Media Technology

Broadcasting Color Correction Guideline For C-TV Productions Using Apple`s Final Cut Pro

Media Technology

Broadcasting Color Correction Guideline For C-TV Productions Using Apple`s Final Cut Pro

Abstract

Broadcasting Color Correction Guideline For C-TV Productions Using Apple`s Final Cut Pro

Campus TV, short “C-TV” is the name of 30 minutes of TV program, which students of the St. Pölten University of Applied Sciences Media Technology produce every month. All work in C-TVs productions is done by students. Every year, the most experienced students leave the C-TV team, because they have successfully finished the education at the St. Pölten University of Applied Sciences Media Technology. As a result a lot of important knowledge leaves with these students. Every year a new team of students starts to work at C-TV and all necessary things for producing 30 minutes of TV have to be learned again. Next to editing, or sound mixing which students learn during the education at the St. Pölten University of Applied Sciences Media Technology the important part of color correction often stays behind. Unlike editing, shooting, sound mixing or recording, color correcting is not a subject at the St. Pölten University of Applied Sciences Media Technology. As a result most of C-TVs productions since C-TV has started its productions, two years ago, did not have any color correction. Facing these facts, this work aims to be a color correction guide for Apples Final Cut Pro. The software Final Cut Pro is used for editing in C-TVs workflow. Final Cut also offers an inbuilt color correction software which is powerful enough to fulfill all needs to make C-TVs productions suitable for broadcast. This work explains how to use Final Cuts color correction tools from a beginner level on. All necessary tools, buttons, and sliders, for color correction in Final Cut are explained. The author uses practical examples, illustrated with pictures how to use Final Cuts color correction tools. Based on examples the work shows common mistakes, during shooting and gives ideas to solve these with color correction. Using examples of different movies the work illustrates how to create different color looks. The work completes with a brief overview of color science explaining color spaces and technical background knowledge on video formats.

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Media  Technology  

Broadcasting  Color Correction Guideline For C-TV Productions Using Apple s Final Cut Pro  

List  Of Content  

Introduction   

1.  Basics of Color Correction page.  7

1.2  How To Calibrate The Video Preview Monitor page.  7

2.Basic  Color Correction Tools page.  8

3.  The Video Scopes page.  10

3.1  Waveform Monitor page.  10

3.2  The Vector Scope page.  12

3.3  The Histogram page.  14

3.4  The RGB Parade page.  15

4.  Range Check page.  16

5.  The Broadcast Safe Filter page.  19

5.1  Using The Broadcast Safe Filter page.  19

5.2  The Different Options Of The Broadcast Safe Filter page.  20

6.  Frame Viewer page.  21

7.  Correcting Bad Camera Adjustments page.  23

8.  Creating Looks page.  27

8.1  Old Movie Look page.  27

8.2  Day for night page.  28

8.3  Schindler s List / The Sin City Look page.  29

8.4  Home Movie look page.  30

8.5  Sitcom look page.  31

8.6  Matrix Green Effect page.  32

9.  Introduction In The Science of Color page.  33

9.1  Light page.  33

10.  How The Eye Works page.  35

10.1  Rods , Cones page.  36

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Media  Technology  

Broadcasting  Color Correction Guideline For C-TV Productions Using Apple s Final Cut Pro  

List  Of Content  

10.2  Cone Resolution page.  37

11.  Additive And Subtractive Color page.  38

12.  Color Spaces page.  39

12.1  Stimulus Specific Color Space page.  39

12.2  Devise Dependent Color Space page.  40

12.3  Video Color Spaces page.  40

12.4  Y, R-Y, B-Y page.  41

12.5  YUV page.  41

12.6  YCbCr page.  41

12.7  YPbPr page.  42

12.8  YIQ page.  42

13.  Bit Depth page.  42

14.  Subsampling page.  43

15.  Color Correction With Other Built In Software Than Final Cut page.  45

15.1  Adobe Premiere Pro and Adobe After Effects page.  45

15.2  Avid page.  45

Bibliography  page.  46

Notes  And Queries page.  47

List  Of Figures page.  49

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Media Technology

Broadcasting Color Correction Guideline For C-TV Productions Using Apple`s Final Cut Pro

Introduction

This work is a manual, as I would have needed it in the last year, in order to make a color correction suitable for broadcasting, without much previous knowledge. Based on practical examples, my work illustrates how color correction for broadcast is done, whereby this study is limited to the Program Final Cut, since this is used in the c-tv workflow. The following study is useful for those who use Final Cut to correct the color, as it is not necessary to extend the workflow to another program and maybe learn how to use a color correction software. My work will explain how to prepare videos for broadcasting using Final Cut. In the end f this work a introduction in to the science of color can be found.

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Media Technology

Broadcasting Color Correction Guideline For C-TV Productions Using Apple`s Final Cut Pro

1. Basics of Color Correction

In general, there are two types of color correction: primary and secondary color correction. The first is used for making scenes look the same. Secondary color correction is used for stylizing an image. For any form of color correction you must use a video preview monitor. Only a calibrated video preview monitor allows you to see the image in its true colors. It is not possible to do a color correction using the canvas window on your computer monitor as it will display the colors completely different compared to the original colors. The computer monitor always displays different gamma, saturation, color depth, and many more. The three things you need for color correction are, a calibrated video preview monitor, the video scopes of the color correction software you use, and, last but not least your eyes. Before you start make sure, your preview video monitor shows the right colors. In case it does not, calibrate it.

1.2 How To Calibrate The Video Preview Monitor

1. Turn on the video preview monitor, at least 20 minutes before you start calibrating.

2. Dim the lights in the room and take care of sun, lamp, and light

^{Figure 1 JVC NTSC/PAL Preview} reflections.

Monitor

3. Select “ bars “ in the monitor`s menu.

4. Set the contrast to its centre point of 50%. 5. Turn down the chroma and brightness to 0% until the shades of color bars are just black / white.

6. Turn up the brightness until you can see the black color bar separated from the blue color bar left to it. Figure 2 JVC HD Preview

Monitor

7. Turn up the contrast until you see a difference between white and yellow. 8. Change into the “blue-only mode“

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Media Technology

Broadcasting Color Correction Guideline For C-TV Productions Using Apple`s Final Cut Pro

9. Turn the chroma to a level where the yellow-green-red-black color bars show the same amount of black and the cyan-magenta-blue color bars show the

same intensive (75%) of blue/gray. The white color bar must be brighter.

Now you have successfully calibrated the video preview monitor. You ^{Figure 3 Color Bars} can begin the color correction.

2. Basic Color Correction Tools

You might have never used Final Cut`s color correction filters. They are easy to understand once you understood the principal of how you have to work with filters in Final Cut. To add a filter to a movie clip in the timeline you need to double click on the clip in the time line so the clip appears in the viewer window.

To activate the filter “Go to -> Effects -> Video Filters-> Color Correction -> Color Corrector”. In the viewer window you can edit the filter now.

Final Cut offers two basic color correction filters. The “Color Corrector” filter and the “Color Corrector 3-way” filter. The “Color Corrector” is a simple tool and good to start with. The “Color Corrector 3-way” is more sophisticated and gives you more control about the colors. You might have noticed that at the top of the viewers window a new option has popped up. Here you can edit the “Color Corrector” filter.

Both “Color Corrector” filters allow you to edit their values in a

numeric or a visual view. Although the preset on Final Cuts color correction filters is always in the numeric view, it is

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Media Technology

Broadcasting Color Correction Guideline For C-TV Productions Using Apple`s Final Cut Pro

advisable to use the visual view as it is more self-explaining. To get to the visual view you need to click on the box called “Visual”.

The “Color Corrector” filter properties show two colored

wheels and four slide controls at the bottom of the window. A rule of thumb of color correction says if, there is too much of one color and you need to reduce that particular color, you add the opposite color from the color wheel. For example, when you have been filming outside in bright sunlight your picture might be too blue. To reduce the blue, you need to add more red into the picture.

click on the little white dot at the centre of the balance wheel and drag it into the orange / red area of the balance wheel. The closer you drag the dot to the borders of the wheel, the more saturation you add. When you click on the tiny white dots at the bottom of the right corners of the balance and hue wheels, you can reset all changes you made. By sliding the small triangle around the hue wheel the color of the whole picture will transform according to your preferences. The slide controls below the color wheels give you control over whites, mids, blacks and the saturation.

For example: by sliding the “Whites” controller to the right you can make the picture brighter. By sliding the “Mids” controller to the right you can bring up the luminance for the mid-tones. The saturation slide control changes the saturation of all colors. When you slide the saturation to the left side the whole picture becomes black and white. The auto command buttons are to the right side of the slide controls. The “auto white and black control” checks if your image is too white and if so, reduces the whites. The “Auto Contrast” checks if your image is too white and too black. If so, both are reduced. You will find the same options and some more in the “Color Corrector 3-way” filter again.

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Media Technology

Broadcasting Color Correction Guideline For C-TV Productions Using Apple`s Final Cut Pro

3. The Video Scopes

When you change into Final Cuts color workspace some new functions appear on the screen. I am going to explain the basic functions starting with the “Video Scopes”. To get to Final Cuts color workspace do the following “Go to -

> window -> Arrange -> Color Correction”. Now the “Video Scope” tab containing four boxes has opened.

Looking from the top left to right you see the “Vector Scope“, the “Histogram”, the “Waveform Monitor” and the “RGB Parade”.

3.1 The Waveform Monitor

On the top of the “Video Scope” window choose -> “Waveform Monitor”. To show you how the “Waveform Monitor” works I have prepared a gradient from white to black. The “Waveform Monitor“ shows the luminance and the saturation of the picture. The luminance is shown from the top to

the bottom the saturation from left to right. The bottom line is zero percent black and the top line is one hundred percent white. This is the legal broadcast range. You can see that there is some space beyond

100% white. Page 10

Media Technology

Broadcasting Color Correction Guideline For C-TV Productions Using Apple`s Final Cut Pro

This is the area your DV camera records white, because a DV camera records super white.

Super white is not broadcast legal ^*1 , and the legal because it 109% broadcast range is represented in the “Waveform Monitor” as 100%. The luminance of the gradient from white to black on the left is

represented on the “Waveform

Monitor” on the upper left where it is 100% white to the bottom right where it is 0% black. To see the saturation, right click in Final Cut and “choose -> Saturation”. You can crop in to particular colors using the crop tool. In this example you can see that the white levels are beyond 100% which means they are not in the broadcast legal range. In order to legalize the clip, you need to lower those levels. There are different ways to do this. The easiest and fastest way is to use the auto level function of the “Color Corrector 3-way” filter. Additional information on using the filter’s options can be found in the chapter „Correcting Bad Camera Adjustments“. Each one of the pixels in the Waveform Monitor represents a pixel in the image clip. It is possible to “read” the image clip through the Waveform Monitor.

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