5

Chapter 23 Using Color Bars for Video Calibration 331
IV
This involves using two pieces of external video hardware:
 Processing amplifier (or proc amp): A proc amp provides hardware control of luma, or
video gain (brightness), chroma gain (saturation), hue, pedestal (also referred to as
setup, which is the black level), and Y/C delay. By connecting a proc amp between
your analog VTR and your video interface, you can precisely control the incoming
Y´C
B
C
R
video signal.
Note: Some VTRs have a built-in proc amp.
 Hardware waveform monitor or vectorscope: Having a dedicated hardware waveform
monitor or vectorscope enables you to measure the actual analog Y´C
B
C
R
output
from your video interface.
The following is a typical setup for calibrating the capture and output of analog
broadcast video.
Calibrating Video Monitors With Color Bars
Videographers don’t rely on the viewfinder of a camcorder to adjust the image being
recorded. Viewfinders and camcorder LCD displays are often too small and have color
fidelity that’s too inaccurate to ensure proper focus, brightness, and color adjustments.
Instead, a properly calibrated video monitor can be set up on location to monitor the
video during shooting.
Similarly, editors and broadcast designers shouldn’t rely on an uncalibrated monitor
when making crucial adjustments to the color and brightness of their movie footage.
Instead, it’s important to use a calibrated broadcast monitor to ensure that any
adjustments made to exposure and color quality are accurate. For more information
about color bars, see “Using Color Bars” on page 321.
Standard definition
monitor
Waveform monitor/
vectorscope
Analog or digital VTR
Proc amp
Computer
PCI card
Input A
Input B