Medium with highest dynamic range

[Sareesh Sudhakaran]

I was curious about which medium has the greatest dynamic range for display purposes - is it paper, cloth, metal, LCD/LED, CRT or some other kind of display?

I realize color just compounds the problem - especially since each medium has its own color space, so maybe the question should be limited to greyscale tones only, sort of like in the zone system. If theoretically one has done everything possible in camera and processing to attain a printable digital file (I realize different media require different kinds of processing), especially in relation to high dynamic ranges (natural and artificially created), can it be reproduced in its entirety by any present medium?

[jeremypayne]

I was curious about which medium has the greatest dynamic range for display purposes - is it paper, cloth, metal, LCD/LED, CRT or some other kind of display?

My money is on back-light transparencies.

[Sareesh Sudhakaran]

I had a feeling that this might be the case. But then again modern MFDB systems have a greater dynamic range than slide film (but not B&W film), correct? Or am I mistaken?

Also, once the transparency is projected, is the entire DR maintained by the projection system?

[Guillermo Luijk]

Also, once the transparency is projected, is the entire DR maintained by the projection system?

The global DR can be maintained between different projection systems, it will simply get compressed to adapt to each of them, producing a loss in local contrast. You can print scenes with a large DR in real life, and the print can maintain detail in the whole luminance range, but it will project into your eyes a much smaller DR than the original scene would have.

[Ernst Dinkla]

Two sided, color dye ink printed, backlight film(s) on an adapted lightbox in a dark room.
If it can be B&W, a lith film made on an imagesetter, screening for the tones.

Straight RGB LED sign displays will be better but you need viewing distance to get sufficient resolution.

It is about creating the highest density in the dark parts, the best light transmission in the light parts, no flare caused by the backlight lamps, no flare caused by illumination in the room. Most projection systems that enlarge the image will have flare, even projecting to backlit screens. Most LCD, CRT monitor systems do not have a true black.

--
Met vriendelijke groet, Ernst

Dinkla Grafische Techniek
Quad,piëzografie,giclée
www.pigment-print.com

[hjulenissen]

Most LCD, CRT monitor systems do not have a true black.

In what way are LCD and CRT systems "black" any less true than other medias black?

To the topic starter:
Media based on modulating the reflectance (such as prints) will be limited "upwards" by a refletance of 1.0 (cannot reflect more light than it is receiving), and downwards by how low reflectance one can make (I think charcoal is in the range of 1/100 to 1/50?). Say 100:1

Media based on transmission of light have no such hard limit, but there are other practical limits (reflections from room). Be aware that quoted "1 million to one" contrast of plasma panels etc tend to be empty PR-numbers.

Like GL said, any captured scene DR can be mapped to any possible rendering DR, but for rendering high DR scenes realistically, you probably want a high DR medium.

-h

[Sareesh Sudhakaran]

I see we are not completely in agreement on film vs LCD/LED. In either case we need the darkest environment possible, and paper has the unfortunate need for ambient light. Keeping aside all other factors (like resolution), do modern professional grade monitors beat projected slide film? Isn't the projector a limiting factor?

Even though slide film might have a latitude of 13 stops, an HDR image can to 18 (or more?), can't it? Of course it wouldn't be fair to demand of any medium to approach the eye's (+brain's) ability, but I'm trying to gather which medium is the best from the current lot.

Are there any tests - slide vs LED/LCD vs paper regarding this subject. Googling didn't help much.

[Ernst Dinkla]

CRT fluorescents do not drop to black when not hit by rays. Whatever masking is used. In a darkroom they will give an excellent black but that is lost fast with any illumination in the room. It certainly is not lith film black.

With CCFL or passive LED backlight, the LCD layer is not sufficiently opaque to block the back light. A compromise has to be found in reducing backlight output which sacrifices the other end of the range. Active LED low resolution imaging as the backlight is a HDR solution:
www.cs.ubc.ca/~heidrich/Papers/Siggraph.04.pdf

OLED displays might bring an easier solution. A combination of active OLED + LCD would probably improve on that. In low ambient light conditions such as a dark room an OLED screen can achieve a higher contrast ratio than an LCD. But not in well lit rooms. I wonder whether OLED output is high enough to keep the other end of the range competitive. OLED lifetime is related to maximum output.


--
Met vriendelijke groet, Ernst

340+ paper white spectral plots:
http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
update april 2012: Harman by Hahnemühle, Innova IFA45 and more

[Sareesh Sudhakaran]

Thanks for the link, Ernst.

What if we have a constantly lit situation in a controlled environment?

[Ernst Dinkla]

If it is for a static image I gave two methods in my first message. The color dye image will not last, the B&W lith film image will be near indestructible. If the color image has to last a two side solvent printed foil will have a better chance. There are sign printers that do this in one print run on translucent banner media/vinyl. The method is much older, silkscreen and offset posters used on light boxes often had the two sides printed, both for saturation and black opacity. Printed on translucent white material it also allows the light box to be switched off during the day and the one side print reflection is then correct on both aspects. It is more complex than that, usually the backside print is not as dense as the front side print and color corrections can be made per print side for the different illuminations, fluorescents versus daylight. I have done that more crude in silkscreen for certain signs with a yellow color on tungsten lit car top lights, a warmer yellow on the outside, a primrose yellow on the inside, minimal shift in hue with and without the sign light on. With my HP Z printers I print two backlit foils and mount them on top of one another. That does not deliver the ultimate in dynamic range. I have no tools to do correct color management for that method either.


--
Met vriendelijke groet, Ernst

340+ paper white spectral plots:
http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
update april 2012: Harman by Hahnemühle, Innova IFA45 and more

[hjulenissen]

CRT fluorescents do not drop to black when not hit by rays. Whatever masking is used. In a darkroom they will give an excellent black but that is lost fast with any illumination in the room. It certainly is not lith film black.

With CCFL or passive LED backlight, the LCD layer is not sufficiently opaque to block the back light. A compromise has to be found in reducing backlight output which sacrifices the other end of the range. Active LED low resolution imaging as the backlight is a HDR solution:
www.cs.ubc.ca/~heidrich/Papers/Siggraph.04.pdf

I have a television set that works like described. 100 or so LEDs illuminate separate zones behind the LCD panel, thus compensating somewhat for the limitations of the panel. The backlighting is also modulated in time. And there are some drawbacks and artifacts connected with this technology.

My objection was to the words "true blacks". In my view, "true black" does not exists any more than "infinite spatial resolution does". What we have is media with some maximal brightness ("white"), and some minimal brightness ("black"). The ratio between those tells us the medium dynamic range, while absolute levels should be compared with the viewing room light sources. Paper, LCD, plasma, OLED, DLP, CRT, etc all have a black level that is different from the ideal black.

I do believe that plasma tvs can give impressive contrast ratios if your viewing room light/reflections are properly controlled.

-h

[Sareesh Sudhakaran]

I do believe that plasma tvs can give impressive contrast ratios if your viewing room light/reflections are properly controlled.

Are there any professional grade plasma monitors available today?