Dell S-Line Screens - S2740L, S2440L, S2340M, S2340L, S2240M

Okay, so which one would be the best option for me? S2440L (AMVA) or U2312HM (IPS) or new AOC i2367fh (IPS) monitor?
My preference is it should be great for movies and games.
 
just got my s2440L A00 rev aug 2012 manufacture im using hdmi to hdmi cable.

below are the cons only.

1. it has pwm. im using R 44 G 42 and B 38 and brightness 100 contrast 75 to avoid pwm.
2. gamma shifts are quite a bit in amva... greys have a blue hue in one part of the screen and green in another. 6 inches horizontally one color of grey and the next 6 inches another color of grey unless you are looking dead straight.
3. 16:9 is funny wide.way too wide. but nothing against it. being too wide doesnt help gamma shifts either. you can get used to it if color shifts werent as bad in amva.
4. text mode isnt useful for me. im using standard mode with cleartype off. looks best in standard mode.

on the positive note reflections arent bothersome at all when indirect light falls on the screen.
i'll keep it for another 2 days for testing as my main monitor. if anyone wants to know anything please ask.
 
hi all.

dell could face a terrible confrontation, I am beginning to wonder about!

there seems to be two camps here with the s2440l.

one, a beautiful screen with no PWM.
two, PWN, often in a terrible manner, with problems with color shiftings and other "not-so-good" stuff.

I am beginning to wonder if Dell, in its subcontracting to other makers, has a certain manufacturer making their panels with much poorer quality?

I say this, and I wish that I could find the actual post on it, i tried for ten minutes to no avail, but on one of these posts, i think it was the catleap thread, that it was said that there were several panel sub-manufacturers and while one or two of them were of good quality, one of the makers gave a panel that might as well be a cheap tn panel with poor color and contrast! And no way to tell in the store or on-line! the "panel lottery", they call it!

Dell could find itself in VERY hot water over this and maybe they have no idea that some of their panels might even be a "counterfeit" in disguise!
The word gets out and they fail to impress and down they go.

freestone
 
thats true freestone. some have pwm some dont and that is NO good for dell.

but on the positive side the pwm effect is easily avoidable since the monitor isnt too bright to begin with.
I found the following settings to better help with gamma shifts and keep pwm at bay.
brightness 100
contrast 40
R - 99
G - 92
B- 92.

this reduces the gamma shift considerably compared to the previous settings and gets rid of the PWM.

But on a side note gamma shift seems to be a worse thing to deal with than viewing angles. Even a TN panel has more uniform gamma looking straight on than this technology.



Also can you check the pixel inversion pattern 4a and 4b on lagom.nl http://www.lagom.nl/lcd-test/inversion.php#invpattern

with 4a i get horizontal lines running down the screen and 4b causes pulsing. is it the same for your panel?
 
sounds more likely to be a simple (and fairly common) panel lottery, with perhaps a couple of different panels being supplied within spec for the screen and then used in different stocks and manufacturing lines. It might even be two slightly different, but very similar versions of the same panel from AU Optronics, but it will all be well within spec and something which many manufacturers do. No conspiracy theory and Dell wouldnt get in trouble for it at all, it's perfectly normal. It does of course make it a little tricky for the consumer as they dont know which version they are getting, if there are indeed 2 different versions.

Remember back to the days of the Samsung 226BW which had 3 different panel manufacturers (CMO, Samsung and AU Optronics) all supplying panels for the same screen!? at least here we know they are all AMVA panels (or certainly should be) and so should all be supplied by AU Optronics. we know what panel was used in the PWM-free TFTCentral review units as theyve confirmed that, now we need someone with a supposedly "bad" unit showing PWM to take the back off and confirm for us if there is a difference!

Could shifting is related to the AMVA panel technology and i've seen no reports suggesting that is any different on the so-called different versions. and i havent see any other "not-so-good" things that you mention. so far it seems only that there might be some using PWM, and some which don't.
 
after seeing the huge amount of contrast range to play with in amva panels i dont think pwm is a big deal in this technology. you can easily make brightness 100% and lower contrast to eliminate pwm without affecting colors too much. but that is not possible in IPS or TN where contrast ratio is poorer and contrast range is much smaller.
 
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Is there any other way than using a camera to check if my monitor has PWM ? If it does then it's not a problem for me, but I want to be sure before buying the S2440L. The monitor I'm talking about is LG W2284F (LCD).
 
l33twannabe said:
Is there any other way than using a camera to check if my monitor has PWM ? If it does then it's not a problem for me, but I want to be sure before buying the S2440L. The monitor I'm talking about is LG W2284F (LCD).
Click to expand...

are your whites/greys in LG slightly yellow? if so then you have the same panel as in my hp 22". yup camera high shutter speed (sports mode) is the easiest way to check for pwm.
 
Is PWM part of the panel itself, or part of the monitor's electronics? I assumed it was the latter, but I am just guessing there. Just wondering if the panel version would even matter if the PWM electronics are on an internal board instead, not the panel itself.

As for horizontal color shift, how much leeway would you say you have before the colors start to noticeably change? Would turning your head slightly cause a color shift? If you sit relatively straight on, do you see color shift at the edges of the screen? The only VAs I have seen are VA/S-PVAs either in 4:3 or 5:4, and color shift isn't too terrible... but even on a 21.3" S-PVA, the horizontal shift starts to creep in if you move your head too much.

It sounds like the the 24-27"er AMVAs may be best served as gaming/tv monitors, if you sit several feet away and relatively straight on. Anyone out there use them with photoshop or anything that does rely on mostly accurate colors? Not professional work, I mean just everyday normal stuff.
 
namelessme: with brightness up and contrast down you see the worst of amva gamma shift. but that is only to avoid pwm. if pwm is not an issue then keep contrast up and brightness down and the leeway is as good as any other technology.
 
Ah, I must have misread your post. I thought you meant at the settings you put it at (high brightness/low contrast) the gamma shift was improved over stock levels. You meant just compared to what you originally set it at.

If it was me, and I was that sensitive to PWM, I might suggest playing the return game. Just return/rebuy until you get a PWM free one.
 
dopple said:
are your whites/greys in LG slightly yellow? if so then you have the same panel as in my hp 22". yup camera high shutter speed (sports mode) is the easiest way to check for pwm.
Click to expand...

Just took a video (with my phone, iso set to 400) of my monitor and I can clearly see those horizontal lines going up and down. It doesn't look too agressive, but I guess it's a matter of a proper equipment which I don't have. Anyway, is it a proof of my monitor using PWM or should I check it with some better camera before jumping to such conclusion ?

EDIT: Yes, it must be PWM. When I set brightness to 100%, those lines disappear. That means it doesn't really matter to me as I don't notice it at all.
 
l33twannabe said:
Just took a video (with my phone, iso set to 400) of my monitor and I can clearly see those horizontal lines going up and down. It doesn't look too agressive, but I guess it's a matter of a proper equipment which I don't have. Anyway, is it a proof of my monitor using PWM or should I check it with some better camera before jumping to such conclusion ?

EDIT: Yes, it must be PWM. When I set brightness to 100%, those lines disappear. That means it doesn't really matter to me as I don't notice it at all.
Click to expand...

unless im looking for it i cant see it either but i can feel the effects now that they've been pointed out too :D plus when you're in the market for a new monitor its best to buy a pwm free monitor .... http://www.essex.ac.uk/psychology/overlays/2010-195.pdf

check out the effects of invisible flicker in that paper.
 
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Namelessme said:
Ah, I must have misread your post. I thought you meant at the settings you put it at (high brightness/low contrast) the gamma shift was improved over stock levels. You meant just compared to what you originally set it at.

If it was me, and I was that sensitive to PWM, I might suggest playing the return game. Just return/rebuy until you get a PWM free one.
Click to expand...

yep will be exchanging this panel in 2 days. will have some fun with it before sending it back in. :D
 
I always wondered about eye strain and flicker -- even FRC flicker. It may not bother people on a short term basis, but if you use your monitor for hours on end, daily... for months and months... it logically could cause additional eyestrain.

Besides some Dells (maybe) what are the other PWM free models out there? I believe the 27" Samsung PLS is PWM free (and also insanely expensive) and Eizo just came out with a 24" model. Is that all of them?
 
Namelessme said:
I always wondered about eye strain and flicker -- even FRC flicker. It may not bother people on a short term basis, but if you use your monitor for hours on end, daily... for months and months... it logically could cause additional eyestrain.

Besides some Dells (maybe) what are the other PWM free models out there? I believe the 27" Samsung PLS is PWM free (and also insanely expensive) and Eizo just came out with a 24" model. Is that all of them?
Click to expand...

couple of cheap ones dont have flicker either like benq g2020 hd. the cheaper ones arent reviewed by the big sites. better take your camphone and check it out IRL in the stores.
 
Namelessme said:
Is PWM part of the panel itself, or part of the monitor's electronics? I assumed it was the latter, but I am just guessing there. Just wondering if the panel version would even matter if the PWM electronics are on an internal board instead, not the panel itself.
Click to expand...
Not in computer monitor panels. TV panels have it sometimes. On the other hand it seems rather common that the panel manufacturer also provides PCB boards. At least in cheaper models.
 
clonalvex said:
I have S2240M, purchased from Amazon. I have been using a 4:3 HP LP2065 IPS monitor for long time now. For every Dell wide-screen that I tried over the years, I have been able perceive uniformity issues. The viewing angle tests at Lagom LCD Test website are the best example for seeing this at its greatest degree (specifically the first image).

On my S2240M, the left side of the screen is cooler moving toward the center it is neutral and has a slightly warmer appearance on the right side. This is noticeable to a lesser extent while web browsing, but on common white backgrounds the left side almost has a feint blue tint while scanning left to right.

I am sure this appearance is affected by viewing angle. When the screen is to my left I and I am viewing at a nearly parallel angle, the entire screen appears cooler, while the opposite is true when viewing it in the same manner from the right.

I am not sure if it is a coincidence or not, but on a completely black screen the IPS glow coming from the left side of the screen is yellowish while from the right it is blueish.

I have been able to limit the intensity of what I am able to perceive by raising the center of screen to my eye level (on a stand) and increasing my normal view distance slightly (~24 inches).

I know the relevance of this is not really applicable to the S2440L due to it being a different panel type, but has anyone else with S2240/S2340 been able to perceive something similar in the quality of their screens? If this is fairly common, I am pretty sure I would be willing to settle with it, because it is such an affordable screen at ~$142.
Click to expand...

This thread is really dominated by the discussion of PWM and the S2440L. My post was somewhat overshadowed by that subject.

When viewing the S2240M through my Galaxy Nexus, I see inconsistent results. 100 and zero brightness settings have been the most consistent, with no noticeable flicker (strobe lines?). But at various other brightness levels, if I have been able to keep my camera focused on the screen while adjusting, there are increments where the lines will stabilize (no longer visible). But this is misleading, because taking the view of the camera away from the monitor and then placing it back in focus can sometimes reveal the same effect again.

In normal usage I can perceive very slight flickering in darker gradients (most often dark grays). This though is nearly imperceptible, unless I have been staring at a static image or background such as the default of this forum. I have to be really looking hard for it to become straining to my eyes.

I have a fairly long period to evaluate the S2240M. Got to love Amazon's holiday return policy from Nov. 1 to Jan. 31. I will keep my eyes on this thread, while I put more usage time into this monitor.
 
hi all.

there was a post back a while ago that told of how to check the factory settings for the panel model number. This with the dells.

but my s2440l has a different set of buttons and options, how do i get to the service settings?

I asked once and the reply person just only wrote that yes this is done.

i could not understand this. there are no buttons on the s2440l, just areas to press to bring op condensed options for the settings. so how DO I find the panel number without taking my monitor apart?!

the above explainations to me seem to explain the pwm problems well.

thank you.

freestone
 
Do U2312HM and S2340L share the same IPS panel? How is the overall quality of S2340L in comparison to U2312HM?
 
CrabJuice said:
Thanks! Summarize the answers it gave me to my own inquires:
- 300hz PWM.
- Again the aggressive overdrive with overshoot that cant be turned off.
- Very good contrast (1300:1).
Click to expand...

he equates the 300 hz led pwm with 175 hz ccfl pwm and says there is no advantage over ccfl and says at 100% brightness there is no PWM.:rolleyes:
 
freestonew said:
hi all.

there was a post back a while ago that told of how to check the factory settings for the panel model number. This with the dells.

but my s2440l has a different set of buttons and options, how do i get to the service settings?

I asked once and the reply person just only wrote that yes this is done.

i could not understand this. there are no buttons on the s2440l, just areas to press to bring op condensed options for the settings. so how DO I find the panel number without taking my monitor apart?!

the above explainations to me seem to explain the pwm problems well.

thank you.

freestone
Click to expand...

the factory menu doesnt show the panel details anymore.
 
Namelessme said:
I always wondered about eye strain and flicker -- even FRC flicker. It may not bother people on a short term basis, but if you use your monitor for hours on end, daily... for months and months... it logically could cause additional eyestrain.

Besides some Dells (maybe) what are the other PWM free models out there? I believe the 27" Samsung PLS is PWM free (and also insanely expensive) and Eizo just came out with a 24" model. Is that all of them?
Click to expand...

im not familiar with FRC flicker. any demonstration for it?
 
dopple said:
im not familiar with FRC flicker. any demonstration for it?
Click to expand...

Any 6 bit panel with FRC (to get it to 8 bit) will have it. It won't be visible to most people. In fact, I expect hardly anyone would even notice it. But it theoretically could lead to eyestrain after hours and hours... and weeks and weeks... of use. Just something I've wondered about.

It won't happen with VA panels, as they are all 8 bit anyway.
 
I thought FRC flicker is usually only visible with certain grey scale gradients, as in, if you go hunting for it when using gradient tests (lagom or Flat panels) you will find it...but not during real world use.
 
the gamma shift in greys on the s2440L panel i was talking about seems to be present on all Dell S series models even IPS. doesnt seem to be a fault of AMVa technology see the video here describing backlight leakage http://translate.google.co.in/trans...bzor_i_testirovanie_monitora_Dell_S2340L.html

you can see how blacks/greys are blue/purple and 6 inches away it is green. its easy to see when you use 100 brightness and 30 contrast setting and view this hardforums site.
 
Namelessme said:
Any 6 bit panel with FRC (to get it to 8 bit) will have it. It won't be visible to most people. In fact, I expect hardly anyone would even notice it. But it theoretically could lead to eyestrain after hours and hours... and weeks and weeks... of use. Just something I've wondered about.

It won't happen with VA panels, as they are all 8 bit anyway.
Click to expand...

NCX said:
I thought FRC flicker is usually only visible with certain grey scale gradients, as in, if you go hunting for it when using gradient tests (lagom or Flat panels) you will find it...but not during real world use.
Click to expand...

that is funny because im running a 22" 16:10 panel alongside s2440L and i can see banding on the gradient test on S2440L but when i drag the same window to the 6bit FRC panel it is free from any banding.:p
 
Dell U2312HM and new Dell U2440L. Both are of same price tag for me. Which one to choose and why?
 
NCX said:
I thought FRC flicker is usually only visible with certain grey scale gradients, as in, if you go hunting for it when using gradient tests (lagom or Flat panels) you will find it...but not during real world use.
Click to expand...

a 6-bit panel can only natively display 262144 colors. to display the other 16.6+ million colors, it must use temporal dithering. in other words, it's used pretty much everywhere all the time.

even 8-bit panels will use frc to render darker shades. has to do with non-linear response of liquid crystals with respect to voltage, or something like that.

i remember seeing this happen on an eizo s2433 (-bit s-pva, easy to see dithering in dark tones thanks to gamma shift), and when i emailed eizo support about it, they denied it. 'it's an 8-bit panel, it doesn't dither, etc etc'.
 
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Thinner displays take up less space, pack in less space. Cargo containerrs are usually fixed price.
Put more, lighter units in a container, less shipping costs, storage space.

Basically, appearently marketing says lower price/no vesa, pays off.
Economics, not hardware. Welcome to this century.
 
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