Hank Mahler, father of SMPTE colour bars and developer of triax, dead at 84

October 5, 2021 marked the passing of a true motion picture and television engineering icon, Henry (Hank) Mahler at age 84. Mahler played a key role in developing a number of industry standards and systems, including SMPTE colour bars and the triax cable system. After graduating from Stevens College in the US with a BSEE, Mahler joined the CBS Technology Center in Stamford, Connecticut. One of his first projects at the technology center was destined to become one of the most widely used audio processing technologies: the CBS Laboratories Audimax and CBS VoluMax, which were considered the “gold standard” for audio processing used in the AM/FM and television broadcasting industry.

Mahler also received a patent for developing an audio meter capable of indicating 60dB of audio range while the typical VU meter displays approximately a third of that range. Mahler also worked on the CBS 360 record player, which was a stereo self-contained solid state audio recorder.

Although Mahler’s first projects at the CBS Laboratories were audio projects, his expertise was not confined to audio systems and circuits. His next big project was to develop the first black and white slow motion and stop action system, which recorded up to 20 seconds of video. In 1966, the National Academy of Arts and Sciences (NATAS) awarded CBS an Emmy for the stop action playback system.

During the early days of colour television, maintaining timing and calibration of the analogue colour systems was a challenge. To aid in this calibration process, Mahler developed the SMPTE colour bars and was recognised by the National Academy of Television Arts and Sciences in 2002 for standardizing and building the first SMPTE color bar generator.

Mahler ’s next project was the digital noise reducer, which received an Emmy Award in 1977 for its innovative processing capabilities.

As digital video became more prevalent in television production, Mahler, working with a team at CBS Labs, created “CBS Action Track.” This permitted the viewer to see the path of key sporting plays, such as the path of a golf ball on the green or the curve of a football in the air.

While the CBS Field Sequential Colour System was supplanted by the NTSC Colour Standard, the field sequential colour camera did make notable contributions to image capture. Mahler worked on the field sequential colour camera and demonstrated it to the Westinghouse Corporation, the subcontractor for the NASA colour moon camera on the Apollo 14 mission, which provided the first colour images on the moon.

Mahler ’s work was not just confined to audio and video. He developed the first colour light amplifier and image intensifier used at the 1972 political conventions, which was mounted on a 16mm film camera.

During the early days of analogue NTSC color television, telephone video circuits were quite expensive. To maximise the use of these circuits, Mahler next worked on a project that allowed for two colour television signals to be simultaneously transmitted and received on a single video circuit. The STRAP (Simultaneous Transmission and Reception of Alternating Pictures) was used by CBS News to maximise their newsgathering capabilities.

Mahler also was part of the engineering team that revolutionised sports production through the development of the triax coaxial camera system, which received an Emmy award in 1992.

After the CBS Technology Center was closed, Mahler continued his career at CBS as the Associate Director of Advanced Technology in the New York CBS Engineering Lab. Mahler was part of the engineering team that launched the CBS TV Network’s HD service in 1998 that included John Glenn’s return to space and three NFL games. He continued to make invaluable contributions to the development of High Definition television and review of major capital equipment purchases at the CBS Television Network, as well as owned-and-operated TV stations.

In the early days of High Definition production, many in the motion picture and television industries were reluctant to give up their tried and true method of capturing the images on 35mm film. Mahler ’s research (1985 -2003), and seminal 2003 paper on “The Image Resolution of 35mm Cinema Film in Theatrical Presentation” shook up the Hollywood production community. Mahler ’s research and testing was part of the ITU-R Study Group 6 work related to Large Screen Digital Imagery (LSDI). A test was performed to determine the end-to-end resolution provided by 35mm cinema film projection in typical motion picture theater. A resolution test pattern was photographed on a 35mm negative film stock typical of those used for the production of feature films, and 35mm inter-positive, inter-negative, release prints and answer prints were struck from that negative in conformity with cinema routines.

This research provided definitive proof that the 1920×1080 High Definition video format could deliver comparable or better quality to that of 35mm film in the cinema and ultimately to the consumer’s home.

Today, the vast majority of motion picture and television production is acquired electronically in High Definition or UHDTV.

Many a vendor dreaded having their equipment evaluated in the CBS Engineering Lab, because Mahler would inevitably uncover issues that required them to “go back to the drawing board.”  However, in the end, when the equipment passed Mahler ’s muster and received the CBS Engineering Lab “Good Engineering Seal of Approval,” it was a world class product and was recognized by the industry as being top of the line in its category.

If you wanted to stay on Mahler’s good side, you would never interfere with his coffee breaks, which he would announce VERY loudly in his deep baritone voice, “COFFEE.” The lunch time volleyball games at the CBS Laboratories in Stamford, Connecticut, turned Mahler into a jovial, but fierce competitor. There were many CBS Lab colleagues that fell prey to HMahler ’s practical jokes, and they reciprocated by sending him a fake termination “pink slip.” His office was plastered, not with his technological accomplishment, but with family photos, indicating what was important in his life. Mahler’s most endearing qualities were his humble nature, engaging smile and willingness to use his vast engineering knowledge to educate his fellow engineers. He will be missed by his immediate family and by his CBS family who had the privilege of working with him for over 60 years.