Black levels - what is real? (1 Viewer)

[andrew markworthy]

This is a question, and apologies that I don't have the technical language to make it any shorter.

By chance I saw the same episode of CSI:NY twice this week, once on a friend's plasma, and once on my own LCD.

My friend said that there were a couple of scenes that my LCD would have problems with. The first was one where two of the characters were dressed in black and the camera was shooting into the light. On the plasma, the details of the clothes were still visible. In another, a character in a dark suit moved from shadow into light and back into shadow, and the details of the suit remained distinct. Sure enough, on my LCD, the details of the clothing were more or less lost in the shooting into the light scene and the shadow parts of the other scene. [I should point out that my LCD is properly calibrated and does well on the DVE disc's pluge test - or whatever it's called].

Okay, this nicely demonstrates the superiority of plasma in handling black levels. But: how realistic is this? Please note this isn't an anti-plasma question. I'm more than happy to admit plasma's strengths. It's more a question of how true to life these black levels are.

Let's take an example - if in real life I look at someone who is standing between me and a bright light source, their details get blacked out. Likewise, if someone moves from shadow to light to back again, the level of detail I can see changes. I certainly cannot see the same level of detail as a plasma screen can 'see' in the same situation. So is this the result of the original camerawork which the plasma is faithfully reproducing, or is the plasma artificially enhancing the black levels?


[Side question: what does the 'D' badge on Garry Sinises's character's lapel signify?]

 

[RobertR]

If the shadow detail was never there in the first place, could the plasma show it? And if it is there, it seems to me the plasma is simply able to reproduce it. We all know that what's shown on screen doesn't have to be an exact reproduction of "real" life.

 

[andrew markworthy]

Robert, yes I agree about the 'not have to be real life' argument. What I meant was that the plasma (or for that matter, one of the top of the range LCDs) might exaggerate what's there for all it's worth. It looks great, but is it, for want of a better word 'hyper real'? It's a bit like those photo collages David Hockney did a few years ago where he played about with perspective - they appeared real, but they couldn't possibly have existed in real life.

It's not a grumble as much as a psychological question. The only thing I would complain about would be saying that this sort of display is more 'realistic' - it isn't. It may be more aesthetically pleasing to many people, but it ain't an accurate representation.

 

[Leo Kerr]

Andrew, a simple question:

you say your LCD is properly calibrated.

Was your friend's plasma?

Leo

 

[Patrick Sun]

The black level details is more about how each type of set illuminates the portion of the screen that has a wide difference between portions of blackness and whiteness being displayed.

LCD's use of always-on backlight makes it a tough chore to keep some parts of the LCD screen illuminated and dark at the same time without causing the display to look more washed out as a whole due to bleedthrough in light output. LCD backlight output control technology is getting better (Samsung is coming out with some fine LCD models these days), though.

Plasma sets excite individual pixels on their screen array, which gives it better control of illuminating the correct pixels on the screen, and keeping the other pixels dim to produce the intended image that was sent to it by its tuner, or other input sources.

This black level control by plasma is one of the reasons why I went with a plasma set purchase last year, plus I find LCD sets overly bright during the scenes with bright objects, or overally bright scenes, artifically so, and plasma approximates a screen display like the old CRT technology with the glass screen (not the rear-projection models) which is more pleasing to my eyes. That's a matter of personal preference, but black level performance, to me, is more consistent with the implementation by plasma sets than by LCD sets at this time (but LCD tech is catching up, though pricing is still not as attractive for the larger 50" plus LCD screen sizes).

 

[andrew markworthy]

I agree 120%. My reason for having an LCD is a simple cost efficiency issue. Because of our room layout, the largest screen that's feasible is a 37 inch. In the UK 37 inch plasmas are rare and furthermore, plasmas with Full HD specs are insanely expensive (think US prices and double them). But with a different room layout requiring a bigger screen and saner pricing, I would be perfectly happy with a plasma.

 

[Dan Driscoll]

In real life it depends on your eyesight and can vary considerably from person to person. My wife has 20/10 vision and I wear glasses, but with my glasses on I can see dark detail against a bright background much better than she can. I can also tolerate glare that will give headaches to most people, even though my glasses are not polarized.

 

[andrew markworthy]

I should have added something to this effect in my first post, so many thanks for raising it. Not least is the issue of presbyopia ('old sight') that afflicts nearly everyone after the age of forty. Basically, older adults recover from glare more slowly and also have a worsening contrast sensitivity function (basically, the minimum brightness at which comething can be seen plotted against size of image). This is in addition to problems of worsening near sight, yellowing of color vision, etc.

 

[chuckg]

I'd say there is no such thing as "real." Color is subject to all sorts of processing, and many films intentionally alter the color to affect mood. Have a look at "The Aviator" if you want a color film history lesson. See LOTR for a glimpse of carefully-controlled color processing.

Likewise, the contrast is subject to manipulation - take a look at some old BW films, you'll find some film noir that is essentially black OR white, with little between. There are many examples of films with excellent gradations of black to white, and some that seem to have a limited contrast ratio.

I guess the right answer (or question) is, does the display accurately produce what you would see in the movie theater (assuming that the theater accurately portrays the intent of the cameraman, and everyone else who has a stake)

 

[Brian D H]

Detective

 

[Allan Jayne]

1. Your friend's set might be more contrasty for black and dark grays (and perhaps less contrasty for white and light grays) while your set might be less contrasty for black and dark grays (and perhaps more contrasty for white and light grays). This difference is referred to as gamma although I don't recall off the top of my head what gamma number like 1.2 or 0.7 corresponds to what situation. Gamma may or may not be adjustable on a particular TV.

2. Those details in the dark suit might be "blacker than black". If you calibrate real black to be the darkest shade that the TV can produce, then blacker than black content is definitely hidden. Elevating (real) black subject matter to come out as dark gray may (or may not) bring blacker than black into view.

Video hints: Video Technicalia Made Easy