Cinema Standards Measurement System™ (CSMS™)
Runco has replaced the ANSI-lumen specification as the primary measurement standard for its projectors and has adopted the foot-Lambert measurement procedure for measuring the light output of its projection products.
Runco is once again striving to enhance and broaden the Home Theater™ video market by changing the technical specifications of its video displays . Runco is doing this to realistically reflect the needs of sophisticated consumers concerned with high fidelity HDTV and Digital Film reproduction.
The specification standards in use by Runco and others until now, were designed for industrial video displays and by default have been universally used to describe Home Theater™ products throughout the industry.
The objectives for good Home Theater™ video are different than those for industrial presentations. Therefore the specifications that we currently employ do not convey the proper performance characteristics of what makes a good movie picture or a realistic HDTV image.
Why this is necessary:
“We feel that the measurement criteria associated with light output for fixed-pixel technology specifications is inappropriate for Home Theater™ applications,” says Sam Runco, President and founder of Runco International, “The traditional ANSI-lumen method for measuring brightness can be an accurate quantitative measurement but does not describe the quality of an image for home theater. We have decided to use a measurement system that is a true representation of how bright an image is in reference to something everyone can understand – a movie theater.”
Runco further stated that “By using the foot-Lambert measurement specification we can communicate to the customer that the image in his home theater might be 1.5x brighter for example, than the image at his local cinema, which is much more meaningful than trying to explain how bright 1000 ANSI-lumens will appear on an 8’ wide screen.”
The method of measurement known as foot-Lamberts, is a measurement related to the brightness of a particular image and is equal to 1 lumen per sq. foot of screen surface. A Spectral Radiometer is required to perform this measurement. The SMPTE (Society of Motion Picture and Television Engineers) specification for a film-type movie theater is a minimum of 16 foot-Lamberts of brightness.
As research by Lucasfilm Ltd’s, Theater Alignment Program has determined, movie theaters typically struggle or fail to achieve this brightness specification, even with the high wattage lamps in their film projectors. Since the screen size is generally much smaller for Home Theater™, it is possible to consistently achieve 16 foot-Lamberts and most of the time much higher brightness with Runco projectors.
How this affects the consumer:
The purpose of our change to the more appropriate ‘Cinema Standards Measurement System™’ (CSMS™) specification is to make the information on our spec sheets relevant to the consumer. The change to foot-Lamberts will make for an easy comparison between how bright the average movie screen is, relative to our projectors. We will include the color temperature at which our light output was measured, as well as screen gain used. This is critical because increasing color temperature increases brightness as do higher gain screens. Unfortunately an overly exaggerated color temperature ruins color fidelity in the type of pictures necessary for Home Theater™.
Runco’s changes in video display specifications make it possible for the consumer to easily relate the picture performance of our products to that of a local film cinema.
Home Theater is still evolving:
Discussing Runco’s departure from the ANSI-lumen method presently in use by the industry, Chuck Turigliatto, Vice President of Sales and Marketing explains, "the Home Theater™ industry is still a 'work in progress' and as one of its creators, we at Runco view ourselves as a guardian of this industry. When we feel strongly that something is incorrect or needs a more appropriate direction, we will not hesitate to use Runco as a platform to initiate that change on behalf of the industry. The testing methods that have been used came from an entirely different industry and were applied in Home Theater™ more by default than by adoption. Our methods were designed to be an objective measurement that is more appropriate for Home Theater.™”
Projection light output basics:
- The projector outputs a fixed amount of light
- As screen size increases, foot-Lamberts decrease
- Gain on the screen will increase the foot-Lambert reading
- Negative-gain screens used for better black levels will decrease foot-Lambert value
- Doubling the screen size diagonally results in 1/4 the brightness of the smaller screen
- A formula can be assigned to every projector to calculate its true foot-Lambert measurement capability for any screen
Runco will continue to provide ANSI-lumen specifications as a secondary means of comparison with those products which have not yet been converted to the foot-Lambert system.