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Spearhead Display
Diamond & Split Diamond Display Characteristics
Aside from making it easy to identify out of Gamut issues when working with RGB Signals one of the big advantages of the
Diamond and Split Diamond display is that it allows the user to see which primaries are contributing to the out of gamut
condition. Errors due to the Green channel will show up in both the Upper and Lower Diamond. Errors in the Red Channel will
show up in the Lower Diamond and errors in the Blue Channel will show up in the Upper Channel.
Arrowhead Display
While the Diamond Display is great for keeping the signal content legal while working in RGB, there is a better then even chance
that our content we worked so hard on will eventually be rendered as, or at the very least later converted to, Composite NTSC
or PAL. The Arrowhead lets us view the converted Y, Pb, Pr information so that we can be sure that it will remain legal even
when converted to a composite format. The result of this is that all the artistic efforts won’t be wasted due to signal clipping if the
signal is used on-air broadcast.
Spearhead Display characteristics
The Spearhead display plots Lightness (monochrome RGB) in the Vertical Axis on the left side of the triangle, Saturation (Red
Dotted Lines) from left to right on the top upper diagonal of the triangle and Value (Blue Dotted Lines) on the lower diagonal of
the triangle.
We describe this in more detail later, but for now just realize monochrome is on the left so a 50% Gray Signal would be a vertical
straight line from 0% to 50%.
Figure 3.
Arrowhead Display.
Figure 4.
Spearhead Displays.
