|
January 30, 2004 |
|
the elusive "film look" for video
- part 1 - Defining Terms
|
Challenging the
Desire for "Film Look"
I've had a lot of online discussions about achieving a "film look" for video
projects.
All too often, amateur
filmmakers don't differentiate between aesthetic and technical points of
image manipulation. In this first of a multi-part series on the "film
look", I'll offer specific technical parameters with which to understand and
perceive the moving image. In subsequent issues, I'll build on this
technical foundation to first, challenge the notion of the "film look", then
offer an aesthetic framework within which to craft your own project's look.
Defining Terms
There are four major areas of aesthetic and
technical concern that distinguish any moving image. It helps to keep them
separate in one’s mind. They are:
o
value – brightness levels,
video’s linear versus film’s curved gamma, exposure, etc.
Value,
or illumination,
o
color – white balance,
sensitivity to particular regions of the spectrum, etc.
Video cameras are generally more sensitive to greens while film responds
slightly better to reds. While there are better DV cameras capable of more
saturation and with larger and better CCD’s, the XL-1s has
a native warmth (similar to film’s sensitivity to
reds) that appeals to filmmakers.
o
spatial – what exists in a
single frame – resolution, detail, filter effects, etc.
60i converted to 30p or 24p results in heavy aliasing (jaggies) on
diagonal lines. This aliasing is not present on 30p acquired imagery. The
XL-1s has a great lens and sufficient 1/3” CCD’s to acquire the level of
detail we need in the frame. I’d like to experiment with the sharpness
settings, as Allen was doing with his GL-1 the other day, to arrive at an
optimum look.
o
temporal – how it moves over
time – 60i, 30p, 24p, etc.
Persistence of vision kicks in around 40 frames per second. While film
plays at 24p, it is actually displayed in the theatre at 48p. Each
frame is displayed twice with the help of a butterfly shutter spinning in
front of the projector lens. 30p retains some of the full-frame
acquisition characteristics of film without hurting the eye with excessive
flicker. I can’t justify the 24p aesthetic when 30p looks just as nice
and doesn’t hurt the eyes.
Glossary
fps – frames per second
60i – 60 interlaced fields per
second – NTSC video records imagery as two sets of interlaced lines.
There are 480 lines from top to bottom of the image. First, the odd lines
are recorded, then the even lines. Two interlaced lines together compose
a full frame.
30p – 30 progressive frames per
second – More recent camcorders can record a whole image (both odd and
even lines) together at the same time rather than as two separate sets of
lines.
24p – 24 progressive frames per
second – essentially what film records at
CCD – cascading cathode device –
the imaging chip used by most camcorders today. In more expensive
cameras, there are actually three chips – one each for red, green, and
blue.
Have fun out there! - Michael Morlan |
