Jump to content


Photo

UVC Purification Lamps / HNS Germicidal lamps


  • Please log in to reply
2 replies to this topic

#1 Tebbe Schoeningh

Tebbe Schoeningh
  • Basic Members
  • PipPipPip
  • 117 posts
  • Cinematographer
  • Buenos Aires, Berlin

Posted 28 September 2010 - 06:10 AM

Hi all,

I´m gonna be shooting in a slaughterhouse and I noticed that they are using special HNS lamps to desinfect the ambience.

Aparently those lights are working with an extended UV-spectrum and they look really magenta.

Does anyone know if there are special UV-Cut filters to use in camera for this occasions?

Thanks in advance

Tebbe
  • 0

#2 Michael E Brown

Michael E Brown
  • Basic Members
  • PipPip
  • 56 posts
  • Gaffer

Posted 28 September 2010 - 10:05 PM

Hi all,

I´m gonna be shooting in a slaughterhouse and I noticed that they are using special HNS lamps to desinfect the ambience.

Aparently those lights are working with an extended UV-spectrum and they look really magenta.

Does anyone know if there are special UV-Cut filters to use in camera for this occasions?

Thanks in advance

Tebbe


Schneider has a UV-410 filter that cuts rays below 410 nm. Looking at the spec sheet for Osram's HNS lamps, they put out UVC at 254 nm and in some versions at 185 nm also.

Something to be careful of perhaps is using wide angle lenses with real UV cut filters that have a special coating (as opposed to just clear glass, which also cuts some UV by nature). Apparently with lenses over 60 degrees FOV, the edge rays pass thought the filter at a different enough angle from the center rays to cause a blue shift on the edges. Probably similar to the effect of shining a light through a dichroic glass filter - the color will shift depending on the angle of the rays striking the coating. With a blue dichroic, rays that hit the coating at a 45 degree angle shift towards purple.

What format are you shooting? If all the lights are this same type, you may be able to white balance the magenta cast out.

Edited by Michael E Brown, 28 September 2010 - 10:07 PM.

  • 0

#3 John Sprung

John Sprung
  • Sustaining Members
  • 4635 posts
  • Other

Posted 29 September 2010 - 01:12 AM

This is the kind of thing that really demands shooting tests, not theory.




-- J.S.
  • 0


Glidecam

Paralinx LLC

Abel Cine

Ritter Battery

Visual Products

The Slider

Willys Widgets

CineTape

Aerial Filmworks

Wooden Camera

Media Blackout - Custom Cables and AKS

rebotnix Technologies

Gamma Ray Digital Inc

Tai Audio

Metropolis Post

Opal

Broadcast Solutions Inc

FJS International, LLC

Technodolly

Rig Wheels Passport

CineLab

Visual Products

rebotnix Technologies

Wooden Camera

Opal

Media Blackout - Custom Cables and AKS

Rig Wheels Passport

Glidecam

Metropolis Post

Gamma Ray Digital Inc

Paralinx LLC

Willys Widgets

CineTape

Tai Audio

Abel Cine

Aerial Filmworks

The Slider

Technodolly

Ritter Battery

FJS International, LLC

CineLab

Broadcast Solutions Inc