Kodachrome's Nice Bright Colors Fade To Black

Kodak has announced the final production run of Kodachrome 64 slide film. The irony is that vintage Kodachrome slides and movies will probably outlast modern digital images and prints by decades.

First introduced in 1935, the film is special in that the color dyes are added in three layers during the developing process. The technique is an environmental nightmare, but results in vibrant, colorfast images that should last a century or more without significant fading. Dwayne's Photo in Parsons, Kansas will process the film until the end of 2010.

[I thought you might appreciate this piece about Kodak's last European lab. It closed a few months after this article appeared in a 2005 issue of smallformat.]

They all land here

The only Kodachrome 40 laboratory in Europe

Text: Jürgen Lossau

It is just after 7 a.m. in the town of Renens, close to Lausanne.  The reception area at the Swiss Kodak laboratory is still unoccupied.  A cat makes herself at home next to the heater and casts a bored gaze at the guest waiting in front of the locked glass door.  The guest calls François Bercher, the man who will guide him through Europe’s only Super 8 laboratory for Kodachrome 40.  The shift is already half over for Bercher, the lab’s electronics & systems engineer.  Kodak’s processing day begins at 4 a.m. for Kodachrome, Ektachrome, 16mm and 35mm slides.  At the end of 2004, the lab stopped handling digital prints, negative film and posters.  At one time, 150 people worked here, including Kodak’s Swiss distribution group.  Now, 70% of the space is empty.

Bercher turns out to be a great fan of Super 8.  “Kodachrome 40 is still the best material for movie amateurs when it comes to quality and grain,” he explains.  But the film is not easy to process.  “We need 14 baths,” says Bercher, “while three solutions are sufficient for Ektachrome.  You can almost process that stuff yourself.”

With Kodachrome 40, it isn’t an option.  We enter the impressive darkroom, the secret domain of the chemists.  “This is another world, the reversing process,” laughs Bercher.  Only a few can master this elaborate process, where every second counts and maintaining the correct temperature is critical.  Rene Agassis sits in a small glass enclosure.  He is the master of Kodachrome and Ektachrome, the manager of processing.  “All Super 8 cartridges have been coming to us from Germany for 11 years, but we also receive many movies from England, Sweden and Switzerland.  There were about 100,000 last year,” Agassis calculates from his lists.


18 processing machines in Stuttgart

This reminds Bercher of his time in Stuttgart, when he learned how to set up processing machines.  “In 1976, we installed 18 machines there. By the early 1990s, Super 8 was finished in Stuttgart."  Apart from the Swiss lab, only the USA has a laboratory for Kodachrome 40, but it doesn’t belong to Kodak. Dwayne’s Photo in Parsons, Kansas is the only lab on Earth still able to perform this highly complicated process.

Back to the darkroom.  Agassis threads an almost endless strip of film that has been spliced together from individual cartridges onto a huge 900 meter reel.  The time the film spends in each bath depends on the depth at which a secondary roller hangs in the tank before sending the moving film back to the surface.  The processing solutions are pumped through a complicated pipe system into the tanks.  The mixture in each tank consists of older chemicals to which freshly mixed solution is continuously added, while old developer and fixer are simultaneously pumped out.  “This way, the mixing ratio is always exactly the same”, emphasizes Bercher.

The developing process is interrupted twice with reverse exposure.  The film runs past a lamp to make the negative into a positive.  Perhaps this should be explained a little better: The film consists of a negative picture captured in three silver layers.  With Kodachrome 40, the color dyes come from the developing process, not the film itself.  Therefore, Kodachrome is initially processed into a negative that is quasi black and white.  The material is then bleached, which destroys the silver image.  The color layers are sensitized through exposure to light (reverse exposure).  This activates a layer that absorbs the corresponding color from the developer.  The lighting is set up so that it can only activate a specific layer.

Complicated reverse exposure

What makes the entire process so complicated is the need for precise control of the individual processing solutions.  They must only be active for the appropriate color layer and not bleed to another layer to wreak havoc there.  The diffusion of colors in the film is no less complex.

Bercher strokes across the rollers, especially proud of the low tension the film is exposed to.  “That’s only a few grams.”  Flexibly suspended rollers were especially important in days gone by, when sound film was still processed.  Any stretching of the film material inevitably damaged sound quality.

“What happens if the film breaks during processing?” I wanted to know.  Bercher emphasizes that something like this typically happens only once a month.  Suddenly, a siren sounds for the slide processing machine next door.  Three men appear immediately to fix the mishap.  A perforated plastic band is tacked between the torn ends, and the machine can continue.  Obviously, today is the one day in the month when a film breaks.  This must be an example of the demonstration effect, where things break in the presence of an inquisitive visitor.

“By the way, we glue our splice points with ultrasound for durability,” Bercher redirects.  “In the past, we heated the film ends to 160 to 180 degrees Celsius and then applied the glue, but the modern method produces more durable results.”

400 films per hour

René Agassis joins the conversation again.  He offers impressive statistics:  “A Super 8 film runs through the entire system in 23 minutes.  It runs for a distance of 2.5 kilometers.  That’s a total of 103 meters per minute.  We develop 400 films per hour here.”  But the actual processing lasts only one to two hours per day.  The rest of the time is spent with setup and finishing work.

The processing machine is 31 years old.  “When something breaks, we still have many spare parts from machines we have taken out of service.  Sometimes, we have to rebuild”, states Bercher.  He descends to the floor below with me, where chemical engineer Sandro Marchili is mixing individual solutions.  “This is where we mix all of the baths according to specific formulas.  These are not finished products,” assures Marchili, happy to have a surprise visitor.  He checks the processing quality in his office.  A specific film strip is processed and evaluated every half hour.  Marchili examines the scanned acetate material at his computer.  “When all the values are between these two bars”, he nods with satisfaction while looking at the screen, “then everything is alright.”   There are men and women sitting in other booths glancing quickly at slides or watching film rattle through a small Bauer projector.

How do they keep track of it all?

After processing, the dried film strips are loaded back onto a giant reel and run through a splicing machine.  As fast as the wind, the Super 8 film is sliced back into 15 meter lengths and loaded onto familiar little black reels that are magically packed into the sender’s original bag.  And then: Into the mail.

Kodak has agreements with some postal services to return processed film directly to the sender from Switzerland, duty-free.  In other cases, the yellow bags are collected into large packages and sent to the appropriate Kodak branch.  If someone accumulates and sends in more than three cartridges at a time, these can be returned together as an individual package.

How do they make sure the film isn’t mixed up when it comes out of the sender’s envelope, to be spliced onto the large processing reel?  Easy:  Matching numbers are imprinted on the bag and film, and they remain in the same sequence at all times.  When the individual bags and processed 15 meter reels are reunited at the end, the numbers should match.

When films get mixed up or are poorly labeled, it can difficult to find the correct photographer.  Characteristics of the images are meticulously recorded using a PC to enable keyword searches.  If only fragments of an address remain on a sender’s envelope, the bits that remain may provide useful clues such as a Zip Code extracted from the postmark.

Two hours have passed.  It is now really bright outside.  François Bercher escorts me to the reception area, which has been occupied for some time in my absence.  The cat has long since left her cozy spot by the heater to go hunting.  “She will sneak back in tonight,” says Bercher, “No one knows how she does it.”