AJA kona3 Installation And Operation Manual page 20

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A Note About YPbPr—Component Video, or YPbPr, has been given several names over
time. YUV, Y/R-Y/B-Y, and YCbCr, are just some examples. Although these various formats
have some differences in levels, they are all basically the same. KONA 3 uses the modern
YPbPr terminology exclusively. KONA 3 supports three different types of YPbPr: SMPTE/
EBU N10, Betacam (NTSC), and Betacam (NTSC Japan). These three formats differ in level
only and are configured in the KONA 3 Control Panel.
A Note About RGB—Although RGB is used less in today's video systems, KONA 3 supports
it for A/V Monitor output. However, because KONA 3's (and SMPTE SDI's) native format is
YPbPr, AJA recommends the use of YPbPr whenever possible for analog monitoring.
Although component video monitors often have RGB inputs, it's better to use YPbPr
when the monitor supports it. The YPbPr format provides "headroom" for "superwhite"
and "superblack"—and these video levels will be clipped when transcoding to RGB. Also,
the RGB/YPbPr transcoding involves a level translation that results in mathematical
round-off error. RGB can be configured in the KONA 3 Control Panel.
Reference Video
A single BNC connector is standard on the KONA 3 cable (self terminating). Two BNC
connectors are standard on the breakout box (these provide loop through: if ref is not looped
out, a 75 ohm terminator should be used for the loop out connector). Reference allows you to
synchronize KONA 3 outputs to your house analog reference video signal (or black burst). If
you have a sync generator or central piece of video equipment to use for synchronizing other
video equipment in your studio, then connect its analog composite output to the KONA 3
reference input. When KONA 3 outputs video it uses this reference signal to lock to. When
connecting a reference video source, the locking signal should be the same format in Hz
(1080i29.97, 625i25, etc.) as the Primary format selected in the KONA 3 Control Panel. It is
possible in some circumstances to use an alternate format video signal as long as the basic
frame rate is compatible (for example, using a 525i29.97 genlock signal to lock a system
running 1080i29.97)—if the Hz coincide.