Samsung SA850 on PLS - the first review has been published (preproduction unit)

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albovin

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Samsung SA850 on PLS review (preproduction unit).

What the review says:
- very good viewing angles (still no information if it has colorshift or not)
- relatively low contrast ratio (seems to be a mistake in measurements)
- poor uniformity (deviations up to 45%)
- crystalline effect (AG coating) isn't more noticeable that on an average TN
- no HDMI (which if connected through DVI will be 1920x1080 only)
- response time 7,3ms average GTG, 13ms max (same as e-IPS) at "Normal" mode ("faster" modes increase ghosting)
- default gamma setting leads to some black crush (played with gamma control to improve the situation)
- color gamut is slightly larger than sRGB
- angle LCD glow is somewhat similar to e-IPS but less pronounced

Overall impression: not ideal but positive.
 
I wish samsung still made more true S-PVA panels as in my opinion i find those to look best for my use. I like the great contrast and the Color shift is minimal and definitely better than the new c-pva ones. Theres also zero off angle glow. I had an H-IPS panel and got rid of it because I found the contrast to be crap, and the off angle glowing annoyed me like crazy.
 
It looks like a defective unit, or at least you'd hope so. Otherwise it seems more like an alternative to TN rather than a real competitor with IPS.

Calibrated Color accuracy (moderate corrections needed, major blue deficiency in shadows), Calibrated Contrast Ratio (371:1 - 535:1), Calibrated Black Level (0.27 cd/m2 - 0.59 cd/m2), Uniformity (intense backlight bleed) are all sub-par. At the very least it suggests that Samsung's PLS panel build quality may be worse than LG's already marginal IPS build quality. Even if the likes of PRAD and TFT Central get defect-free PLS panels for review, early-adopters should be wary (buy from someplace with a hassle-free return policy) until defect rate is more well known.
 
> Samsung's PLS panel build quality may be worse than LG's
> already marginal IPS build quality.

> until defect rate is more well known

Ok, I'll bite. What *is* the defect rate on the LG IPS panels?
Do all models of LG IPS panels have pretty much the same defect rate?

Is the defect rate on Panasonic IPS panels known?

Does anyone else make IPS panels?
 
^^^Should fix some of those problems - as the reviewer seemed to think the low contrast test numbers were caused by bad uniformity.

OTOH the main advantage of this monitor seems to be cost and the lack of strong AG coating..
 
That's certainly discouraging. I'm going to withhold judgment (both of the purchasing and panphleteering variety) until after a production unit is out. The panel uniformity issues are probably a function of the manufacturing process, which presumably wasn't set for that unit.

Is there really no displayport connection? Irnoically, that might be my ultimate deal breaker.
 
The testing methodology looks the same as that one other US site who's contrsat/black measurements are always no where near reality (extremely low). Serisouly 0.27cdm/2 black at 100cdm/2 brightness...this is a number you would expect to see from a 2005 monitor. Take this reviews CR measurements with a grain of salt.

Other wise it is fine, glad to see the low response time numbers and good viewing angles.
 
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Hmm, the contrast numbers do seem wrong. Everything else looks promising apart from the terrible uniformity. The fact that their unit has strong backlight bleed at the exact same place as the one we've seen in one of previous pictures is a bit worrying.
 
Walker said:
Hmm, the contrast numbers do seem wrong. Everything else looks promising apart from the terrible uniformity. The fact that their unit has strong backlight bleed at the exact same place as the one we've seen in one of previous pictures is a bit worrying.
Click to expand...

Maybe it is the same actual display?
 
My expectations about PLS.

1. Viewing angles same or little better than on IPS.
Reality: still to be confirmed but seems to be true. I don't want to believe that PLS did not get rid of annoying PVA colorshift.

2. AG coating is less aggressive.
Reality: AG coating it's not a part of LCD techlogy, but at least for the new panel less AG coating is confirmed.

3. Black level from 0.1 cd/m2 and CR up to 1000:1
Reality: as I mentioned at the beginning, measurements provided by the reviewer (actually this is X-bit Labs) seem to be wrong. It's still possible that PLS will be close to expected values.
Assuming viewing angles are perfect, 0.15 and 850:1 will be wonderful.
Color gamut (larger than sRGB) provokes some concern.

So the technology itself looks promising.

Other considerations.
Built quality and good factory settings weren't expected from this manufacturer.
PLS seems to be a slightly improved version of e-IPS.
It would be nice to see a real PLS monitor made by NEC (with CCFL backlight, no LED experiments please) or it's economy version made by Dell.

Just speculation.
Why is the Samsung SA850 delayed?
They cannot produce any significant number of quality units (?)
 
Not too bad for a first review. No AG coating bothering is a go. I'm also pretty certain that the black levels won't be an issue, even modern TN panels have halfway decent black levels at the center of the screen. Backlight bleed and viewing angles are the last two bits missing for a "perfect" display. But no review will be able to guarantee me that the viewing angles are ok. They said that about IPS in almost every single review, and still the viewing angles or IPS are nowhere near perfect. Looks like I'll have to make another trial and error order.
 
Samsung knowingly sent a defective unit with horrible screen uniformity and backlight bleed to a review site that will be read thousands of times. Either this is a very bad marketing strategy or people are already trying to rationalize this monitors shortfalls.
 
cvgd said:
That's certainly discouraging. I'm going to withhold judgment (both of the purchasing and panphleteering variety) until after a production unit is out. The panel uniformity issues are probably a function of the manufacturing process, which presumably wasn't set for that unit.

Is there really no displayport connection? Irnoically, that might be my ultimate deal breaker.
Click to expand...

There is displayport. You can see the connector in the pictures.
 
Input lag?

I notice significant less white-glow compared to IPS.
 
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stimuli said:
Samsung knowingly sent a defective unit with horrible screen uniformity and backlight bleed to a review site that will be read thousands of times. Either this is a very bad marketing strategy or people are already trying to rationalize this monitors shortfalls.
Click to expand...

Ya I'm not buying it either. I think Samsung developed PLS monitors thinking they could grab some main stream market between TN and IPS. Since then though e-IPS has emerged and probably leaves Samsung out in the cold.
 
stimuli said:
Samsung knowingly sent a defective unit with horrible screen uniformity and backlight bleed to a review site that will be read thousands of times. Either this is a very bad marketing strategy or people are already trying to rationalize this monitors shortfalls.
Click to expand...

perhaps we should wait for a few reviews of production models before jumping to conclusions? :rolleyes:
 
^^^It's a preproduction unit..<g> It says so right in the review. I expect better (but not great) uniformity in the production model but we will see..
 
albovin said:
Just speculation.
Why is the Samsung SA850 delayed?
They cannot produce any significant number of quality units (?)
Click to expand...

I would be stunned if the tsunami didn't have some impact. I don't know about this panel in particular, but much of Samsung's lcd tech is co-manufactured with Sony. Even if the Korean peninsula was relatively untouched, disarray in Japan could complicate things.

Many of the timelines proffered in January/December have been off.
 
Whats the point of sending out a monitor that's not ready for prime time? I would think that they should send a proper panel to show off PLS at its finest. Time will tell.
 
stimuli said:
Whats the point of sending out a monitor that's not ready for prime time? I would think that they should send a proper panel to show off PLS at its finest. Time will tell.
Click to expand...

Obviously they have not.

This is similar to when music, games and such are leaked prerelease. Someone has done something illegal to get it/review it.
 
Oled said:
Obviously they have not.

This is similar to when music, games and such are leaked prerelease. Someone has done something illegal to get it/review it.
Click to expand...

I'm going to have to agree with this.

I would just like to know the price, and honestly I would have to see one in person. There are certain defects I can live with, ag coating I can, color shift drives me nuts.
 
Panel a side, Aesthetically and functionally, I like it a lot.

It looks like it can even pivot into portrait fairly easy.

If this helps bring down cost by any means I think it will be a success. Of course if it's pure crap we'll know too.
 
this thread, like the last multi-paged one devoted to it have just turned into pointles speculation, and should be merged.
 
alienate said:
Ya I'm not buying it either. I think Samsung developed PLS monitors thinking they could grab some main stream market between TN and IPS.
Click to expand...

They or some other developers should just reinvent the TN tech in a way that fixes the vertical gamma shift. Because that's much more of a problem than the viewing angles.
 
And can you think of a way of eliminating the twisted nematic grey-scale inversion? Do you know what causes it? Do you know why IPS and MVA do not suffer from the same effect?
 
Why ask me? Obviously it's the limitation / part of the tech, but as to the specific reason of why it happens, ask someone who knows the inner workings of the TN technology. As for the last bit, what kind of question is that? They're not TN in the first place, so why should they suffer from problems caused by TN?
 
Tamahagane said:
They're not TN in the first place, so why should they suffer from problems caused by TN?
Click to expand...

Well they are all based on nematic liquid crystals. I mentioned MVA as it is a good exercise on the TN problem because it aligns out of plane yet does not invert like TN.
 
VA would be "perfect" (very big quotation marks) if it wasn't for the gamma shift (the nature of which is more annoying than Vertical Gamma Shift on a TN)... but then it wouldn't be VA, and TN wouldn't be TN without the VGS, and IPS won't get A-TW polarizers, and other issues. The entire LCD tech is broken from the beginning and can't be fixed. It can easily be made a bit better but there's no money to be made in that vs continuing selling it like it is now.
 
Tamahagane said:
It can easily be made a bit better but there's no money to be made in that vs continuing selling it like it is now.
Click to expand...

Oh, stop your conspiracy theorist bullshit that everyone is a dumb sheeple and companies are intentionally not innovating to save money. If you had ever looked at a serious display related news source, you would have found that future profits are largely predicated around major innovation and making old technologies obsolete. It is a joke opinion to say that the display industry is somehow anti-innovation.

The very opposite of your claim is true.
 
Who killed the electric car?

Wow, I hope you're not serious because if you are... well, it's not my problem. Still though, quite amazing.
 
Tamahagane said:
Who killed the electric car?

Wow, I hope you're not serious because if you are... well, it's not my problem. Still though, quite amazing.
Click to expand...

Wow, that needy, attention seeking CT one-liner on an unrelated topic really demolished my argument there. Not like I can refute that without crapping the thread, even though it is deliberately framed as a question to avoid your burden of proof, to make me do all the work, and to drag me in to a selfish argument.
 
Tamahagane said:
They or some other developers should just reinvent the TN tech in a way that fixes the vertical gamma shift. Because that's much more of a problem than the viewing angles.
Click to expand...

The did and it is called IPS/PVA/MVA/PLS etc....

TN was first and everything since has been a variation on crystal structure to improve TNs issues.
 
sblantipodi,
Relax.
TFT Central is just reposting what we have talked here.
 
Another thing the review says is brightness regulation with PWM at 180Hz.
Any opinions if this is enough to be comfortably invisible?
 
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