Category: Picture Quality

DCP TIFFs

Intention: Provide materials which can help a technical or non-technical people – cinema managers and other employees, in particular – subjectively judge changes in picture and sound quality without the use of meters.

If the test equipment isn’t scheduled at the auditorium for another 6 months, is there a way to tell if the the contrast and color display is degrading? These TIFF slides are experiments to answer this question, and supply tools if it is possible. Suggestions are welcome. All these TIFF plates are 4096 x 2160, 2020 color space with 16 bits of depthiness, unless otherwise mentioned. Sound files from the DCPs will get their own page, but don’t go looking for it now…

If you have some ideas for changes, to fix mistakes or add nuance, let us know…likely we can change the master for the better and post another version. Creative Commons License This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.  
If you create something and would like it hosted on this site, please let us know. Read what the link says on the Creative Commons site. Generally, you can use these in your works, change as required. But please, 1) give attribution when you use them in either commercial or non-commercial work, 2) provide a link to the original material and, 3) send a note to let us know what you changed.

White to Black dials Brighter and 709
White Squares with a Radial Gradient and Scale

White2Black Dials This TIFF started as an experiment in seeing smoothness from 100 to 0 all over the screen. Really, it was striking as a color print so the logical extreme was black to white everywhere. There are 3 versions in the set, each pushing the center point of the gradient just a little to one side or the other from center. Confuse them at your own risk. And for each one there is a version with a dial. When you make your DCP, use one after the other so the talent can make a judgement without the dials, then mark down the place where any problem exists. The dials on the TIFF files look much better than what is compressed here. Please give them a try, and let us know. As Always, 16 bit, 2020 and the Passcode is QA_b4_QC    


Primary and Secondary color dials
White and Colored Squares with a Radial Gradient and Scale

Primary and Secondary Dials These radial dials are an experiment to see if broken or funky gradients can be observed or perhaps even be seen gradually going odd over time. As Always, 16 bit, 2020 and the Passcode is QA_b4_QC  


4 Colors, 10 Boxes TIFFs Once more, an attempt to see what can be seen in HDR / EXR projector systems, then to find which ones can be used to notice any degradation in the system. These would be the normal SMPTE required RP 431-2 set of blocks going across, but they also have a smooth gradient going across the bottom. …and, they don’t start at 100%. There are 3 sets, one which starts at 10% luminance and goes to 1%, another from 1% to 0.1, and – you guessed it, the 3rd set goes from 0.1% to 0.01%. Thus, with 65,535 as 16 bits, the range of these goes from 6,553 to 7 units of color. More specifics at the download page… For some reason, this Rec 709 PNG at 6554 – 655 with outline and it doesn’t seem to show on the computer screen. My guess is that with the surround of white the eyes are shut down too much to see them.

Sample of the Green colors with outline

Anyway, this is the 4th of this series, attempting to find an objective measurement technique to quantify changes. The link above gives you a set of TIFFs. And at this link, there is a DCP. Let me know what works please.  


Vertical meter of each primary color and black at 2 different luminance.

Vertical Meters TIFFs The question for these slides is “Can you objectively and consistently judge where the color ends and only black exists”? Will several people see the same ending point.  The underlying question is can the meters be used as tools to objectively judge contrast? If there is a lot of dust on the port window or in the room, will there be a difference? On each slide there are 16 bars of color, 8 starting at 5% luminance in the center and going to 0% at top and bottom, and 8 going from 2.5% and going to 0%. One the left is a set of 4 of each for RGB and White on the left, and the right side is a complete set, through in a different order. The idea was to see if a bright color like green made it too hard to judge the blue if they were adjacent. Indeed, these are experimental. In addition to 5/2.5, there is also a slide with 2.5% and 1% meters, and for those with an extraordinary system, 1% to o.1%. Is 5% a usable meter for each color or is 2.5% more useful in a xenon powered room? The theory is that one can look at the meter and make a substantially objective judgment, record it on one of the checklists, and use the test again a week or month later to note if there are changes. Wow! This PNG only begins to show a usable scale…download the TIFF file.  


GreenDial with tics marks in 709

Dials for Contrast: 6%, 4.5%, 3%, 1.5% RGB and Greys, with and without tic marks. This idea is similar to the vertical meters above, but as dials with the gradient from 6% to 0% (as well as 4.5% and 3% and 1.5% to 0) on a dial, and in several colors. There is a version with a set of tic marks to note where the last point of seeable color is…and a version without. Why? Because it may be that one needs to spot the position of where the color disappears, without the influence of the dial markings, then get the markings later. In the DCP the dials show for 5 seconds then the dials with the tic marks and numbers show together for 5 seconds. Experiment and report please. RGB and Greys. 2020. 4K and 16 bits of depth for each color. All to see if we can get an objective tool that an interested and intelligent person can use. A little trouble making a file that shows on the screen at such low luminance. Try the TIFFs.  


Numbers above grey steps x 40
Grey Steps x 40

Grey Steps with Dirty Numbers The classic row of grey boxes is defined in SMPTE RP 431-2: D-Cinema Quality – Reference Projector and Environment document. One row in the center of the screen. Problem is, it isn’t a very good test of a modern digital cinema projector, is it? This TIFF file has every square of grey from 2.5% to 100%, plus a ramp from 2.5% to 0%. And above that is a set of numbers, that give the luminance value of the square…but it gives it 3 times, and the digits are in three different values. The bottom value is 1% lower, and the middle is 0.1% lower and the top number…hopefully able to be seen in that fancy million to one system, is 0.01% different. The trick is to see if these numbers show up on a screen. Have fun and do share your thoughts. As always, 2020 color space and 16 bits of depthiness. The DCP is at: GreyStepScales These are the numbers that are laid on top of the squares…can your system produce differences for some or most of them?  


2117 5 Percent Solution These Dots are made for testing. These two TIFF files are one for Scope and one for Flat with the dots placed on a 5%W line as specified in 296M. Have fun and do share your thoughts. As always, 2020 color space and 16 bits of depthiness. More info is on the actual download site.


2117 Test Plates 1a These Dots are made for testing. First to check that they are usable, and 2nd for putting on the front screen and testing for luminance without glare. There are two sized dots, 10% and 20% of height. They sit on a rectangle that is 15% in from the edges of the Flat or Scope screen. There are 4 type of TIFF files for each Flat and Scope, two 10% and two 20% but one each for 1.90 Full Frame and one each for 2.39 Scope (top and bottom cropped off for a 1716 pixel height) and a 1.85 Flat (with the edges cut off for a 3996 width.) As always, 2020 color space and 16 bits of depthiness.  


LensTesting for DCinema!

Primary and Secondary Trumpets Each of these components will be made available in a kit, but for right now, here they are in one chart.  


Variation 1 on Mach Band Effect Testing

Mach Band Effect Testing Plates There is a whole series to download here. These were developed to learn whether the black of the masking curtains and the typical vignette of the picture cause the illusion of luminance shift.  


Black lines against primary and secondary backgrounds 2020 16 bit

Horizontal and Vertical Lines – Black, against backgrounds, 2020, 4K Black lines at every other position on the grid…and a variety of different primary and secondary backgrounds.  


colored lines, horizontal and vertical

Horizontal and Vertical Lines – Colored Lines, 2020, 4K What is the difference to a projector or a LED wall between drawn black lines and backgrounds of colors…which actually fill in the alternate lines, right? …and drawing the colors as the lines and letting the editing program put in the background…or no background at all. You too can find out with these plates.  


Color Plates, 2020, 4K Primary and secondary color plates – Don’t need pictures of those here, do you? Just get them at the download site.  


Colors on a black background that also checks the sides in a colorful manner.

2 Percent Hmmm – What shall we call this? It is derived from the CST chart that marks off 2% rectangles to begin with, and a bunch of circles drawn at the proper 10% points…then it got botched up with moving the color wheels to align with the corner to corner lines which actually serve no purpose…ok, toss in some focus squares …that’ll distract them. (This png is 709…get the real thing in 2020 and tell us how to make it better please.  


Black and white Siemens Stars with several 2% rectangles.

2 Percent, Black and White Hmmm – What shall we call this? It was inspired by/is derived from, the CST chart that marks off 2% rectangles to begin with, and a bunch of circles drawn at the proper 10% points…then it got botched up with moving the color wheels to align with the corner to corner lines which actually serve no purpose…ok, toss in some focus squares …that’ll distract them. (This png is 709…get the real thing in 2020 and tell us how to make it better please.  


CJ’s Favorite Distraction Several variations with several colors going from full saturation to dark or white …and grey level tests too. A distraction because I keep refining it. Now with MTF marks – hope they work…haven’t tested them yet.

Black background with sharp lines and green cones
Green Cones with MTF lines and other designs

trumpets on a scope screen

Trumpets 8 TIFFs of Trumpets. The ability to watch as lines get closer together. There are many variations…there are numbers in there somewhere. Experiment and report please. RGB and Black. 2020. 4K and 16 bits of depth for each color. All to see if we can get a subjective objective.  


A number of testing ideas on one chart

Circles and Stars Circles and Stars and a few other things to stare at. And some fun while making the primaries turn into secondaries. Ya gotta love bluey yellow, no? The alternative TIFF uses outlines of the Siemens Stars for the center position, just to see what detail they hold. No idea if a 4K system can hold 48 spokes…let us know what you find please. RGB and Black. 2020. 4K and 16 bits of depth for each color.  


Freq Wavelengths – This is just a pretty lesson in 16bit 2020 (which if you haven’t noticed, is the same as all the others above), an attempt to see the entire color space in a different way. Wavelengths in one direction, frequencies in the other. Whiteness on top and blackness on the bottom. Use as you will and have fun.

In the future I am going to try to corral the different typical gamuts on this. The usual horseshoe bends upward and only shows the white point in the center and the fake Line of Purples on the bottom. How to do that. And wouldn’t a horseshoe that shows the black point be fun?

VisibleSpectrum 2020 wFreq 25pct

 


JND Radials

This is another way to put all the colors of the spectrum into view at the same time.

22 Slides. 2 Pairs, Scope and Flat. All in the 2020 space, excepting a few for publishing and trying on in a Display PC device like the iPad over there.

Most all with a twin that Each pair has a square grid overlay to make a game of noticing how subtly the colors change.  

One set is white to black and the other is black to white.

Eventually there will be another set in 3840 x 2160, but for now these are all in Cinema 4K, 4096 x 2160.

Radial Flat 2020 Black emanating to all colors emanating to white 


MacBeth – Variations on 2020 Experiments – The MacBeth Chart is great for what it does and the software is very responsive as well. Built initially for the printing and then photographers needs, it proved a good way to establish a camera and locations light variance situation and give Post Production a good start.

Of course, these days of super saturated 2020 colors, or even P3, goes beyond what the MacBeth Chart delivers. This is an experiment for how it would look, old and new, on the big screen.

 

Variations on MacBeth

More as they happen


A crafted circle in a triangle in a rectangle with 3 primary colors all around

Coming….Colors, Stripes, Dials, MoreMTF –

 

 

10b) What Does It Mean: Scope and Flat? Part 2

Hi, and welcome.

The information on this page has been transferred and updated at the Training Course page: What Does It Mean: Scope and Flat? Part 2.

Scope or Flat can best be shown with some examples of how it goes wrong. These drawings were made because exactly this problem happened in a local screening room for a movie screening to a room full of experts.

The intention isn’t to make fun of anyone, of course. These things happen by mistake more often than by negligence or bad repair. The screening company representative said that there was a run-through previous to the showing and everything was fine. Since she left the room after her welcome statement, we don’t know if what we saw is what she saw previously. It is possible that she didn’t know what to look or listen for, which is exactly why we need to document this. This Lesson will help you to understand this situation, recognize it right away as you do  your auditorium inspections…and fix it right away. Continue reading “10b) What Does It Mean: Scope and Flat? Part 2”

1) What Does It Mean: DCP

Hi, and welcome.

The information on this page has been transferred, with updates, to the Training Course page: What Does It Mean: DCP

We recommend that you use the newer link.

Let’s start with something that we will hear about all the time.

A DCP is a Digital Cinema Package. You will never hear, “Did we get the Digital Cinema Package?”. No one will ever say, “Will you play my independent movie please? I can send you the Digital Cinema Package.” No. Instead, they will say, “We got the DCPs.” Or, “I’ll send you the DCP on a hard disk.”

Yes, it is digital, and it is cinema. Digital simply means that is capable of being used by a computer. In case you are not certain, the projector, and the media player for the projector, and sound system are basically just specialized computers. Cinema, of course, means that it has something to do with motion pictures, usually in an auditorium. (The word “cinema” hasn’t had a long life, only about 100 years. The originators of modern motion pictures, the Lumiere brothers, chose the word from the Greek word from Ancient Greek word kínēma – which means “movement”.)

The reason the DCP is called a package is that it holds all the frames of the movie, plus all the music, dialog, sound effects, all the subtitles and the files for the blind/partially sighted, deaf and hard of hearing, and the security keys. In addition, the package has some extra files that tell the computers which of those files to play, and when. Continue reading “1) What Does It Mean: DCP”

10) What Does It Mean: Scope and Flat?

Hey! Hi. This page is was duplicated at the Training Courses site, with new edits, at:What Does It Mean: Scope and Flat?

Please use this new site, since it will be the most up to date and it will come with new features. Thanks!

:

The first question: Why Do We Care?

Every Answer begins the same way: There are many things that can go wrong with the presentation of the moving picture.

In this case, we are working with the shape of the picture. Movies evolved from almost square to very wide.

This topic is a little tricky. Even if the shape is wrong – too narrow or too short – at least the image is on the screen. In some cases, the images may look OK if you just glance at the image. But there are things to look for.

Will the audience care? Many will. They will think that the screen looks too small, or the image looks too small. (Nobody ever complains about too big!) They may complain that the people on screen are too thin, or too fat.

Buzzwords: “Scope” “Flat” “Format” “Constant Height” “Constant Width” “Aspect Ratio” “Two-Three-Five” “One-Eight-Five” (written 2.39 or 1.85 and 2.39:1 or 1.85:1). We will show the definition of these terms with examples. Don’t look them up now – they have too many meanings and most explanations are more complicated than we need to be.

The Complication: There are 2 correct forms for an image on the screen. Even in the same facility, some auditoriums may be one type, and other auditoriums may be the other type!

Masking and Curtains in a Cinema Auditorium

Potential Points of Failure: Screen. Curtains. Motors for Curtains. Cord for Curtains. Masking. Motors for masking. Chains for masking. Automation Electronics. Projector. Automation setting on Playlist. Instructions that tell which setting to put into the playlist!


Don’t let this get too complicated. We are only talking about the size of the rectangle of the movie on the screen.

Movies are created in 2 different shapes. The measurements for both of them is just about 2 times as large side to side (the width) compared to the dimension from top to bottom (the height). For example, the following picture shows this concept of a rectangle that is 2 times wide and 1 times high.

A pretend cinema screen two times wide and one times high

A simple way to write this is ‘2 to 1’ or ‘2:1’, which means 2 units in one direction compared to 1 unit in another direction.)

The important things to remember is:

There are two formats

One format is slightly smaller than 2 times wide and 1 times tall – that format is called Flat.

One format is slightly wider than 2 times wide and 1 times tall – that format is called Scope.

Here is a picture of those 2 formats placed with our 2 to 1 picture.

Two to One, with Flat and Scope

The choice for this happens very early in the movie making process – probably during the first hours of conversation between the producer and director, or sometimes the director and the cinematographer. Will we shoot this movie wide or do we shoot this movie tall?

Of course, they don’t use those terms. Art and Science are never that simple – there are always special words, or words with special meanings. They choose between “Scope” or “Flat”.

There is no rule that says a movie should be one way or the other. Sometimes a director will only work in one form, then suprise you by making a movie in another. Or, sometimes people will say that all action movies are in Scope. But a little research will show that isn’t always true.

Anyway, after the director’s decision, every scene of that movie will be shot through a lens that is in that form – what is called a format. And of course, the last lens of the movie process – the lens that is attached to your projector – will make the movie appear in that format on your screen.

Here be dragons!Maybe you remember those old maps with the ship at the edge near the sign that says: Warning – Here Be Dragons~! Well…Warning — Here Be Maths~! …and, yes, we promised to keep math to a minimum. But there will be drawings too, with arrows and bright colors. So, be brave. Continue reading “10) What Does It Mean: Scope and Flat?”

1a) Where to Judge The Auditorium

Hi, and welcome.

The information on this page has been transferred and updated at the Training Course page: Where to Judge The Auditorium.

There is no perfect answer for “Where should I be to judge the screen and sound system?”

Actually, we don’t need to be in a “perfect” place. We just need a consistent place – measure from the same place every time. Still…the question is: Where?

How High Is This Screen? when it falls on you?One group of experts will say that you should judge from so many “Screen Heights” away.

A screen height is just like it sounds, and a little difficult to evaluate exactly. In the movie theater, if a screen is 64 feet wide, then the height is 27 feet high. Maybe. Because there are two different standards for screens.
Continue reading “1a) Where to Judge The Auditorium”

Beta Test – New, Online, Managers WalkThrough Form

We are preparing the launch of an exciting new service. Out with the old paper form of the Managers WalkThrough Report Form – In with the Online Forms. Give it a try.

Use the link on the line above, or click on the “Routines” pulldown in the Menu above.  Select Managers WalkThrough Report Form on your phone or tablet or portable computer. Get settled in the auditorium that you want to check  the sound and picture. When ready, have someone start up one of the Cinema Test Tools DCPs …and click away on the online form.

If everything is cool, all stays nice and simple. But if any of the answers requires that you pass information to the tech (for example), the form magically opens up, giving you a place to tell everyone what you saw or heard.

Like the DCPs and lessons, the new Online Form Series is free. We hope you will use it for every theater every week…or more if you want. The Safety and Security Form is just about ready and the Monday CleanUp will also be released soon. Read further to learn about emailing the form and other Q&A. Continue reading “Beta Test – New, Online, Managers WalkThrough Form”

7) Measuring Light

Hey! Hi. This page is was duplicated at the Training Courses site, with new edits, at: Measuring Light

Please use this new site, since it will be the most up to date and it will come with new features. Thanks!

Imagine that you have joined a  non-technical employee Quality Assurance Project. You might have many goals: I want to learn a bit more about the technology of movies, or, I want to be part of a well trained team that keeps customers happy… and you might have many different purposes for those goals: If I can help create happy customers, they come back more often…or, if I have good control of the basic skills, I can use them to get even more important skills, becoming more valueable to my team and company. To accomplish these goals and achieve these purposes, there are many things that need to be done.

Of course, your goals and purposes must align with the quality policies set by the CEO of the company (Cheif Executive Officer). The CEO might say that your small village theater can only get so much money for seat and carpet replacement and do the best with what we have, but we are not a premium movie palace. Or, the CEO might say, spare no expense, this is the Flagship Theater for the entire chain and it has to be the best. Or, something in between.

Usually there is a way to be true to your aspirations and stay within the boundries set by the boss. No matter what, the boss would never want us to compromise safety, or show a bad image on the screen, or let the sound get full of distortion. They probably want to make sure that each patron is satisfied with what the facility and what the staff have to offer, even if it can’t be the perfect place. So this includes wanting an educated staff that is able to communicate intelligently with patron and tech staff.

And that is what we are going to do, a little at a time – learn to communicate about the performance of the facility with the patrons, a little at a time. In this section we are going to learn about measuring light levels with simple equipment …your iPhone, right?

So, if at first you don’t have the organizational support to download DCPs onto a USB drive, then get the DCPs into the Media Player/Projector system right now – you can still download some audio and light measuring tools, and experiment with them until you can use them easily in a dark room.   Continue reading “7) Measuring Light”

8) What’s It Mean? Contrast…

Hey! Hi. This page has been duplicated and updated at the Training Courses site: What’s It Mean? Contrast…

Please use this new site, since it will be the most up to date and it will come with new features. Thanks!

As usual, the first question for every “What Does It Mean” topic is: Why Do We Care?

Every Answer begins the same: there are many things that can go wrong with the presentation of the moving picture. In this case, we are working with how much dark and how much bright there is on the screen.

This one is a very tricky. The image is onscreen. In most cases, the images may look OK if you just glance at the image, or if you don’t know what to look for.

Will the audience care? Maybe not. They don’t know what “Correct” is.  They will think that the picture lacks “Pop”, or some other quality. But if you don’t know that the black suit is really supposed to have fine light blue lines in it, then the black suit might look OK.

Buzzwords: “Black Levels”, “Crushed Black Level”, “No Greys”, “Gamma Problem”, “Brightness”.

We will show the definition of these terms with examples of how they apply to our situation as someone who is checking the quality of the picture. Don’t look them up now since they have many meanings and most are more complicated than we need.

Complication: Almost all cinema projectors have a problem creating perfect blacks. But there is a range of deep blacks and deep grays that they should create without problem.

And white too! Perfect white is never shown – it would ruin your eye’s ability to notice differences between things when the picture is too bright.

Which is the problem with Contrast…too bright, you can’t see details in the darks. Too dark – muddy – you can’t see the detail in the bright.

There needs to be a good range – when you look in the dark, in the shadows, there should be richness in the dark reds and and dark blues and and dark greens and and greys. And when there is is bright scene, there should be good pastel colors too.

Another problem is – We don’t always know what the artist wanted – a lot of movies are ‘moody’ and ‘dark’. But even dark movies shouldn’t be mushy.

Potential Points of Failure: Bad setup on the Projector. Wrong Lens. Port Window, if very dirty. Old screen. Dirty screen.


Look at these three versions of the same winter scene at Yosemite Falls in California.

In the first one, you can see the amazing falls against the crisp rocks, and the golden hour sun is beautifully lighting up the mountaintop.

In the 2nd one you can almost taste the frost from the frozen lake. The air is so crisp and clear that you can see several layers through the trunks of the trees. If you hadn’t already seen the gold in the mountains, the 2nd picture would be OK.

The 3rd is in between…not as on fire, not as clear through the tree trunks…dark in fact. The falls don’t stand out as sharply against the rocks.

By now you may have guessed, the 3rd one is the one that the artist created. The difference in the three is entirely the level of Contrast.

Low Contrast


So. What is Contrast?

Simply, in the cinema, there is a level of white and a level of black. Outside, on a sunny day, the level of bright can be 30,000 or perhaps up to 120,000 at the brightest day at the brightest time in the brightest place…and reflections on cars…they can be 10’s of thousands of bright too! And, the level of black? Wow, a dark night sky in a forest when you can’t see the hand in front of your face – a single candle will seem very bright indeed. Let’s call a candle at arms length 1. Move the candle away and it becomes .1 and .01 and .001. In theory, our eyes can still see that candle on a perfectly dark and clear night when it is many miles (or kilometers) away.

Move the candle close to you, or put several candles in your hand…or a light that has the power of several hundred candles …well, at some point you get too much light in your eyes and, in protection, they shut. And inside the eyes, in protection, there is a protection mechanism as well.

But let’s not get off the point: Contrast is the difference between the highest level of bright and the lowest level of dark. If black is 1 and white is 2,000, then we say the contrast is 2000 to 1. It is written like this – 2000:1. When it is written like that, it is called the Contrast Ratio.

Why do you need to know that?

You want to have a good feeling about your ability to notice good and bad contrast. And, most importantly, how to tell the technician what you see when there is a problem.

We give a little more detail about these things in Part 2, with more examples.


But first, take a break. The exercise for this lesson is to look in shadows while you are living life.

Notice: there are important details to see in the shadows. Look under tables. Look into the dark and notice how colors shift down to black. You might have to purposely shade your eyes from a bright light.

And: Notice how there are things to see even in light that is almost too bright to look at. The colors will be softer in bright light, even for the same shoe or car or face that was a deep rich color when you saw it in the dark.


When you have experience and a good feeling for these ideas of Contras, click into Contrast – Part 2

Photo by Rodrigo Soares on Unsplash