Sherlock Holmes and the Dark, Sinister World of Black Levels

Friday, February 26, 2010

Posted February 25, 2010 by Jennifer Davis & Erik Guslawski

I finally got a chance to watch the critically-acclaimed Sherlock Holmes, from Warner Brothers starring Robert Downey Jr. and Jude Law, in the theater this weekend.  

I love a “who done it” and am a self-proclaimed technology geek, so I found the story and the characters really engaging.  Without spoiling it for everyone, it is a classic tale of science winning over fear.  In line with the novels, the tiniest details and astute observations lead to revolutionary outcomes.

Sitting there in the dark theater, I couldn’t help but think how great the movie will look on a Runco projector in your home, when the Blu-Ray is released later this year. The cinematography is useful in teaching about one of the single most important qualities in any display: black levels.

For those of you who have seen the movie or the trailer, it is very dark. There are shadowed alleyways, sewer tunnels, midnight meetings, and of course, a main character who has dark hair and likes to dress in the Morag.

So, to shed more light on the importance of black levels, I consulted one of our gurus who works with dealers in the field every day to get extraordinary results in home cinema, Erik Guslawski, Runco Field Technical Product Specialist. “The deeper the black are, the more contrast our eye perceives and this actually makes the picture look sharper to us,” he explains. “When you don’t have deep blacks and all you have is a sort of gray/ dark gray, the whole image will appear hazy and cloudy rather than clear. You will likely see each and every detail in the shadows but overall the image will not ‘pop’ very much. It will look flat and lifeless. When you have only ‘jet black’, there are no details in the shadows and the black level is really ‘crushed’. This is far from ideal.”

To evaluate a display for black levels, we recommend finding an image or scene that includes dark details. For instance, find an image of someone with black hair (something that will be easy to do in Sherlock Holmes). Do you see each strand of hair or just a solid black mass? Clothing, like pin stripes on dark suits, or the detail reflection from a black piano shown in a Grammy broadcast, is also a great way to see black levels. The ideal display will portray inky dark black levels (a key element for getting good contrast) and maintain the very fine “just above” black details (which provide realism and in the case of Sherlock Holmes, the clues to solving the mystery).

According to Erik, there are plenty of test patterns used to check and set black level. Below is his explanation of how to use such a test pattern:

Commonly known as PLUGE pattern it will usually contain a solid 0 IRE background and at least two black bars or stripes. If it’s a proper PLUGE pattern (and if the source device outputs the signal properly), one of these stripes will actually be BELOW black. It would appear darker than the black background. Technically one would never see anything below black in actual video content, but it’s very useful for setting black level. The other stripes would be just above 0IRE, say about 2.5IRE and/or perhaps 5IRE. The way you use this pattern is to set the brightness control down far enough to the point where the BELOW black stripe disappears into the 0IRE background but you can still see the other bars that are just above black. The theory is that by making the “blacker than black” bar disappear into the background, which is 0, and still able to see the information just above that, you have the deepest black levels the display can produce while still being able to see everything above that. Think of the 2.5 and 5IRE stripes as the fine pin stripes or threads on someone’s clothing. If you set the brightness control too far down you will lose those details. The “blacker than black” bar is there simply as a reference point. If you are setting the brightness control and you can still see that -5IRE bar, you need to keep adjusting. The whole idea is to get the deepest black levels you can while still seeing everything just above “black.” I always recommend that after you set levels using test patterns to go to some good video content (I have my favorite clip of Katharine McPhee that is good for this purpose) and evaluate the image to make sure you are seeing those details. Often times I find myself tweaking the brightness control UP one or two ticks from what I got when using test patterns alone.

PLUGE stands for Picture Line-Up Generation Equipment. Pluge patterns are usually generated by specialised video calibration equipment such as a synch pulse generator.

There are many types of pluge patterns but they all contain a variety of black, white and/or gray shaded areas.


  1. The first vertical bar (on the left) is black and can't be seen against the background
  2. The second vertical bar is only just visible as a dark gray.
  3. The third vertical bar is a lighter gray and clearly visible.
  4. The white box is a comfortable level of true white.
  5. There is no colour in the pluge display at all.


Now, the next step to getting a well-tuned display for your environment is adjusting white levels for contrast (and these two interact with each other so they should be done in concert), but we’ll save that for another post (or authorized Runco dealers are always invited to our Runco Academy courses where Erik and the team will teach them all they need to know about perfecting a Runco product in their clients’ homes. See the partner portal for a schedule and details.)

In all cases, adjustments to a display should be made in the ambient lighting conditions in the client will be watching the display. “Ambient room lighting and the colors of the furnishings and finishes in the room will affect how your eye picks up those black stripes,” Erik contends. In a pitch black room with no stray light hitting the screen those bars are very easy to see, but that may not affect real average viewing conditions or content. “This is why I like to recommend using patterns that have some bright elements in it as well, so that you can see how the reflected light off the screen will bounce off the walls and ceiling and adjust for that. In addition to the below black and slightly above black bars you will use to set black level, a good pattern will also have gray steps that will vary from about 20-100 IRE. This helps to add some of that inevitable light splash back into the room which gives you a more real world idea of what you will see,” he concludes.

Until Sherlock Holmes is released for home viewing, we recommend the following movies and scenes that have excellent dark content for testing and perfecting black levels on your Runco video product:


  1. The Dark Knight: Chapter 20
  2. Chris Botti in Boston: “I’ve Got You Under My Skin featuring Katherine McPhee” Chapter 8 0:48:00 to 0:52:20
  3. Casino Royale: Chapter 2 00:10:20 to 00:11:17
  4. The Taking of Pelham 123 – which shows a real installation of Planar’s rear-projection command and control room products in NYC subway scenes
  5. I Am Legend: Chapter 8 00:29:26 to 00:31:51




Jennifer Davis - Jennifer is all about technology innovation and is a customer advocate, business executive, mom, and loves her job as Runco’s VP of marketing.

Erik Guslawski - Erik has over a decade of experience in the custom electronics industry as an installer, system designer, sales rep and is now a product specialist for Runco International.

News & Events


Planar, Leyard Expand Award-Winning Clarity Matrix Video Wall Line-up with Extreme Narrow Bezel

21-Jul-2016 - Industry’s smallest seam LCD video wall display features a tiled bezel width of just 1.7mm for virtually seamless installations and Full HD stereo 3D model. Today a..... more ▶

Next-Generation Planar UltraRes Series 4K Displays Deliver the Ultimate Ultra HD Experience

07-Oct-2015 - Best-in-class 75”, 84” and 98” LCD displays offer enhancements in multi-source viewing and 4K video support Planar Systems unveiled the next-generation of it..... more ▶

Experience Runco

Request a Demo at a Dealer Near You

Photo gallery

Awards & Recognition

Electronic House Product of the Year Award

Electronic House Product of the Year Award

Runco’s 3Dimension™ D-73d Series

More Awards ▶