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Post-Installation Cinema Test Tools; USL LSS-100 and DTT Digital eXperience Guardian

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The unit plugs into the cinema facility’s IP network so these readings can be taken by anyone with access through the firewall.

The unit is small and unobtrusive, with only the power and ethernet cables going through the wall, connecting the system into the booth and then to the IP network.

This is how the setup page looks, and following that is a shot of the unit itself and a version of the report it creates.

USL LSS-100 Setup Sheet

 

USL LSS-100 Network A/V Monitoring Device

 

USL LSS-100 Report Page

Another network device is the DXG – Digital eXperiance Guardian from Digital Test Tools, LLC. This new company is filled with industry veterans and this is their first product in this collaboration.

The DXG setup is more complex since both its microphone section and its colorimeter remote suspend from the ceiling. In one sense it is easier, since it uses Power Over Ethernet, which puts power, control and data on one ethernet cable.

The design uses 5 microphones to discern levels at many frequencies, as well as phase and the direction of THD problems. Pulsed sounds at various frequencies avoids the buildup problems that pink noise creates. With all this, if a new rattle or hum occurs, a technician can be sent by the NOC to look for something in a particular direction that reacts to a particular frequency, decreasing the time to find whatever got loose or was inserted into or taken from the audio system.

Like the USL system, the DXG’s value comes from giving the user “changes from a baseline” measurements. Both systems would be used after a picture and audio room tuning to establish that baseline. Since the DXG captures much more data (levels and THD at different frequecies from individual speakers, and phase information from pairs of speakers at multiple frequencies, for example) the output is put into an xml file and an SQL database so that reports can be generated. These standard tools allow the client to easily integrate the data and reports into their monitoring systems.

There is also a parameters list which the customer sets up to monitor “warning” and “critical” points that can trigger notification through Web 2.0 interfaces. And, critically, the system uses ‘percentage of variation from the baseline’ since it is easier to keep track of trends this way instead of using baseline numbers that might vary from room to room. Knowing that the data point has gone beyond a 5% threshold, for example, is easier to notice than figuring whether the new x,y matrix numbers are within MacAdam’s Just Noticable Difference oval.

In addition to the “variation from the baseline” concept the DXG colorimeter also includes a pull-down in the auditorium set-up page to mark date and serial number changes of bulbs, both for 2D==>3D changes and for EOL changes. Plus, instead of one 2 degree spot – the SMPTE/ISO spec for calibration – the DXG colorimeter measures a broad section of the screen.

The system includes audio and picture DCPs that run through the projection system. The test system and projection system run asynchronously, meaning that there is no connection or feedback to or from the system under test. A playlist is created with automation instructions to shut down the lights, put the masking in the proper position, put the sound processor at the proper level, make a warning annoucement in the room, then play the DCPs in the proper sequence. Since audio contamination from adjoining rooms would throw off the audio tests, care must be taken when setting up the daily or weekly process.

The DigitalTestTools literature states that there is plenty of space for growth with the DXG, with options for forensic marking tests and IP network tests coming in the near future, as well as an option to test the signals from the various equipment that broadcasts data and sound to personal closed caption and enhanced listening systems for the deaf, blind, hard of hearing and partially sighted patrons.

Following are some screen shots from the Digital eXperiance Guardian. There is a features movie at Digital eXperiance Guardian Movie.

Now that over 80% of North American screens have made the digital conversion with the EU and UK not far behind, it is great to see that the industry has matured to deal with this last lingering problem of screens drifting out of spec. Consumers complain about it, exhibitors have paid enormous sums to get equipment that can be impeccably tuned. Now there are two methods to montor the actual room.

Finally, it should be pointed out and noticed that your author/editor, Charles ‘C J’ Flynn of dcinematools.com is also Charles ‘C J’ Flynn, a founding partner of digitaltesttools.com – he is also a long term admirer of USL and the excellent equipment that they produce. So while this article is somewhat an infomercial, it is written as a scientist and disseminator of valuable information…and presuming that it is just a launching point for further research. C J Flynn has also been a long time advocate of Post-Installation Cinema Compliance, writing and presenting at IBC on the topic as far back as 2006 (after retiring from the labors of setting up cinema servers and training their users since before Star Wars II.

Digital eXperience Guardian – the DXG Multiroom Network Setup

 

Digital eXperience Guardian – The DXG Rear Panel showing Power Over Ethernet Interface

DXG Report – One Speaker – With Errors

Integrator News

Post-Installation Cinema Test Tools; USL LSS-100 and DTT Digital eXperience Guardian

Leave a comment

The unit plugs into the cinema facility’s IP network so these readings can be taken by anyone with access through the firewall.

The unit is small and unobtrusive, with only the power and ethernet cables going through the wall, connecting the system into the booth and then to the IP network.

This is how the setup page looks, and following that is a shot of the unit itself and a version of the report it creates.

USL LSS-100 Setup Sheet

 

USL LSS-100 Network A/V Monitoring Device

 

USL LSS-100 Report Page

Another network device is the DXG – Digital eXperiance Guardian from Digital Test Tools, LLC. This new company is filled with industry veterans and this is their first product in this collaboration.

The DXG setup is more complex since both its microphone section and its colorimeter remote suspend from the ceiling. In one sense it is easier, since it uses Power Over Ethernet, which puts power, control and data on one ethernet cable.

The design uses 5 microphones to discern levels at many frequencies, as well as phase and the direction of THD problems. Pulsed sounds at various frequencies avoids the buildup problems that pink noise creates. With all this, if a new rattle or hum occurs, a technician can be sent by the NOC to look for something in a particular direction that reacts to a particular frequency, decreasing the time to find whatever got loose or was inserted into or taken from the audio system.

Like the USL system, the DXG’s value comes from giving the user “changes from a baseline” measurements. Both systems would be used after a picture and audio room tuning to establish that baseline. Since the DXG captures much more data (levels and THD at different frequecies from individual speakers, and phase information from pairs of speakers at multiple frequencies, for example) the output is put into an xml file and an SQL database so that reports can be generated. These standard tools allow the client to easily integrate the data and reports into their monitoring systems.

There is also a parameters list which the customer sets up to monitor “warning” and “critical” points that can trigger notification through Web 2.0 interfaces. And, critically, the system uses ‘percentage of variation from the baseline’ since it is easier to keep track of trends this way instead of using baseline numbers that might vary from room to room. Knowing that the data point has gone beyond a 5% threshold, for example, is easier to notice than figuring whether the new x,y matrix numbers are within MacAdam’s Just Noticable Difference oval.

In addition to the “variation from the baseline” concept the DXG colorimeter also includes a pull-down in the auditorium set-up page to mark date and serial number changes of bulbs, both for 2D==>3D changes and for EOL changes. Plus, instead of one 2 degree spot – the SMPTE/ISO spec for calibration – the DXG colorimeter measures a broad section of the screen.

The system includes audio and picture DCPs that run through the projection system. The test system and projection system run asynchronously, meaning that there is no connection or feedback to or from the system under test. A playlist is created with automation instructions to shut down the lights, put the masking in the proper position, put the sound processor at the proper level, make a warning annoucement in the room, then play the DCPs in the proper sequence. Since audio contamination from adjoining rooms would throw off the audio tests, care must be taken when setting up the daily or weekly process.

The DigitalTestTools literature states that there is plenty of space for growth with the DXG, with options for forensic marking tests and IP network tests coming in the near future, as well as an option to test the signals from the various equipment that broadcasts data and sound to personal closed caption and enhanced listening systems for the deaf, blind, hard of hearing and partially sighted patrons.

Following are some screen shots from the Digital eXperiance Guardian. There is a features movie at Digital eXperiance Guardian Movie.

Now that over 80% of North American screens have made the digital conversion with the EU and UK not far behind, it is great to see that the industry has matured to deal with this last lingering problem of screens drifting out of spec. Consumers complain about it, exhibitors have paid enormous sums to get equipment that can be impeccably tuned. Now there are two methods to montor the actual room.

Finally, it should be pointed out and noticed that your author/editor, Charles ‘C J’ Flynn of dcinematools.com is also Charles ‘C J’ Flynn, a founding partner of digitaltesttools.com – he is also a long term admirer of USL and the excellent equipment that they produce. So while this article is somewhat an infomercial, it is written as a scientist and disseminator of valuable information…and presuming that it is just a launching point for further research. C J Flynn has also been a long time advocate of Post-Installation Cinema Compliance, writing and presenting at IBC on the topic as far back as 2006 (after retiring from the labors of setting up cinema servers and training their users since before Star Wars II.

Digital eXperience Guardian – the DXG Multiroom Network Setup

 

Digital eXperience Guardian – The DXG Rear Panel showing Power Over Ethernet Interface

DXG Report – One Speaker – With Errors

Consultants

23 degrees…half the light. 3D What?

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Sillver Screen Light Failure Point3D Luminance Issues—Photopic, barely. Mesopic, often. Scotopic? Who knows…? 

We don’t mean to be picking on the good people at Stewart Film Screens by making an example of their Silver Screen light rolloff curve. They just happen to grace us with the most usable graphic description of what is happening to our light. Looking at Harkness Screens Data Sheet for Spectral 240 3D Screens is not better and may be worse. 

We know the problems of getting light to the eyes for any of the available 3D systems. The initial filter eats up to 50% of the light from the projector, plus the manner of each eye getting turned off 50% of the time, and the darkness of the glasses all steal a lot of light. If the projectors could produce enough light to overcome all these transmission problems…which they generally can’t…it would just mean more burnt expensive bulbs and higher electricity costs. 

But even if the exhibitor cranks it as best as possible, and tweaks the room to get the best RGB balance at the best seats of the house, if the auditorium is using a ‘silver’ screen to maintain the polarity of the RealD or MasterImage system, the patron who is 23 degrees off the center-axis will have half the light available. Put another way, as you can see from the full picture at the Stewart site, 3 seats away from center is a totally different picture…as is the 4th and 5th, etc., as the situation just gets worse. 

If the cinema had achieved 5 foot Lamberts (17 candela/m2) behind the glasses (most don’t get 3ftL – 10c/m2), then 3 seats off center will be 2.5ftL (8.5c/m2). At this point, bright reds have all turned to brick red or darker, and blues are becoming relatively dominant – it isn’t that there are fewer yellows or greens in the picture – it is that the eye becomes better able to discern the blue in the mix. (Another way to describe what is known as the Purkinje shift is that an object that appears greenish-yellow in brighter light will appear to be greenish blue as the intensity of the light descends lower than below 10 candelas/m2.) Combine that with stray light from a few EXIT signs, which not only mess with the contrast but puts non-symetrical data into the normally “practically-” symmetrical 3D mix, plus some reflections in the back of the eyeglasses and the patrons should not wonder why they don’t universally have an enjoyable experience. 

We won’t beat this into a pulp since most real-life scenarios just get worse.

What will make it better?

Consumer education to begin, which is the real excuse for this article. Patrons must know what to insist upon. 

Projectors can’t generate enough light to get 3D up to the 14ftL (48 candelas/m2) that 2D movies are shown at. But the new Series II projectors can do ‘more’ and industry tests show that ‘more’ is better, especially if the original was ‘mastered’ to be shown at ‘more’. James Cameron was prepared to ship theaters a ‘print’ of Avatar that was mastered at hotter levels for cinemas who asked for it…up to 10 ftL! Patrons must insist that if they are paying more for the experience, they should get better…perhaps 10ftL is not going to be the standard this year, but 7 or 8? Grass roots effort anyone? The studios set the intention in the DCI spec at 14, so one would think that they will come to the plate with ‘more’ if asked. [DCI Specification 1.2; page 48…and tell them that you want an order of Uniformity and some of that ±4 Delta E while they’re at it.] 

The future also holds at least two potential ways that will give a better picture. Brian Claypool at Christie points out that one of the features of the Series II projector is “more native support for faster frame rates.” For example, many people in the creative community believe that higher frame rates will do more for image quality than having more pixel resolution. Again, Brian Claypool, “Do you remember how rich every frame was in Avatar, that your eye just kept wanting to look around? Well, imagine having 2 times as many frames for your eyes to follow… it will feel like looking out a window on another reality”.

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The other, also long-term, change is replacing bulbs with lasers in the projectors. Good news on that front was announced by one player, Laser Light Engines. We deconstructed their newest announcement and some of their potential at: Laser Light Engines gets IMAX funding—Putting Light on the Subject. 

Some mark this as digital cinema’s 11th year, but it wasn’t until 6 years ago that 2K was delivered, an example of the evolution of this industry. 

Links: Luminance Conversion Table

Scotopic Issues with 3D, and Silver Screens

Knoting Laser Light

Consultants

The State of Digital Cinema – April 2010 – Part Zero

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What they came up with is called the tri-stimulus system since the primary idea is that there are nerve endings in the eye which act as receptors, some of which primarily deal with green light, some with red and some with blue. These color receptors are called the cones (which don’t work at all in low light), while the receptors that can deal with low levels of light are called the rods.

Now, for the first of our amazing set of numbers, there are as many as 125 million receptors in the eye, of which only 6 or 7 million deal with color. When (predominantly) only one type of these receptors gets triggered, it will send a signal to the brain and the brain will designate the appropriate color. If two or more of these receptors are triggered, then the brain will do the work of combining them much the same way that a painter mixes water colors. (We’ll pretend it is that simple.)

OK; so how do you create a representation of all that color and detail on the TV or movie screen?

Let’s start with film. We think of it as one piece of plastic, but in reality it is several layers that each have a different dye of different sensitivity on it. Each dye reacts in a different and predictable manner when exposed to light through the camera lens. In the lab, each layer goes through a different chemical process to ‘develop’ a representation of what it captured when exposed by the camera system. There are a lot of steps in between, but eventually the film is exposed to light again, this time pushing light in the opposite manner, through the film and then through the lens. That light gets colored by the film and shows up on the screen.

One of the qualities of film is that the chemical and gel nature makes the range of colors in the image appear to be seamless. And not just ‘appears’ with the definition of “gives the impression of.” In fact, there is a great deal of resolution in modern film.

Then TV came along. We see a smooth piece of glass, but if we could touch the other side of a 1995 era TV set we would feel a dust that reacts to a strong beam of electricity. If we look real close we will see that there are actually different color dots, again green, red, and blue. Engineers figured out how to control that electric beam with magnets, which could trigger the different dots of color to make them light up separately or together to combine into a range of colors, and eventually combine those colors into pictures.
That was great, except people wanted better. Technology evolved to give them that. Instead of lighting up magic dust with a strong beam of electricity, a couple methods were discovered that allowed small colored capsules of gas to be lit up and even small pieces of colored plastic to light up. These segments and pieces were able to be packed tightly against each other so that they could make the pictures. Instead of only hundreds of lines being lit up by the electron gun in the old TV set, now over a thousand lines can be lit up, at higher speeds, using a lot less electricity.

Then a couple engineers figured out make and control a very tiny mirror to reflect light, then quickly move to not reflect light. That mirror is less than 25% of the size of a typical human hair.

Hundreds of these mirrors can be placed next to each other on a chip less than 2 centimeters square. Each mirror is able to precisely move on or off at a rate of 144 times a second, which is 6 times the speed that a motion picture film is exposed to light for a picture.

This chip is called a DLP, a Digital Light Projector, because a computer can tell each mirror when to turn one and off, so that when a strong light is reflected on an individual or set of mirrors, it will create part of a picture. If you put a computer in charge of 3 chips, one for green, one for red and one for blue, the reflected light can be focused through a lens and a very detailed picture will appear on the screen. There is a different but similar technology that Sony has refined for their professional cinema technology which uses crystals that change their state (status).

Now for the 2nd in our amazing set of numbers. There are 1,080 rows made up of 2,048 individual mirrors each for over 2 million 2 hundred thousand mirrors per chip. If you were to multiply that times 3 chips worth of mirrors, you get the same “about 6 or 7 million” mirrors as there are cones in each eye.

Without going into details (to keep this simple), we keep getting closer to being able to duplicate the range and intensity of colors that you see in the sky. This is one of the artists goals, in the same way as the engineers want to make a lighter, flatter, environmentally better television and movie playing system. It isn’t perfect, but picture quality has reached the point that incremental changes will be more subtle than substantive, or better only in larger rooms or specialist applications.

For example, a movie that uses the 2K standard will typically be in the 300 gigabyte size. A movie made in 4K, which technically has 4 times the resolution, will typically be less than 15% larger. This movie will be stored on a computer with many redundant drives, with redundant power supplies and graphics cards that are expressly made to be secure with special “digital cinema only” projectors.

Hopefully you have a feeling for the basic technology. It is not just being pushed onto people because it is the newest thing. The TV and movie businesses are going digital for a number of good reasons. To begin with, it wasn’t really possible to advance quality of the older technology without increasing the cost by a significant amount…and even then it would be incredibly cumbersome and remain an environmental nightmare. There are also advantages of flexibility that the new technology could do that the old couldn’t…or couldn’t at a reasonable price or at the quality of the new.

The technology of presenting a 3D image is one of those flexibility points. 3D was certainly one of the thrills of Avatar. The director worked for a decade learning how to handle the artistic and the technical sides of the art. He developed with closely aligned partners many different pieces of equipment and manners of using existing equipment to do things that haven’t been done before. And finally he spent hours on details that other budgets and people would only spend minutes. In the end James Cameron developed a technique and technology set that won’t be seen as normal for a long time from now…and an outstanding movie.

Could Avatar have been made on film? Well, almost no major motion picture has been made exclusively on film for a long time. They all use a technique named CGI (for the character generated imagery), which covers a grand set of techniques. But if you tried to generate the characters in Avatar exclusively on a computer with CGI, they never would have come out as detailed and inspiring as they did. Likewise, if he tried to create the characters with masks and other techniques with live action, you wouldn’t get the texture and feeling that the actors gave to their parts.

Could Avatar have been displayed with film, in 2D. Yes, it could have and it was.

3D is dealt with in more detail in Part II of this series, but here are some basics:

To begin, 3D is a misnomer. True 3 dimension presumes the ability to walk around a subject and see a full surround view, like the hologram of Princess Leah.

In real life a person who is partly hidden in one view, will be even more hidden or perhaps exposed from another view. On the screen of today’s 3D movie, when a character appears to  b partly hidden by a wall as seen by a person on the left side of the theater, they will also appear the same amount of hidden by someone on the right side of the theater.

In fact, what we see with out eyes and what we see in the new theaters is correctly termed “stereoscopic”. We are taught some of this in school, how to make two lines join somewhere out in space (parallax) and draw all the boxes on those lines to make them appear to recede in the distance…even though they are on one piece of paper. There are several more clues in addition to parallax that we use to discern whether something is closer or farther, and whether something is just a drawing on a sheet of paper or a full rounded person or sharp-edged box…even in a 2D picture.

And we have been doing this for years. We know that Bogie and Bergman are in front of the plane that apparently sits in the distance…our eyes/brain/mind makes up a story for us, 3 dimensions and probably more, even though it is a black and white set of pictures shown at 24 frames per second on a flat screen.

Digital 3D is an imperfect feature as of now. It has improved enough that companies are investing a lot of money to make and show the movies. The technology will be improved as the artists learn the technology and what the audiences appreciate.

Although we are in a phase that seems like “All 3D, All The Time”, 3D isn’t the most important part of the digital cinema transition. At first blush the most important consideration is the savings from all the parts of movie distribution, including lower print costs and transportation costs. But actually, because prints no longer cost over a thousand euros, and because it will be simple to distribute a digital file, lesser known artists will have the opportunity to get their work in front of more people, and more people will find it easier to enjoy entertainment from other cultures and other parts of the world.

This Series now includes:
The State of Digital Cinema – April 2010 – Part 0
The State of Digital Cinema – April 2010 – Part I
The State of Digital Cinema – April 2010 – Part II
Ebert FUDs 3D and Digital Cinema

Consultants

Question 0: What is the exact definition of DCinema

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[The question is being answered by David Reisner of D-Cinema Consulting. David is a board member of several organizations such as the ASC and ISDCF, co-author of several books on many fields of the cinema process and specializes in design and implementation of digital cinema infrastructure projects.]

For nearly 100 years, motion pictures have been delivered to theaters on 35mm film and have been shown with film projectors.

Digital Cinema, officially called D-Cinema in the technical community, delivers movies to theaters as digital files – most often on harddisk, sometimes via satellite, probably in future also by network/internet.  The movies are then shown using digital cinema servers (special purpose computer systems) and theater-grade digital projectors.  D-Cinema also includes/requires a number of digital and physical security mechanisms, to keep content (movies) safe.  The key documents are the DCI “Specification” (actually a requirements document) and a number of SMPTE standards.

D-Cinema requires support for 2048 x 1080 or 4096 x 2160 images and 14 foot-lambert brightness (similar to film standard brightness, although theaters sometimes use lower light levels for cost).  Movies are distributed in 12-bit X’Y’Z’ color – much more color detail than HDTV’s Rec. 709.  X’Y’Z’ can represent all the colors that a human can see, but the real limitation is the projector (and, to be fair, the camera and post-production process).  All D-Cinema projectors show at least a minimum color gamut which is a significantly wider range of color than Rec. 709 – similar to the range supported by film.

For some markets or purposes (e.g. pre-show, advertising, maybe small markets), some people use things informally called electronic cinema, e-cinema.  There is no formal standard for e-cinema although there is some informal agreement in certain areas.  E-cinema will have lower resolution, narrower color, less brightness, and little or no security.

Major studio content will only be distributed to D-Cinema systems that meet the SMPTE and DCI specifications and requirements, and have passed the DCI Compliance Test.

David Reisner
D-Cinema Consulting
image quality, color, workflow, hybrid imaging
[email protected]
www.d-cinema.us