn't projecting anything. This allows our eyes to track the image properly.

They've tried introducing this on some LCD TVs by strobing the backlight and it seems to vary how well it works based on implementation. The bad part is that it introduces more input lag so not good for gaming. Correct me if I'm wrong, but even on OLED displays that have pretty much no response time you would still suffer from the sample and hold effect.

Perhaps in the future the processing is fast enough that no input lag is introduced and the display tech suffers from no response time or refresh issues.
 
The fastest I've ever seen on this text test was my BenQ FP241VW with the BFI (black frame insertion) technology activated. I was able to read up to 11 easily, 12 with some errors and 13 about 30% of the time.

Unfortunately this technology could induce flickering which could create headaches.

Keep in mind the A-MVA panel in the FP241VW was not known as the fastest panel so response time itself is not necessarily as much of a factor as indicated.

So I'd have to defer to Walker and kasakka as being correct that the "sample and hold" effect is probably the issue.

Even the Super AMOLED display on my Samsung Galaxy S shows motion blur and OLED is supposed to be pretty darn fast.

Alternatively my Acer GD235HZ @ 120hz I was only able to get up to 8 and not very accurately.
 
Is anyone else as amazed as I am that the 120Hz displays are not doing better than 60Hz displays on this test? I was thinking about getting the S27A950, but now I am not so sure. Can anyone with an S27A950 please run this test?
 
Again:

Bergkamp said:
In 120hz pixperan render the image at 120fps, but it doubles the speed too. You have to multiply by 2 the results on your 2233rz at 120hz to compare to a 60hz display.
Your result of 7(at 120hz) in reality is 14 at 60hz which is great for a lcd.
Click to expand...

I dont know about other 120hz models, i guess is the same.
 
nhtalbot said:
Is anyone else as amazed as I am that the 120Hz displays are not doing better than 60Hz displays on this test? I was thinking about getting the S27A950, but now I am not so sure. Can anyone with an S27A950 please run this test?
Click to expand...

It's just a standard ghosting test. As Digital Versus has shown basically all 120Hz Monitors are amongst the fastest that you can buy.
 
Bergkamp said:
In 120hz pixperan render the image at 120fps, so it doubles the speed too. You have to multiply by 2 the results on your 2233rz at 120hz to compare to a 60hz display.
Your result of 7 in reality is 14 which is great for a lcd.
I have this monitor and did the same test.

C'mon, just moving a window its noticiably smoother :p
Click to expand...

The speed the text moves at is the same for a given tempo, no matter what the refresh rate is on a CRT, and I don't see why that would be different for an LCD.
 
I dont know about crt, this app is for lcd. It Render the frames fixed to refresh rate in my tests.
I noticed inmediately when launching the program, the cars were too fast!.
 
I have a Planar SA2311W and passed 12 on the pixperan readability test at 120hz with overdrive on (after a few attempts). The text gets distorted at that speed, but it is possible to tell the difference between most letters.

That said, I was a bit disappointed coming from a 2209WA at 75Hz.The Planar feels a bit smoother, but is nothing like a good CRT. Also, overdrive can create distracting artifacts in certain conditions.

The biggest improvement is that there is almost no tearing at 120hz.
 
120hz are for games with more quick motion. Enhanced motion perception is the main reason to get it. It's beneficial in 99% of games but most effective for FPS.

You'll never get rid of the blur in LCDs even with 600hz. Unless 300hz of that is used for black frame insertion. Wouldn't even require that much. Ideally an LCD with 120hz and another 120hz scanning backlight would be king right now. They would likely call this 240hz, like they do with TV tech, except in an 240hz TV its got a 60hz panel, with 60hz of frame interpolation, and 120hz of black frame insertion. Which makes it a very fake 240hz.
 
i got a result of 7 with my samgsung sa950 120 hz. 8 if am lucky. but its like the guy said, if the image is moving twice as fast then those with 60hz, it is sort of like getting a 14
 
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