ISDCF held its 3-D luminance demonstration this month. This was the first demonstration in years that harkens back to the days of the ETC Digital Cinema Lab. Jerry Pierce and Kevin Wines deserve enormous credit for planning, preparing and executing the demonstration brilliantly and with zero budget. The community support through donation of equipment, time, and skills was impressive.
The demonstration was framed as an effort to determine an appropriate light level for mastering 3-D content. Several clips from popular 3-D movies were shown. Versions of each clip were specially prepared by color timing them for 4.5 ft-L, 6 ft-L, 10 ft-L, and 14 ft-L. Each version of each clip was then projected at the light level for which it was intended, and then again at light levels for which it was not intended. I.e, the 4.5 ft-L color-timed clip was projected at 4.5 ft-L, and then again at higher light levels. Then the 6 ft-L clip was shown in a similar manner. This pattern was repeated for nearly every clip.
If one was looking for imperfections, then detailed scrutiny was bound to reveal them. My goal was to observe what would be acceptable to the audience, knowing that imperfections were bound to exist. I discussed my observations with others afterwards. The results: 4.5 ft-L looked better than anyone was expecting it to. And 3-D content mastered at higher luminance levels was reasonable when viewed at 4.5 ft-L. 6 ft-L looked good. 10 ft-L looked better, but the change in quality wasn’t as great as the change in quality from 4.5 to 6. Many people found the difference between 6, 10, and 14 ft-L to be minimal in terms of impact. Some were most comfortable with the 3-D effect at 14 ft-L.
Most exhibition systems today are capable of 4.5 ft-L due to practical and economic limitations. My take away from this is that 3-D content could be mastered at a higher luminance level without upsetting the apple cart for exhibitors. By mastering for, say, 10 or 14 ft-L, we set the bar for the future and present a reasonable picture in theatres today projecting at 4.5 ft-L – certainly not much worse than if mastering at 4.5 ft-L. Mastering at higher light levels would not only set the bar for the installation of brighter systems, but would also encourage the development of innovations that will lead to affordable high luminance 3-D in theatres.
The important step is to not standardize on a 3-D luminance level today. The 3-D industry is young, and labeling 4.5 ft-L 3-D systems as outdated or non-standard would be counter-productive. After seeing the demonstration, this appears to be an achievable goal.
