What makes a fast LCD Monitor faster?

[BucklingSpring]

Hello guys,

(If you don't feel like reading, go straight to the bottom line)

I have been looking at the DELL U3011 for a while. Then just before clicking purchase, I ask my wife for an educated opinion. She said "Jeez! Why is it so expensive?". I told her it was producing outstanding and reliable colors. Then she said with her ridiculously obvious logic – "Must be nice for someone not color blind". Doh, I always forget about that defect. It's very light, I pass some color tests and some I don't. I'm ok with colors but I can't see as much nuances as a normal person do. So, I went to plan B and showed her the Viewsonic VX2739WM. The "first 1ms" on the market according to Viewsonic. She said cool, we can finally get rid of your fat radioactive monster.

So I finally got rid of my massive 90 pounds 22" CRT. After almost 10 years of great service, it was time to decommission this nice fellow. It took me a while to make the move. The LCD technology improved a lot in the past years and the cost for a decent monitor is now quite reasonable. Except for the U3011 of course. I'm now typing this message in front of a new ViewSonic VX2739WM.

My cat was the first to notice the change. I don't like him sitting on my keyboard when I'm busy typing. He knows the drill very well. When he wants attention and I'm typing, it takes only two steps from the floor to the top of the monitor. The 22" CRT had a warm estate the size of a golf court perfectly fit for a cat who wants to take part of the action.

This is him:


Here he comes, 5minutes after I replaced the fat bastard for the slim Jim. The poor fellow was about a foot over the top when he realized there was none to land on. Cats and Mike Jordan are the only two things on earth that can defy gravity for a moment. Then he disgracefully crashed behind the LCD and the wall. It was hilarious. I whish I had a camera to film this in slow mo. Could have won a funniest video award. Then 6 hours later, he did it again. More cautious, he bounced twice on the top edge of the LCD before giving up. The monitor stand is not made to hold up against a 10 pounds cat bouncing on it… I really taught it was going to break. Although the laughs worth the price of the monitor, I'm glad it didn't break.

It's a decent screen at best. As warned in multiple reviews, there is about a cm of light bleeding at the bottom which is easily noticeable on blacks. I'm no monitor expert, I don't have the right terminology for it but the color of a given pixel is influenced by the color of the pixel besides it. A bunch of yellow pixels will give a yellowish tint to the white pixels next to them. Is this what they mean by cross color artefacts? Anyway, even a color blind guy like me can notice on still images.

Response time is excellent. Which is what I expected from a 1ms screen. It's perfect for fast pace FPS gaming. I watched a movie on it and was able to see again some cross color artefacts.

Bottom line - speaking of response time and speed.

The ViewSonic VX2739WM screen has 3 speed settings.
-Normal
-Advanced
-Ultra Fast

The manual provides no technical information about them.
It just say: normal, faster, fastest.

My first computer had a turbo button to overclock it from 4.77mhz to 7.23mhz. This was giving me a blistering fast push good for about 5minutes of stability. Then smoke, crash and rebooted itself.

My question to our Monitor experts. What are the con's of the faster, fastest settings?
I also noticed that the monitor operates by default at 60hz and can also operate at 70hz.

Does faster/fastest speed and/or 70hz will affect the life of the monitor?
The pros are somewhat obvious.
What are the cons?

Thanks.

[MF_]

Do not buy the Dell U3011 it has a horrible input lag.
It cannot harm your monitor. The cons would be watching 23.976/25 fps movies.

[NamelessPFG]

If you're not going to be using that CRT, I'll take it! Still can't beat one of those for gaming, when they work properly.

(Unfortunately, the shipping costs will shoot the price through the roof...)

It also sounds like you bought a TN panel-the Viewsonic, that is. (Color shifts along the vertical are gonna suck, but maybe you won't notice. Maybe.) Those speed settings may have something to do with how much overdrive or post-processing is applied.

[BucklingSpring]

Hmm... this review said absolutely no bleed.

Bummer - this is on my shopping list.

You didn't read my book :-)
The U3011 doesn't bleed. But It's not the one I ended up with.
The "critic" applies to the Viewsonic VX2739WM I bought instead!

The U3011 will please anyone who can actually appreciate it's quality.
But as my wife pointed out. There no point for me to get one since I'm slightly color blind.

[BucklingSpring]

If you're not going to be using that CRT, I'll take it! Still can't beat one of those for gaming, when they work properly.

(Unfortunately, the shipping costs will shoot the price through the roof...)

It also sounds like you bought a TN panel-the Viewsonic, that is. (Color shifts along the vertical are gonna suck, but maybe you won't notice. Maybe.) Those speed settings may have something to do with how much overdrive or post-processing is applied.

If you want it. I'll give it to you for free. Still works very well.
As you said... You will have to pay for the shipping.
It's a Samsung 1200NF.

[BucklingSpring]

Do not buy the Dell U3011 it has a horrible input lag.
It cannot harm your monitor. The cons would be watching 23.976/25 fps movies.

Talking to ripster  or to to me?
Isn't 24fps the human eye refresh rate?

Do you own a U3011?
According to the reviews, watching movies is no issues with the U3011
TFT Central take on the U3011
These guys seam to know their sh!t.

[keyb_gr]

The screen has 3 speed settings.
-Normal
-Advanced
-Ultra Fast

The manual provides no technical information about them.
It just say: normal, faster, fastest.

[...]

My question to our Monitor experts. What are the con's of the faster, fastest settings?

This probably controls Overdrive. Without this application of control theory, you wouldn't have a "1 ms" (gtg, I guess?) monitor there.

The basic idea is quite simple: A pixel normally exhibits a certain step response when going from one brightness level to another, usually exponential with a certain time constant. This can cause visible blur. Now for every step response there is an impulse response. If one could pass the image signal for each pixel through a system with a transfer function that is exactly the inverse of the pixels', the total impulse response would be unity and step response would be perfect.

Of course, it doesn't work quite as perfectly in practice. Here you can choose your step response between well-behaved with no or very little overshoot but slower, or faster with varying degrees of overshoot. Too much overshoot will cause halos around moving objects.

With a monitor of 2560 x 1600 pixels, an input lag on the higher side of things doesn't surprise me a whole lot. After all, twice as much data needs to be processed vs. a "Full HD" 1920x1080 screen, and three times as much as on a classic 1280x1024 job.

[BucklingSpring]

This probably controls Overdrive. Without this application of control theory, you wouldn't have a "1 ms" (gtg, I guess?) monitor there. (...)

Of course, it doesn't work quite as perfectly in practice. Here you can choose your step response between well-behaved with no or very little overshoot but slower, or faster with varying degrees of overshoot. Too much overshoot will cause halos around moving objects.

In other words faster only causes more overshoot (image quality).
So it shouldn't affect the durability of the screen. Right?

How about the refresh rate, does a faster refresh rate shorten the life of LCD pixels?

Thanks.

[Jerri]

This probably controls Overdrive. Without this application of control theory, you wouldn't have a "1 ms" (gtg, I guess?) monitor there.

The basic idea is quite simple: A pixel normally exhibits a certain step response when going from one brightness level to another, usually exponential with a certain time constant. This can cause visible blur. Now for every step response there is an impulse response. If one could pass the image signal for each pixel through a system with a transfer function that is exactly the inverse of the pixels', the total impulse response would be unity and step response would be perfect.

Of course, it doesn't work quite as perfectly in practice. Here you can choose your step response between well-behaved with no or very little overshoot but slower, or faster with varying degrees of overshoot. Too much overshoot will cause halos around moving objects.

With a monitor of 2560 x 1600 pixels, an input lag on the higher side of things doesn't surprise me a whole lot. After all, twice as much data needs to be processed vs. a "Full HD" 1920x1080 screen, and three times as much as on a classic 1280x1024 job.

For myself, your post nailed it, Keyb_gr ! :amen:

And if i'm correct 24fps looks like smooth motion for the human eye, of course you can see more (the maximum is different from one human to another), but you need only 22 (if my biological teacher was correct back than) to get a natural motion.

[godly_music]

As I understand it, without response acceleration LCDs hit a wall at around 4ms response time. Which is still pretty low, and you can probably play shooters just fine. So it would be better to not use that technology and sit on 4ms rather than use a possibly flakey technique, have 1ms response time and see some weird artifact every time the pixels change suddenly. My old monitor did that. No, it wasn't too subtle.

[Arc'xer]

Talking to ripster  or to to me?
Isn't 24fps the human eye refresh rate?

The human eye will see whatever the hell it wants to see. The human eye is constantly streaming stopping only when you blink. The whole 24-30FPS limit thing is pure bull**** propagated by console gamers and or people who can't afford equipment(computer, monitor etc.etc.). Or they are just completely blind and oblivious to the differences.

I mentioned this before but back when people had high-end CRT. Some gamers would play at such high refresh rates that they could guesstimate refresh rates, we're talking about refresh rates around the 140hz-160hz+. Even some can detect not just judder from the improperly formated blueray films(23.976p instead of the proper 24p with an equal refresh rate divisor such as 143.856hz/23.976p or 144hz/24p, in the judder case 144hz/23.976p would create a frame hiccup) but some can even detect small dips in frame rate while gaming(ex. 60fps constant and a small 2-3fps drop).

For myself, your post nailed it, Keyb_gr ! :amen:

And if i'm correct 24fps looks like smooth motion for the human eye, of course you can see more (the maximum is different from one human to another), but you need only 22 (if my biological teacher was correct back than) to get a natural motion.

Persistance of vision

How about the refresh rate, does a faster refresh rate shorten the life of LCD pixels?

It's hard to say yes or no. Because the panels made for 120hz LCD(shame they couldn't squeeze out an extra 5Hz for 125hz so it can match the polling rate of your mouse (125Hz/250Hz/500Hz/1000hz)) were built with the capability for that refresh rate. Generally when you pushed either an LCD or CRT it will black out and display on the OSD("Signal out of range").

In a way I guess you can say yes it does shorten it. Logically it makes sense your utilizing the panel at a faster rate. But it's hard to completely say yes if it was made for such purpose.

And either way much like overclocking computer equipment. Even if it does shorten the life of the panel in many cases your better off using the equipment at it's maximum now rather than saving it and somehow expecting it that 5-10-15 years down the road your fine.

(OT: Speaking of refresh rate not all LCDs can push past 60hz. Many will provide a false signal and while it may seem like it's 72hz/75hz/85hz/90hz, it's actually 60Hz with judder(the panel will reduce it back to 60). But there are real overclocking monitors such as the 2209WA(75hz-76hz) or the Flatron L227WTG(85hz-86hz))

As I understand it, without response acceleration LCDs hit a wall at around 4ms response time.

I mentioned a little bit on the response time in a previous thread.

Overdrive has it's limit and while it can provide zero input lag and reduce response time, your gonna get artifacting.

4ms would most likely be certain shades of colors, GtG, WtW, and BtB. But that's not for every color and LCDs depending on the shade of color and the color itself can be as fast as the refresh rate or as slow as the refresh rate + the pixel change period(anywhere between 30-150ms), so that's 16.6666667 + response time(30-150), would be 45-165 and that's ignoring input lag.

As for LCD monitors they've pretty much hit their limit a couple years ago. Unless your hoping for the experimental blue-phase panel to pop up, it's the inherent limit of the technology one among many other limits.

[BucklingSpring]

(OT: Speaking of refresh rate not all LCDs can push past 60hz. Many will provide a false signal and while it may seem like it's 72hz/75hz/85hz/90hz, it's actually 60Hz with judder(the panel will reduce it back to 60)

AFAICT The ViewSonic VX2739WM is capable of 70hz. I tried it and noticed the difference. But the image got somewhat distorted (just like it uses to do on CRT's when playing with the refresh rate). But I didn't feel like retweaking the size, the position and all the other messed up things due to the new refresh rate. So I switched back to 60hz.

I don't want to enter the eye FPS debate. But LCD's and CRT don't seam to display hz the same way. I can't stand a CRT running at 60hz, the flickering drives me nuts. On a CRT, I start to see a solid image at 85Hz and can't notice the difference beyond that. On the other hand, a LCD running at 60hz doesn't bug me at all. I suspect it's probably because of the image retention of a LCD. ie the previous image is still there when the new one overwrites it. As opposed to a CRTs where you have "gaps" between images.

[Quest-]

AFAICT The ViewSonic VX2739WM is capable of 70hz. I tried it and noticed the difference. But the image got somewhat distorted (just like it uses to do on CRT's when playing with the refresh rate). But I didn't feel like retweaking the size, the position and all the other messed up things due to the new refresh rate. So I switched back to 60hz.

I don't want to enter the eye FPS debate. But LCD's and CRT don't seam to display hz the same way. I can't stand a CRT running at 60hz, the flickering drives me nuts. On a CRT, I start to see a solid image at 85Hz and can't notice the difference beyond that. On the other hand, a LCD running at 60hz doesn't bug me at all. I suspect it's probably because of the image retention of a LCD. ie the previous image is still there when the new one overwrites it. As opposed to a CRTs where you have "gaps" between images.

This is because the lighting of a LCD screen runs at 200hz static(atleast the normal ones not the ones wich are LED backlit), so you dont get the flickery effect CRT's have when you change the refresh rate.

Most ppl think for this reason a higher refresh is unimportant on LCD screens. It does however influence how smooth motion is shown on the display. If i ever bought a LCD screen myself, it would be atleast a 120hz model.

Im using a Sony F520 CRT as main screen atm. 1280x960 @ 137hz, amazing for fps games

and once i have motion interpolation set up properly in my player it should make a big difference also

PS: theres articles stating the human eye can go up to 500fps, i can notice the difference between 120 and 137hz, but that may be because the area of your retina that is not in the center can perceive motion much faster, so my eyes would only notice the less flicker and not the added smoothness. But thats just a theory

PS2: love your cat

[BucklingSpring]

Im using a Sony F520 CRT as main screen atm. 1280x960 @ 137hz, amazing for fps games

PS2: love your cat

That Trinitron was a fantastic monitor. I'd buy another one without even thinking if they were still available. Those dinos were at the peak of the CRT technology.

Here's couples of other shots at my furry monster. It's a 5 year old Burmese.

5 months


2 years


Wife teasing him


Cat response

[keyboardlover]

CAMEL TOE ALERT!!!!

Cute ****.

[BucklingSpring]

CAMEL TOE ALERT!!!!

Cute ****.

You're bad... :nono:

I should have said EX.

So she is somewhere out there looking for a smart guy like you who's going to seduce her with fancy humor.

Btw if she kicks you in the face, it means she likes you.

[elbowglue]

The human eye will see whatever the hell it wants to see...

Arc'xer you are the bomb.  I have a total man-crush on you.  Ok maybe that last part isn't totally true.

Seriously anyhow thanks for your thoughtful posts, I highly appreciate the time you put into your responses.

/end asskissing

[pm_]

This is because the lighting of a LCD screen runs at 200hz static(atleast the normal ones not the ones wich are LED backlit), so you dont get the flickery effect CRT's have when you change the refresh rate.

Part of this is also because the pixels on an LCD are on or off, so when you have a static image on the screen, the pixels are always on. The only thing then that would then affect refresh, as you said, is the backlight.

When the pixels start changing, that's when the god awful 60 Hz refresh rates become apparent.  Show the right content, and I bet the vast majority of people could easily see the difference between 60 and 120 Hz, with a lot of people being able to discern higher refresh rates.

60Hz is so trash, just like most consumer LCD panels today.  While 120Hz panels are rare and pricey in relative terms, I think they should be the starting point.  The marketing tools are too lazy in the PC Monitor business and don't realize how to show the advantages of 120Hz displays and sell them. The market is so lacking in innovation. I hope that changes.  But hey, they're also the same tools that have been marketing 1080p displays to your average joe, when it's inferior to a 1920x1200.

Bastards!

[BucklingSpring]

The marketing tools are too lazy in the PC Monitor business and don't realize how to show the advantages of 120Hz displays and sell them. The market is so lacking in innovation. I hope that changes.  But hey, they're also the same tools that have been marketing 1080p displays to your average joe, when it's inferior to a 1920x1200.
Bastards!

LoL... The world is upside down.

Not long ago, PC Monitors were much better than TV's. Now it's easier to find a 120Hz TV than a monitor. Might have something to do with the 3D gold rush.

[keyboardlover]

You're bad... :nono:

I should have said EX.

So she is somewhere out there looking for a smart guy like you who's going to seduce her with fancy humor.

Btw if she kicks you in the face, it means she likes you.

Lol sorry...I just couldn't help it!

BTW, the "nice ****" and "do want" comments are about the cat! I was just pointing out the cameltoe. Im not THAT bad!

[MoB]

Btw if she kicks you in the face, it means she likes you.

Sounds like my ex

[instantkamera]

Some good info in this thread,  a lot of unnecessary info, and a pinch of talking out of the ass as well...

don't want to enter the eye FPS debate. But LCD's and CRT don't seam to display hz the same way. I can't stand a CRT running at 60hz, the flickering drives me nuts. On a CRT, I start to see a solid image at 85Hz and can't notice the difference beyond that. On the other hand, a LCD running at 60hz doesn't bug me at all.

This is because the lighting of a LCD screen runs at 200hz static(atleast the normal ones not the ones wich are LED backlit), so you dont get the flickery effect CRT's have when you change the refresh rate.

Not quite, but the fact that the backlight is essentially "always on" does play a part. The OP had it right in the first place:

 I suspect it's probably because of the image retention of a LCD. ie the previous image is still there when the new one overwrites it. As opposed to a CRTs where you have "gaps" between images.

you got it. It's called "sample and hold" and it's also the phenomenon that creates the perceived reduction of resolution when displaying fast motion (motion blur).

[BucklingSpring]

Im not THAT bad!

Yes you ARE! But don't worry I was laughing too.
I'm just a b!tch trying to induce guilt for fun.

[BucklingSpring]

you got it. It's called "sample and hold" and it's also the phenomenon that creates the perceived reduction of resolution when displaying fast motion (motion blur).

Ah!!!!! Okkkkkk. I always wonder about that one.
You are right there is some good stuff in this thread.

And sorry for the other crap, I'm a bit of a troll. It's so natural that I can't even resist to do it in my own threads.

[keyb_gr]

Total lack of flicker (as you get with a standard CCFL backlight) was one of the major reasons for me going LCD at the time. When you've got a pinch of nystagmus to contend with, flickering is bloody annoying. I used to run my old CRT at 85 Hz (it would get too blurry at 100) and was still ready to call the fire department after a few hours.

I'm still on the same Samsung PVA panel with a real-life ~30 ms b/w response (that was years before Overdrive even became available, which then turned "25 ms" into "8 ms" panels). Stuff like scrolling took getting a bit used to but was fine afterwards.

[RiGS]

Hey, you have a hot wife!

[Artillery]

I have an Acer P223W;22-inch, a Dell U2211h;21.5-inch, and my HP P1130 CRT; 21-inch tube, 19.5-inch viewable.  

For video the Dell completely wins, for gaming the CRT still takes the cake, 1600x1200@100hz and rock solid is too good for me to give up.  The Acer is well, crap really.  It has no problems with input lag, but pixel response on the dell is smoother and it also has bleed problems.  It is still a good monitor for what I paid for it, but TN-panel LCDs just look so bad compared to IPS-panels after you spend some time with them.


If you still use a CRT make sure its a good one, the Trinitron is still the best type of CRT ever made.  Sure its bulky and puts out alot of heat, but I miss it when ever I am up at college.  Its so good to game on, you can tell the difference between 60hz and 120/100hz and it is just strange how smooth it looks while still being very sharp.

Also the stuff about the framerate the eyes see at is very different from what is real.

--Test 1: Smoothness of motion--


Imagine yourself watching movie of an unbelievably slow fog. You don't see edges and sharp borders. Now play the movie with 10fps. It will look fluid. Why? Because the difference from one frame to the other is very low. The extreme would be a totally unmoving wall: Then 1 fps would equal 1000 fps.

Now take your hand and move it slowly in front of your face. Then move it faster until it's blurry. How many frames per second do you see? It must be little, because you see only a blurred hand without being able to distinguish every change per millisecond, but it must be many, because you see a fluid motion without any interruption or jump. So this is the eye's trick in both examples: Blurring simulates fluidity, sharpness simulates stuttering. (It's similar to "rotation simulates gravity".)

The fact is that the human eye perceives the typical cinema film motion as being fluid at about 18fps, because of its blurring.

If you could see your moving hand very clear and crisp, then your eye needed to make more snapshots of it to make it look fluid. If you had a movie with 50 very sharp and crisp images per second, your eye would make out lots of details from time to time and you had the feeling, that the movie is stuttering.

Just think of modern games: Have you ever played Quake with 18fps? There is no motion blur in those games, thus you need a lot of frames per second more.

However, you see the spots and the dirt of single frames in a cinema film, don't you? And those movies are played at 24fps. So there is a difference between seeing motions fluid and seeing that there's something (dirt) at all. Read on.

--Test 2: Sensitivity to darkness--

Imagine you look at a shining white wall. Now this wall turns totally black for 1/25th of a second. Would you notice it? You surely would. 1/50th of a second, well maybe harder. 1/100th of a second? Very difficult. Think of your 100Hz TV sets. They are called flickerfree, because at flicker rates of 100 times per second you stop to notice the blackness of the TV screen, though the TV screen isn't shining all the time, but pulsating 100 times per second. Brightness eats darkness.

Take again "Test 1: Smoothness of motion". You have a fluid film with 24 fps. The film roll has to roll thru the projector. To not see it rolling you have to make the picture black while the film rolls on. You would have to blacken the screen 24 times per second. But 24 black moments are too visible. Thus you have smooth motions but flicker.
The solution is: Show each frame 3 times and make the screen black 3 times per frame. This makes the black moments shorter and more frequent: "Triple the refresh rate". So you see about 72fps in the cinema, where 3 consecutive frames are the same. Strange solution? Solution of an analog world. And an example how "Brightness eats darkness".

--Test 3: Sensitivity to brightness--

Let's do the opposite test to "Sensitivity to darkness". Let's talk about, how sensitive the eye is to brightness.

Imagine yourself in a very dark room. You have been there for hours and it's totally black. Now light flashes right in front of you. Let's say as bright as the sun. Would you see it, when it's only 1/25th of a second? You surely would. 1/100th of a second? Yes. 1/200th of a second? Yes. Tests with Air force pilots have shown, that they could identify the plane on a flashed picture that was flashed only for 1/220th of a second.

That is identifying. So it's pretty safe to say, that recognizing, that SOME light was there is possible with 1/300th of a second. Now if you take into consideration, that you have two eyes with different angles and different areas of sensitivity (you probably know, that you see TV flickering best, when you don't look directly into the TV screen, but with the sides of your eyes) and you can move/rotate/shake your head and your eyes to a different position, you probably needed flashes as short as 1/500th of second to make sure, nobody sees them in any case.

Now, what happens if I flashed you 1/500th of a second once in a second for 365 days directly into your eye? Would you feel something strange? Would it feel different than without it? Would you notice that something is wrong?

So, we should add a security value, to make sure nobody sees ANYTHING even unconsciously and feels comfortable about it.

Maybe the industry didn't add enough security factor to CDs and that's why many people still feel that analog is sometimes better. It's like in a room full of neon lights. You just know that something isn't right.

[keyb_gr]

Interestingly enough, hearing behaves in a similar way. Hearing a narrow dip in the frequency response? Pretty hard. Hearing a narrow spike? No problem. A short dropout also is unnoticeable most of the time, but some kind of crackling usually is not.

If I were stuck with a CRT, I'd run it with some kind of inverse theme. Big bright areas make flicker noticeable easily.

[panda-R]

Btw if she kicks you in the face, it means she likes you.

i love getting kicked in the face! It's almost as enjoyable as falling out of trees.

[Surly73]

That Trinitron was a fantastic monitor. I'd buy another one without even thinking if they were still available. Those dinos were at the peak of the CRT technology.

I've got two pretty minty GDM-F520s in boxes which I've owned since new that I'm thinking it's about time to get rid of.  I used one at the office and one at home until a few years ago.  I got a "meh" LCD at work but it freed up a ton of desk space and greened up my carbon footprint a bunch.  I got an NEC LCD2490WUXi for home and haven't looked back.