Well-lit video is the essential building block for a
video production, and with both traditional hard
lighting sources and a softbox for more diffused
looks, Lowel Light Manufacturing Inc.’s DV
Creator 44 kit is an excellent starter set.
weatherman to appear to be dematerializing into his map.
But that was long ago. These days, chromakey and
related technologies such as blue and green screen effects
have gotten so exact, they’re the key to Hollywood
blockbusters ranging from the recent batch of Star Wars
prequels to such quasi-comic book films as Sky Captain,
Sin City, and 300.
One reason why these effects have taken off in the
past few years is that compositing via PC has become
Once this model standing in front of Image West’s
10X15-foot green screen is videotaped, the chromakey
applet built into many video editing programs can
quickly and easily replace the green backdrop with
a photograph or a virtual set.
50 September 2008
incredibly sophisticated. And that technology has rapidly
trickled down to the consumer level.
While Hollywood films still have multi-multi-million
dollar budgets, green screen effects have actually saved
them considerable sums by allowing sets to be built in a
computer, not by draftsmen and riggers. Similarly, because
compositing via PC is now inexpensive enough that the
average serious hobbyist can afford it, green screen effects
allow one-man video podcasts to have an extremely slick
look, even if they’re shot in a garage or a basement. They
also simplify lighting. Rather than having to carefully light
a whole room, small, affordable lighting kits, such as those
manufactured by Lowel ( www.lowel.com) — can be used
to aim two or three lights at the talent (the key, fill, and
hair light), and another pair of lights at the green screen
behind said talent.
So, let’s look at some of the elements involved in
producing a successful key.
While there are plenty of keying programs for both
Mac and Windows (and many video editing programs
come with a keying applet built in), Adobe’s Ultra 2
(only for Windows, unfortunately) is significant for three
reasons. The first is that unlike some of the more primitive
keying programs, its software builds a virtual map of the
green screen behind the actor, which means that if the
green screen and actor are properly lit (more on this in
a moment), it can generate an extremely tight key. The
second is that it’s extremely easy to use, particularly if
you have a shot of the green screen without the actor for
the program’s software to do its thing.
The third is that a whole host of virtual sets can be
purchased to place a variety of extremely slick digital
backdrops behind an actor.
What does this mean? It means that a green screen
can be hung in a garage or basement, a handful of lights
placed in front of it, and via a standard DV handycam,
your garage can be transformed into a television news-room, a talk show, a corporate boardroom, a classroom,
and on and on. You can even have helicopter shots
zooming into science fiction backgrounds that Gene
Roddenberry would have given his eye teeth for during
the heyday of Star Trek. Additionally, photographs of
anything from the exterior of your local Best Buy, to the
interior of the Starship Enterprise can be used as a
backdrop. And none of these backdrops have to be lit.
So, all of a sudden, a one-man video podcast starts to look
increasingly slick and inviting.
A portable green screen is fine for temporary set-ups,
but if you have the space, aim for a green screen wide
enough to go to floor to ceiling to take advantage of
these virtual sets. Also, you may want a separate tabletop
lighting system for close-up shots of your project.
Many of the virtual sets that Adobe sells for Ultra 2
have virtual computer monitors and television screens
positioned within them, which allows for additional video
clips to be composited into them. These are great for
having your project on display in the background as you