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Serious Magic
DV Rack Field Guide
Modern cameras have an Automatic Gain Circuit (AGC) that can be enabled for
audio inputs. These circuits try to vary the recording level to match the incoming
signal. As you can imagine, this is a hit or miss process. Most professionals prefer
to monitor and adjust their audio levels manually except in certain circumstances
where this is not possible. DV Rack takes a great deal of the complexity and risk
out of recording audio in manual mode.
Achieving Good Technical and Aesthetic Framing
Overscan, Underscan and the Video Safe Area
Back in the day of the first television sets, TVs had screen sizes that seem paltry by
today's standards. A 12 inch screen was considered a luxury. And to make matters
worse, these expensive little screens actually shrunk as they got older.
As these older sets aged, the visible picture area of the screen shrank because the
electron gun that created the picture, much like you and I, didn’t move as well as
it got older. Try as they might, those poor electrons were unable to get around as
well as they used to and could not fill the entire screen.
Aging TVs sets would start to show a black border around the edges of the picture
where the top of Howdy Doody’s hat and belt buckle used to be. Well you can bet,
customers started to complain. They felt that if they paid the extra dollars for a 12-
inch screen, then the picture better darn well fill the whole 12 inches!
This created a conundrum. The electron gun could be recalibrated to fill the whole
screen, but this solution was time consuming and costly. How could TV manufac-
turers prevent this from happening? The answer was to “crank up” the electron
gun to
Overscan
the picture beyond the borders of the picture tube. This ensured
that as the television aged, the displayable area of the picture tube would remain
full, no black border would appear and children everywhere would never miss a
pixel of Howdy Doody. Once again, all was well in television land. However, it
has frustrated videographers and graphic designers to this day.
When camera operators frame a shot they must always take this television over-
scan condition into consideration by making sure each shot fills the overscan area
while at the same time, not losing any crucial parts of the picture outside of the
Video Safe
area.
The DV Rack Video Safe indicator displays a white border on the Field Monitor
screen. The Video Safe border is centered on the true center of the picture that all
televisions see. To complicate things further, the industry uses the terms Overscan
and Underscan in a counter-intuitive way. When you view the
Underscan
area,
you actually see more of the picture than when you view the overscan area.
NOTE:
Most LCD displays on camcorders try to simulate the Video Safe Area but they
don't accurately show the whole picture which can make it difficult to frame a shot
properly. There may be objects creeping into your shot around the edges of the
screen that you won’t see until you leave the shoot. This is where a Field Monitor with an
Underscan capability like the one in DV Rack becomes important.