Jump to content


Photo

Motion picture agitation during development

developing agitation color film

  • Please log in to reply
3 replies to this topic

#1 Philip Kral

Philip Kral
  • Basic Members
  • PipPip
  • 90 posts
  • Cinematographer

Posted 22 May 2017 - 04:01 PM

Strange question for those members who own and/ or work in motion picture film labs: How does the film get agitated during development?

 

When one develops still film at home, you must "agitate" the film by either shaking, stirring or inverting the container containing the film and the developer. The process is supposed to be crucial to ensure the film is constantly being exposed to fresh developer. Naturally, the jumbo processing machines must use a different method.

 

Does the processing machine used for movie film utilize some way of doing this? Or because the film strip is constantly moving through the developer, that itself provides constant re-exposure to fresh(er) developer?


  • 0

#2 Dirk DeJonghe

Dirk DeJonghe
  • Basic Members
  • PipPipPipPip
  • 612 posts
  • Industry Rep
  • Kortrijk,Belgium

Posted 22 May 2017 - 11:50 PM

There are submerged spray nozzles impinging fresh developer on the emulsion side every few seconds. There is one pump for heating, circulation and filtration of the developer and another powerful pump only for agitation. Movement of the film itself is not enough to insure streak-free processing.
  • 0

#3 Gregg MacPherson

Gregg MacPherson
  • Basic Members
  • PipPipPipPip
  • 1925 posts
  • Other
  • New Zealand

Posted 23 May 2017 - 02:49 AM

In the gap between stiil film development and continuous motion picture processors,  the lomo tank exists.  It just needs turning on the spindle with your fingers.  Similar I suppose to processing stills.  Years ago,  I had friends with a small continuous B&W processor which used aquarium pumps to circulate the solution continuously.  The basic ideas are brutally simple.  The professional labs will have more sophisticated methods with better measurement.


  • 0

#4 Robert Houllahan

Robert Houllahan
  • Sustaining Members
  • 1615 posts
  • Industry Rep
  • Providence R.I.

Posted 23 May 2017 - 11:57 PM

Yeah as Dirk said, there are large powerful pumps and a set of wands between the film loops in the tank racks to agitate / circulate the developer.

 

Our Photomec has two 3-phase motor pumps with 2" intakes and outlets.


  • 0



FJS International, LLC

Media Blackout - Custom Cables and AKS

Wooden Camera

Broadcast Solutions Inc

Gamma Ray Digital Inc

The Slider

Paralinx LLC

Tai Audio

CineLab

Glidecam

Visual Products

Metropolis Post

CineTape

Abel Cine

Rig Wheels Passport

Ritter Battery

rebotnix Technologies

Aerial Filmworks

Willys Widgets

Technodolly

CineLab

rebotnix Technologies

Glidecam

Metropolis Post

Tai Audio

CineTape

Abel Cine

Media Blackout - Custom Cables and AKS

The Slider

Paralinx LLC

Aerial Filmworks

Willys Widgets

Rig Wheels Passport

Gamma Ray Digital Inc

Technodolly

FJS International, LLC

Wooden Camera

Visual Products

Ritter Battery

Broadcast Solutions Inc