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September 2015

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Page 39 of 51 38 POST SEPTEMBER 2015 4K HDR AND er at 2.6 compared to today's BT.1886 2.4 television gamma idealized aver- age presentation curve for displays (2.35 Euro). However, the color encod- ing available in the P3 color gamut for high dynamic range is limited based on the current X'Y'Z' 2.6 gamma color encoding equation to 52.37 cd/m2 as peak white (5), and therefore, simply expanding dynamic range in the cur- rent cinema P3 color space in terms of orders of magnitude above the current peak white by raising the light output of the projection system would cause upward clipping in the colors and over representation in brightness. To extend dynamic range with cinema color, it might be better at this time to start with as wide a gamut beyond P3 as possible in the camera capture sys- tem, and then apply the appropriate conversions back into P3 space rela- tive to the accentuation of dynamic range as it may prove to be possible in average or special theatrical settings. It should be pointed out that as movies can be "layered" in their imagery by cinematographers in the placement of lights and filters, and production design elements, so can the colorists accentuate the cinema- tographer's choices to represent dy- namic or subtle tone and saturation differences. Depending on the screen size, the idea is that the end result is to seduce the viewer into areas of the image where better story manipu- lation may occur, especially when the viewer has a larger than normal image in front of them and when the viewer may selectively choose where to look at any given moment. Bear in mind that when subjects in front of a camera are moving through light, and when the color and tone is likely changing from different angles of reflectance relative to the camera lens positions and settings, once the "adjacencies" (scene images that come before and after a given shot) become known, there can be both a logical and passionate need to adjust the image presenta- tion somewhat, such as either for emotional relevance or to increase continuity and image presentation consistency. Traditionally, movie film elements or the cut negative could be print light adjusted in color and for tone as part of this end result evaluative process, to create a more desirable film print and so scenes could more easily be balanced throughout the movie. There were cinematographers who required no such printing adjustments, howev- er, as they made all necessary changes in the actual photography. To accentuate actual and natural light levels and reflectance, versus artificial representations, it can be argued that increasing the dynam- ic range moves the darker and the brighter parts of the image dynam- ically apart, leaving more space for the average reflectance, or mid-tones. Compositional limitations notwith- standing, it would follow that addi- tional attention be given to changes in brightness and color in the dark regions of images such that the gaps into brighter regions are not under- represented in the degree of change. At the same time, it can be argued that the increased brightness can create attention to the resulting in- creases in, and transitions into, higher saturation and higher vibrance. Historically, motion picture and television images of motion pictures had carried at least minimal aspects of high dynamic range using forms of dynamic range compression, such as an S-curve. To the extent new but somewhat slightly different practices for higher dynamic range exist and can become standardized with similar curves, or new methods of open standard code mapping, the results can be better shared across differ- ent technologies and be reasonably adaptable to more of a variety of delivery systems given applicable viewing conditions. In conclusion, substantially accurate, continuous perceptual visual and standards based confi- dence monitoring of choices throughout the production process- es are potentially all the more important for 4K, UHD, and in the use of high dynamic range, to balance the necessary support for both artistic quality, code and compression efficiency and overall technical control. 5 "Design Considerations For Cinema Exhibition Using RGB Laser Illumination," SMPTE Motion Imaging Journal, May/June 2015, p. 32 by Jim Houston and William Beck FILMED UPGRADES WITH PANASONIC 4K CAMERAS NEWPORT BEACH, CA — FilmEd Academy of the Arts (www.cinematicarts. org), which provides production services and filmmaking training to high schools throughout Orange County, recently add- ed 18 Panasonic VariCam 35 4K camera/ recorders to its inventory. FilmEd pro- vides equipment to secondary schools to produce institutional broadcasts and cov- er school events. The organization also develops curricula for advanced media students, mentors film school applicants and provides core movie-making instruc- tion in a series of two-week summer workshops for high school students. Previously, FilmEd students worked with Panasonic AG-HPX500 P2 HD and AG-HVX200 P2 HD camcorders for shoulder-mount and hand-held instruc- tion. The Academy's executive director David Junker went to the NAB conven- tion earlier this year seeking an HVX200 replacement, and was impressed with the new VariCam 35's low-light capabilities. "We were so impressed with the VariCam 35's dual native 800/5000 ISOs, and have worked with Panasonic for so long, that I began to envision the 4K camera as a switch-out for the HPX500s," Junker recalls. By working with AbelCine on a HD by 35 adapt- er, FilmEd found a way to re-use its B4 lenses on a PL mount and conse- quently lower the cost of entry to the VariCam 35s, which were purchased from VMI, Inc. "The VariCam 35 is so ergonomic, requiring only minimal rigging, that we can use it as a documentary camera, but the Super35 image quality and depth of field give us unprecedented cinematic options," he says. FilmEd rolled out the VariCam 35 at its summer workshops, which have just concluded. Beginning students shot in 1920x1080 ProRes HQ while the advanced students shot exclusively in 4K, 12-bit 4:4:4 and 4:2:2 LT. All stu- dents used the VariCam 35 on four test projects, encompassing the production of a PSA, spot feature, music video and short silent film. Editing was done in Adobe Premiere.

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