INF 385T
Advanced Digital Imaging
Creating Sustainable Collections
April 7, 2008
Housekeeping and announcements
• Margie Compton is coming next week
– Happy hour at Scholz after class
• Academy Film Archive is looking for interns for
the summer!
– Email resume, 3 references, and cover letter to
Kelly Chisholm: kchisholm@oscars.org
The Horse in Motion, by Eadweard Muybridge, as an
animated sequence
Muybridge’s original still images were taken at the Palo Alto racetrack on
June 19, 1878. Muybridge reportedly won a bet with a friend who held
that at no point were all four of a running horse’s feet off the ground.
Film into video
• Film: A sequence of similar images that, when
projected or viewed by means of an
intermittent shutter mechanism, creates the
illusion of realistic motion
• Video: Also a sequence of still images that
create the illusion of motion when viewed in
succession…but televisions and computer
monitors don’t have a shutter!
Interlaced video
Alternating fields are combined (interlaced) to compose
frames of video. NTSC standard is 29.97 progressive
frames/second (30 interlaced frames). PAL/SECAM video
runs 24.93 progressive/25 interlaced frames/second.
What issues does this create?
• Frame rate conversions (there is no one
standard frame rate for film!)
• Visual differences when watching telecined
footage on progressive (us. computer) vs.
interlaced (us. television) monitor
• And then, of course, there’s high-def…
Moving right along to aspect ratios…
• Since 1917, there have been at least 6 frequently
used aspect ratios (image proportions) for film
– Not always easy to identify full-frame, unmasked films
– Full silent aperture and Academy ratio very similar,
but not identical – an issue in projection/viewing
• Widescreen and anamorphic standards pose the
biggest problems for film-to-video transfers and
hi-def conversions (up or down)
• These are especially problematic when multiple
formats are mixed in the same project (ex:
documentaries w/archive footage)
Training your eyes to assess film and
film transfers
• Identifying film when it’s being projected
– Look for grain quality in medium-value areas
– Dirt, hair, flecks in light areas, esp. at head and tail of reels
– Dark areas that are even or transition smoothly (saturated
exposures may have “pooled” darks or “blown out”
highlights)
– Changeover cues (the “cigarette burn”) in the corner
– Light beam from projector in booth will not be as steady as
during digital projection (may come from different
window, depending on the booth); edges of projected
image may show some motion too
– In bad cases, you may see obvious or midframe splices
• Identifying and evaluating digital projection
– Rock-steady projected image
– Absence of dirt or scratches
– Texture of the image is different—grainless and
smooth
– Color range may be somewhat different—whites
may be creamier or more opaque-looking, blacks
flatter, less inky than in a film projection
• Assessing transferred film
– Look for dirt, specks, or hairs (esp. in large, light
areas or around edges)
• Keep your transfer equipment very clean!
– Watch large dark areas and, especially,
backgrounds for digital artifacts: blocking,
chunking, pixelation, and flattening
– Compare relatively still scenes with scenes that
have a lot of action or motion in them, both small
and large movements