Many LED luminaires do not use high frequency drivers to eliminate flicker in the same way high frequency fluorescent lamp ballasts eliminate flicker. Shooting video in environments with  a lot of LED luminaires can produce video with distracting flicker. Viewers do not want to be distracted, and will switch off  if they see annoying flickering.

LED Lighting Video Recording Tips?

To eliminate flicker, for 120V 60Hz locations, the best shutter speeds to use are at multiples of 120, while at 220/230V 50Hz power locations, best shutter speeds are in multiples of 100. This Telegraph video seems to have been shot at 25 fps, which may be why a lot of annoying flicker can be seen. For flicker free video in 50Hz electrical environments, shooting at 50 or 100 fps should give best flicker free results, for 60Hz, 60 to 120 fps should give best results

For 50Hz 1/100, 1/50, 1/33, 1/25. 50 & 100 fps should = best results
For 60Hz 1/120, 1/60, 1/40, 1/30. 60 & 120 fps should = best results

This video should most likely have been recorded at 100 fps or 50 fps. In post-production there is no fix for this strobing effect. The only solution is to test other camera settings & re-shoot.

A best approach when Designing Architectural Lighting is to specify LED luminaires with high frequency, flicker free dimming drivers.

See full video & Telegraph article here: http://bit.ly/1cvuZxH

Many candelabra lamps look nothing like the candle flames they replace.

What a shame.

Good lighting provides the ‘lean forward moment’ found in film. The visual impression should be one of invitation, enjoyment and appealing appearance of space.

Too often candelabra lamps are nothing like the flames they replace.

Older style Incandescent candelabra lamps needed larger exterior glass envelopes to prevent the lamp glass from melting due to filament heat. Unfortunately many seem not to have understood the reason for this lamp construction solution and kept this larger, not to scale lamp size. It seems often fluorescent and LED sources are placed inside plastic large format candelabra lamp format envelopes…resulting in nothing but unsightly hideous glare bombs.

Good Lighting invites the viewer to enjoy the created space. Chandeliers essentially are  best only as decorative lighting. Attractive artistic shapes is what they can offer.

A dark, light story:

Ritz-Carlton Central Hong Kong.  Opened 1993. Demolished 2008.

A story told was the Interior Designer decided to be the Lighting Designer and essentially only used Chandeliers to light the hotel. The main lobby was dark & dreary and the room occupancy always low. A five-star hotel should never have had dark brooding lobbies and public circulation spaces. Overly bright chandeliers became glare bombs.  The best part of the hotel was the Health Club which had lighting designed by Tony Corbett. You could see the difference.

Lighting Design is all about what you want to see and how you want to see it. It has been said there are only three kinds of lighting. Bad Lighting which is obvious. Indifferent Lighting which while it may be technically correct, is uninspired, and Good Lighting invites the viewer to want to walk into a space to enjoy the created environment.  The viewer feels the instantaneous sensation of the film ‘lean forward moment’ and is compelled to enjoy the created space.

In 1975 Ingmar Bergman filmed the Magic Flute in the Drottningholm Palace’s 17th century Theatre.

Many years ago I traveled to see this Theatre and the chandelier candle replacement lamps. The candelabra lamps wobble independently mimicking the appearance of flames. Magic. You were instantly transported back in time, the created environment of the theater felt much the same as it would have had all chandeliers been lit with candles, but without the smokey smell smog.

This video compilation shows this unique lamp and heritage space. Seeing moving incandescent flame size lamps, was a magical experience.

Drottningholm Court Theatre Chandeliers

Unfortunately I have yet to see any decent LED chandelier candle replacement lamps which mimic the friendly flicker of flames…

Light & Colour – Conversations:
For insights on conventional light sources vs. LED sources and their colour rendering performance for Film & DSLR video see these tests.

I. The Academy of Motion Picture Arts & Sciences, Science & Technology Council Solid State Lighting Project

“The Academy of Motion Picture Arts & Sciences, Science and Technology Council has identified a need for an unbiased investigation of solid state lighting (SSL) technologies, which includes LED emitters, for motion picture production. Issues with SSL have been identified regarding its ability to supplement and integrate with existing lighting technologies such as tungsten, fluorescent, HMI, and Xenon that are currently used in the production of motion pictures. The primary purpose of this investigation is to provide the industry with data needed to properly evaluate the impact of using SSL, as well as to provide a framework for the evaluation of future light emitting technologies as they are developed. The Council’s current efforts are focused on providing the motion picture industry with accurate and previously unpublished radiometric and photometric measurements (e.g., spectral power distribution, radiant flux, luminous flux, etc.) typical of various LED light sources currently in use.”

Seven Symposium Videos:

  1. Jonathan Erland Speaks on the Science of Color
  2. Perception of Color
  3. Reproduction of Color
  4. Council Studies
  5. Measurements
  6. Emulsion and Color
  7. Summary

Six Lighting Test Shoots:

  1. Makeup Case
  2. Costume Case: Part 1
  3. Costume Case: Part 2
  4. Props Case: Part 1
  5. Props Case: Part 2
  6. Props Case: Part 3

IIa. Zacuto 2010 Shoot Out – Film Vs DSLR 2010 (episodes 1,2,3)

Zacuto Films presents, “The Great Camera Shootout 2010: a three part web series where gunslinging HD DSLRs face-off against legendary 35mm Film.” The webisodic series showcases the top performing hybrid HD-DSLR cameras: Canon: 5D MKII, 7D, 1D, 550D/T2i Rebel, Nikon D3s, Panasonic GH1 and compares the image quality of these cameras against the gold standard of 35mm film. In addition, the Canon 5D MKII test includes the new 24p firmware. “This was an enormous undertaking,” says Steve Weiss, Web Series Director, “and great care was to make this an apples-to-apples test with scientific accuracy behind it.”

Each webisode of the series features various controlled camera assessment tests which include: resolution, latitude, sensitivity, speed & ultra high speed, noise, color & green screen. The battery of tests were administered under strict controls and conducted by Robert Primes ASC, Gary Adcock, Philip Bloom, Jens Bogehegn and colorist Ryan Emerson.

See the reactions to this test following 2K screenings, where “HD DSLR is compared to 35mm Film”. The test results were projected in a 2K theatrical environment at three screening locations: Stag Theater at Skywalker Ranch, LucasFilms Ltd., AFI (American Film Institute) Theater in Hollywood and the FilmWorkers Astro Color Timing Theater in Chicago. Hear commentary from the screenings by top ASC, Hollywood, Indie Film and Event & Convergence Photographers.

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IIb. Zacuto 2011 Shoot Out – Film Cameras Vs High end Digital Film Cameras (episodes 1,2,3)

The 2011 shoot out includes new cameras & tests of Single Chip Camera Evaluation (SCCE) which is a large scale technical camera comparison administered by Robert Primes, ASC. Side by side comparisons of the newest cameras manufactured by Sony, Canon, Panasonic, Phantom, Weisscam, Nikon, Arri, RED as well as the gold standard of 35mm film are included.

Film Stock: 2-Perf & 3-Perf 35mm Motion Picture Film Demo

More on Colour Editing & Management in Post Production
From Shane Hurlbut:  7 Tips for HD Color Correction and DSLR Color Correction

A Short History of Compositing for Film & Video

Oscar Winner Petro Vlahos Inventor of the Ultimatte discusses his invention and how he used UV and Low Pressure Sodium lighting methods, which evolved into to the Blue & Green Screen chroma key compositing methods we use today.



A video demo from NAB 09

LED lumen maintenance curves decline due to LED use and thermal conditions.

All lamp lumen performance declines due to use. Lumen maintenance curve decline is also affected by the number of times a lamp is turned on & off, the thermal environment of the lamp and luminaire, and lamp ballast/driver electronics.

New research shows LED lumen performance declines due to heat without LEDs being turned on. During testing LEDs were turned on only for short duration lumen measurement data collection.

This has large implications for exterior LED lighting where high ambient temperatures are present, as is typically found inside luminaires exposed to direct sunlight during daytimes when luminaires are not on.

The higher the ambient temperature, the faster LED lumen performance declines. Not all high brightness LEDs perform the same way.  Different manufacturer’s LEDs exhibit different rates of decline.  Variation in lumen performance decline must be due to differences in LED manufacture technique and material.

I am interested to review Electron microscopic time-elapse images & data collected at different points along the lumen maintenance curve. No doubt, there is something new to discover to improve manufacturing technique & fabrication for more robust LEDs.