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Technical 1
![]() Shooting The Third Act with the
![]() Panasonic AG AF-100
![]() “I don't think that's even a question anymore,” said indie film-maker Ramin Baharni, answering the “film versus digital" question in the Q & A following the showing of his acclaimed film Goodbye Solo at the River Run Film Festival in April 2009. Bahani's point regarding the advantages of shooting in a digital format for small independent films was, for our production, well made and timely; script development for P.E. Marston's The Third Act was complete and basic decisions would need to be made soon. Canon's 5D MkII still camera had been available for a few months at that point and had been a leading candidate for the shoot until the difficulties of quality sound, fixed 30fps frame rate (corrected a year later with a software update), razor thin depth-of-field, sensor overheating, and other compromises inherent in the nature of the DSLR-as-camcorder became obvious. As Alin Bijan said recently concerning his decision not to shoot on DSLRs: "I wanted a real camera." So did we.
The following year, casting and pre-production for The Third Act had just gotten underway when Panasonic announced their AG AF-100 camera at the April 2010 NAB show (American Cinematographer, June 2010). The AF-100, with the features of a proper cinema camera, immediately captured our interest and we began to take a serious look at it for Marston's project, scheduled to shoot in late 2010 or early 2011.
In addition to high quality sound and other features shared with Panasonic's range of video camcorders, the AF-100, by utilizing the micro 4/3 sensor (m4/3), allows the use of a very wide variety of lenses, a convenience intentionally designed out of DSLRs. With an exceptionally short flange focal distance of 20mm, m4/3 products can accept not only the m4/3 lenses from Panasonic, Olympus, and others, but, with the proper adapter, PL mount (52mm) cinema lenses and SLR lenses such as Nikon's F series (46.5mm) and Canon's FD series (42mm). While our production team didn't have a closet full of Zeiss and Cooke PLs, we did have a large collection of well-proven Canon FDs, which we dubbed “the poor man's Panchros” as most were f2.8 - the same aperture as the venerable Cooke Panchro series. The idea of shooting The Third Act with the AF-100 and FDs became enticing and was very much the sort of production Panasonic had in mind in marketing the camera. While these lenses, with their 1/2 stop aperture increments and lack of follow focus gearing may not be the ideal solution, for the budget-minded film maker their advantages can be considerable. The vernerable Canon FD 50mm f1.4 lens, after all, is considered a benchmark in terms of optical properties and color rendition. Not to mention the fact that these lenses can be owned for 1/20th to 1/50th the cost of cinema lenses, eliminating the need for costly rentals. For a project like The Third Act, which was to be shot a few days a month during breaks in the actors' and crews' other schedules, this was an important consideration.
The AF-100 offers a host of features expected in a purpose-built digital cinema camera, including variable frame rates, HDMI outputs, HD-SDI outputs (simultaneous with HDMI, unlike the RED EPIC), zebras, dynamic range stretching, built in NDs, Vu meters, phantom mic power, timecode, and cine-look pre-sets. For those moving up from smaller format cameras with inherent deep focus, the focus assist feature will be appreciated.
The AF-100's version of the m4/3 sensor is slightly oversized from the standard m4/3 with dimensions of 13mm x 17.8mm. This is smaller than a “full frame 35mm” (nominal 24mm x 36mm ) still camera sensor and slightly smaller in width than an APSc (nominal 16mm x 24mm ) sensor, 1.85 ratio 35mm cine film frame (12mm x 22mm) or the 2:35 ratio "Super 35" film frame (10.6mm x 24.9mm). It has an active (16: 9) area about 2.5 times the 16mm frame (7.5mm x 10.25mm), more than twice the size of the RED ONE or EPIC shooting in 2K 16: 9, and 4.5 times that of a 2/3" sensor. Depth of field is less shallow than with the oversized "full frame" still camera sensors and only a fraction less shallow than with an APSc and 4 perf 35mm but considerably more shallow than 16mm film, the RED ONE/EPIC at 2K, and 2/3" formats.
But the current penchant for super-shallow depth of field is a relatively new fad anyway. For most of its history the goal of cinematography has been increased depth of field. Consider Gregg Toland, one of Old Hollywood's most revered cinematographers, creating his much admired “deep focus” shots for Citizen Kane and Best Years of Our Lives. In order to get that depth of field, given the slow film stocks of the day, Toland was required to pour so many kilowatts onto the sets that the paint blistered. Roger Deakins, ASC, another guy who knows his way around a camera, said recently: “I don't like backgrounds being out of focus.” (American Cinematographer, January 2011). Matthew Labatique, ASC, when shooting handheld subway scenes for Black Swan with an APSc camera, states he had to use ASA 1,600 and light to T8½ to achieve usable depth of field (American Cinematographer, December 2010). And one of the chief complaints of shooting widescreen in anamorphic rather than sperical is anamorphic's 50% reduction in depth of field. Since The Third Act was working in cramped practical locations and automobile interiors, being able to achieve normal depth of focus without a truck full of lights fit perfectly with the size of the production.
If razor-thin focus was not a priority, though, low light performance was, since the script for The Third Act called for a number of car interiors while driving at night (not unlike those of Michael Mann's Public Enemies - American Cinematographer July 2009), street scenes, and the interior of a darkened theater. The AF-100's sensor is MOS - as opposed to the CMOS sensors of most DSLRs and the RED ONE/EPIC. The MOS requirement for two control lines per receptor versus three for CMOS means that the AF-100's receptors are about 40% larger, and therefore perform better in low light situations.
It bears repeating that given the AF-100's 2x crop factor (as compared to the 35mm still frame) the image appears to have the frame of a lens of twice the focal length but will still have the characteristics of the original lens. With a 20mm FD, for example, the frame may have a 40mm field of view but the information will have the less flattened, wide angle 20mm characteristic. With cine lenses the crop factor is 1.19x; in either case we immediately noticed we didn't have to worry about vignetting, softness, fringing, or other edge aberrations as we were working well into the center of the lenses' field of view. Setting the bottom two of the camera's three-position programmable ISO function to 320 and 500 allowed us to create effective quarter-stop aperture increments on the FD lenses with no perceptible change in image quality.
The AF-100 is also a small, lightweight package, an important feature for those cramped car interiors and other locations. With standard battery and accessories it weighs only 3.5 pounds, yet with its cast alloy frame seems quite rugged. The unit boots up in 2 seconds (not 90) and there was no sensor overheating, color drift or other artifacts during continuous maximum resolution test shots to the entire capacity of an 8 GB SDHC card - about 45 minutes. The battery will record continuously for 3 hours and we have had no battery disconnect issues during in-car shots when traveling over rough roads. Another plus is that image modification - color correction, scene files, etc. - done in-camera are output from the camera, not just modified for the monitor as with RED. The image we saw on our 24” field monitor was the image we recorded, greatly reducing post-production surprises. And best of all, the camera has been utterly reliable. Not a single dropped frame, no boot up failures, no overheating, no odd noises on the audio track, no continual software updates to load. We suffered no rolling shutter artifacts and encounterd image skew ("jellocam") only in one extreme circumstance when the frame was whip-panned from total darkness into total light within 2 frames.
Workflow was straightforward. The camera's menu structure was similar to other Panasonic cameras, making for a short teething period. Testing was chiefly centered on achieving smooth skin tones, achieving solid blacks and reducing noise. A great deal, learned but more often otherwise, has been written about the h.264 compression of AVCHD. Very close frame-by-frame and sometimes pixel-by-pixel inspection on a 46” monitor showed material recorded in AVCHD to SDHC cards at 24MB/s to have no identifiable compression artifacts as compared with the same material recorded "uncompressed" to SSDs via the AF-100's HDMI and HD/SDI outputs. In fact, the opposite was true; both the HDMI and HDI "uncompressed" footage showed a number of banding artifacts not present in the AVCHD footage. This is not surprising given that at 24MB/sec the data is only being compressed 3:1. By comparison, RED's "uncompressed" REDCODE36 compresses about 10:1.
The heart of The Third Act is a stage musical written by one of the main characters and the look of the production took its cues from one of the musical's songs, the lyrics of which talk about "living life in black and white." Scenes often swung the light meter from one peg to the other. Even at the extremes we achieved good solid blacks and more depth in the near-burnout whites than expected, allowing us to deliberately de-grade the image as indicated by the scenes.
The early part of the film, in which a bewildered main character is just clinging to reality, was shot in a very raw style with harsh lighting at wide shutter angles and high ISO's to heighten noise, grain, and motion blur. These scenes were further modified in post with a high contrast - low saturation finish. Fantasy sequences, shot in a darkened theater in the beam of a single follow spot, were shot with #2 Smoque and 1/8 Black Pro Mist filters for effect. The final portion of the film, in which the character comes to grips with herself and sets her life on a clear new trajectory, were shot with slightly enhanced saturation and contrast for a "enhanced reality" look. The flexibility of the AF-100 allowed for seamless integration of all the shooting styles (see Gallery/Frame grabs.)
Copyright Neill Fleeman 2011
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