On April 3 2008, John Galt, Panavision Senior Vice President, Advanced Digital Imaging, and Larry Thorpe, National Marketing Manager, Canon Broadcast & Communication Division, presented their views on a realistic, scientifically valid way to gauge the quality of recorded pictures that belies the theory that “it’s all about the pixels.” The sessions were held at Panavision’s world headquarters in Woodland Hills, and taped in high definition video with three cameras before a live audience of cinematographers, and other craftsmen, studio executives and the media.

What did we learn?

The key issue, especially for those of us dealing with customers at Panavision, is that the pixel output of a camera system has little to do with final image performance. Production staffs who judge camera performance purely on pixel counts may be short-changing themselves on the actual quality of the images that are finally seen on big and little screens.

Marketing pixels come at a price!

By contrast, Genesis has a 12.4 million photo site sensor, produces content superior to what is commonly called a “4K” camera, but through “super-sampling” our final output which is only 6 megapixels (or an 8 megabyte DPX frame). In other words: Same or better picture quality with far less overhead.

Instead of using pixels to determine picture quality, Galt and Thorpe recommend the MTF (Modulation Transfer Function) System—a resolution system that takes into account multiple factors in the actual production of any given image such as measurable characteristics of lenses, the sensor used in actual recording, intermediate film stocks, even the projector lens—digital movie makers have tools to help them gauge precisely what effect each step has on the production of that final image.

Once movie makers understands how variables such as MTF, Nyquest calculations, Beyer pattern, the scientific difference between sharpness and resolution have real impact on digital pictures—all explored in this symposium by Galt and Thorpe--they will be better equipped to choose the right cameras and associated technologies to produce the pictures they want.

“Demystifying Digital Camera Specifications” is a meaningful way to understand clearly where each part of the movie-making process plays its part.

Part 1 discusses the following topics: 
A short history of CCD/CMOS development, Sub-sampling and Super-sampling, HD lens and camera design strategies, Photosites - the tradeoff between resolution, dynamic range, and noise, Digital output signals from cameras, UHDTV, 2K and 4K cameras, and DCI Standards for 2K and 4K.

Part 2 discusses the following topics: 
The Nyquist Theorem, linking optical and digital sampling, The implications of Fill factor and optical low pass filtering, The Nyquist boundaries of of motion pictures, and Limiting resolution.

Part 3 discusses the following topics: 
Introduction to MTF, Introduction to an individual element’s contribution to final MTF, Transferring contrast, Cascading MTFs, Introduction to Otto Schade, Perceived picture sharpness and MTF, Edge Sharpness, image textures, and resolving power.

Part 4 discusses the following topics: 
Pixels are not resolution, Practical measurements of MTF, Introduction to sinusoidal MTF charts, The Panavision sinusoidal MTF Chart, MTF benches for measuring lenses, Cascaded MTF of a DI, Sensor MTF response, Depth of Field, MTF measurements of real world lenses.

Part 5 discusses the following topics: 
Line pairs per Millimeter, Differences between HDTV and SDTV lens standards, a demonstration of the MTF-Aliasing dilemma using three chip cameras, Loading the imager MTF into the digital container.

Part 6 discusses the following topics: 
The resolution metric for a Bayer pattern sensor, Diagonal sampling Bayer pattern sensors, Optical lowpass filter options for single Bayer pattern sensors.

Part 7 discusses the following topics: 
Spectral response, Camera color balance: Daylight v. Tungsten, Digital Intermediate MTF comparison between Genesis and 5218, Bayer vs. RGB striped sensors.

	Part 1 - What's in a Pixel?	126,273 Kb
	Part 2 - Keeping Harry Happy	87,477 Kb
	Part 3 - Introducing MTF	110,900 Kb
	Part 4 - Diving Deeper into MTF	123,264 Kb
	Part 5 - Three Chip Digital Cameras	114,766 Kb
	Part 6 - Single Sensor Cameras	67,361 Kb
	Part 7 - Single Sensor Cameras Continued	130,553 Kb

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