Kodachrome

Kodachrome photo of Shaftesbury Avenue from Piccadilly Circus, in the West End of London, circa 1949. Photo by Chalmers Butterfield

A typical plastic 35mm Kodachrome slide from the 1990s showing logo and text on the reverse side.

Kodachrome is the trademarked brand name of a type of color reversal film that was manufactured by Eastman Kodak from 1935 to 2009.^[1] Kodachrome was the first successfully mass-marketed color still film using a subtractive method, in contrast to earlier additive "screenplate" methods such as Autochrome and Dufaycolor, and remained the oldest brand of color film.

Over its 74-year production, Kodachrome was produced in formats to suit various still and motion picture cameras, including 8mm, Super 8, 16mm, and 35mm for movies and 35mm, 120, 110, 126, 828, and large format for still photography. It was for many years used for professional color photography, especially for images intended for publication in print media.

Kodachrome requires complex processing that cannot practically be carried out by amateurs. The film is sold with processing included in the purchase price except in the United States, where a 1954 legal ruling prevents this.

Kodachrome is appreciated in the archival and professional market because of its color accuracy and dark-storage longevity. Because of these qualities, Kodachrome is used by professional photographers like Steve McCurry and Alex Webb. McCurry used Kodachrome for his well-known 1984 portrait of Sharbat Gula, the "Afghan Girl" for the National Geographic magazine.^[2] It was also used by Walton Sound and Film Services Ltd in the UK in 1953 for the only official 16mm film of the coronation of Her Majesty Queen Elizabeth the Second. Subsequent prints for sale to the public were also produced using Kodachrome.^[3]

As digital photography progressively reduced the demand for film in the first decade of the 21st century, Kodachrome sales steadily declined. On June 22, 2009 Eastman Kodak Co. announced the end of Kodachrome production, citing declining demand.^[4] Many Kodak and independent laboratories once processed Kodachrome, but only one Kodak certified facility remains: Dwayne's Photo in Parsons, Kansas, where existing film stock will be developed until the end of 2010.

History

The additive methods of color photography, such as Autochrome and Dufaycolor,^[5] were the first practical color processes; however, these had disadvantages. The réseau filter was made from discrete color elements that became visible upon enlargement, and the finished transparencies absorbed between 70% and 80% of light upon projection, requiring very bright projection lamps, especially for large projections. Using the subtractive method, these disadvantages could be avoided.^[6]

Kodachrome was invented in the early 1930s by two professional musicians, Leopold Godowsky, Jr. and Leopold Mannes,^[7] hence the comment that Kodachrome was made by God and Man.^[8][9] It was first sold in 1935 as 16 mm movie film. In 1936 it was made available in 8 mm movie film, and slide film in both 35mm and 828 formats.^[10] Kodachrome would eventually be produced in a wide variety of film formats including 120 and 4x5, and in ISO/ASA values ranging from 8 to 200.^[11]

Kodachrome was featured in the 1973 Paul Simon song "Kodachrome", and Kodachrome Basin State Park in Utah, has been named after it — the only park named for a brand of film.^[2]

Characteristics

Emulsion

Kodachrome is fundamentally different from other transparency and negative color films that have dye couplers incorporated into the emulsion layers. Kodachrome is unique because it has no dye couplers in the emulsion; these are introduced during processing.^[12] Without couplers, the emulsion layers are thinner, causing less light scattering and allowing the film to record a sharper image.^[13] A Kodachrome slide is discernible by an easily-visible relief image on the emulsion side of the film.^[14] Kodachrome has a dynamic range of around 8 stops, or 3.6-3.8D.^[15]

Archival stability

When stored in darkness, Kodachrome's long-term stability under ordinary conditions is superior to other types of color film; images on Kodachrome slides over fifty years old retain accurate color and density. It has been calculated that the least stable color, yellow, would suffer a 20% loss of dye in 185 years.^[16] This is because developed Kodachrome retains no unused color couplers. However, Kodachrome's color stability under bright light, for example during projection, is inferior to E-6 process slide films; Kodachrome's fade time under projection is about one hour, compared to Fujichrome's two and a half hours.^[17]

Unprocessed Kodachrome may survive long periods between exposure and processing. In one case, several rolls were exposed and then lost in a Canadian forest; upon discovery 19 years later they were processed and the slides were usable.^[18]

Digital scanning and resolution

A 35mm Kodachrome transparency, like other 35mm transparencies on films of comparable ISO rating, contains an equivalent of approximately 20 megapixels of data in the 24 mm x 36 mm image.^[19] Scanning Kodachrome transparencies can be problematic because of the film's tendency to scan with a blue color cast.^[15] Some software producers deliver special Kodachrome color profiles with their software to avoid this. However, an IT8 calibration with a special Kodachrome calibration target is necessary for accurate color reproduction.^[20]

Typically, dust, scratches and fingerprints on the slide are detected and removed by a scanner's software. Many scanners use an additional infrared channel to detect defects, as the long wave infrared radiation passes through the film but not through dust particles. Kodachrome interacts with this infrared channel in two ways. The absorption of the cyan dye extends into the near IR region, and thus this layer is opaque to IR.^[21] Kodachrome also has a pronounced relief image that can affect the IR channel. These effects can sometimes cause a slight loss of sharpness in the scanned image when Digital ICE or a similar infrared channel dust removal function is used.^[22]

Processing of Kodachrome films

Kodachrome processing has undergone four significant alterations since its inception.^{[citation needed]} The current process is designated Process K-14.^[23] The process is complex and exacting, requiring technicians with extensive chemistry training, as well as large, difficult-to-operate machinery. This effectively precludes amateurs or small laboratories from processing Kodachrome.^{[citation needed]}

First, the antihalation backing is removed with an alkaline solution and wash. The film is developed using a developer containing phenidone and hydroquinone, which forms three superimposed negative images, one for each primary color.^[23]

After washing out the first developer, the film undergoes re-exposure and re-development stages. Re-exposure exposes the silver halides that are not developed in the first developer, effectively fogging them. A color developer then develops the fogged image, and exhaustion products form a color dye in the color that is complementary to the layer's sensitivity. The red-sensitive layer is re-exposed through the base of the film with red light, and then re-developed with a developer forming cyan dye. The blue-sensitive layer is re-exposed through the emulsion side of the film with blue light, and then re-developed with a developer forming yellow dye. The green-sensitive layer is re-developed with a developer that chemically fogs it, and forms magenta dye. The two light re-exposures must be carefully controlled, so that they do not cause re-exposure of the green-sensitive layer.^[23]

Following color development, the metallic silver is converted back to silver halide salts using a bleach solution. The film is then fixed, making these silver halides soluble and leaving only the final dye image. The film is finally washed to remove chemicals which may cause deterioration of the dye image, dried and cut.^[23]

Legality of paid processing

Due to the complexity of its processing, Kodachrome was initially sold at a price which included processing by Kodak^[24] An envelope was included with the film, in which the photographer would send the exposed film to the nearest of several designated Kodak laboratories.^[25] The film was processed, mounted in 2" x 2" cardboard mounts in the case of 35 mm slides, and returned by mail to the sender.

After 1954, as a result of the case United States v. Eastman Kodak Co., this practice was prohibited in the United States as anticompetitive. Kodak entered into a consent decree, ending this product tying practice in the United States, and allowed independent processing laboratories to acquire the chemicals needed to process Kodachrome films.^[26][27]

Decline

The use of slide film in general declined in the 1980s and 1990s which, combined with competition from Fuji's Velvia slide film, caused a drop in Kodachrome sales.^[2] Kodachrome products were gradually discontinued and on June 22, 2009, Kodak announced Kodachrome would no longer be manufactured.^[28][29]

Many Kodachrome processing laboratories, both Kodak-owned and independent, closed because of the decreasing volume of business. The loss of processing availability further accelerated the fall in Kodachrome sales.^[2] On July 25, 2006 extensive documentation about Kodak's Lausanne Kodachrome lab's impending closure was sent to the European Parliament by the Dutch office of the European Parliament because, although located in Switzerland, the facility served all of Europe and its closure would affect European photographers. The Parliamentary committees for Culture and Education,^[30] and for Internal Market and Consumer Protection^[31] studied the matter.

Kodak no longer processes Kodachrome film and instead subcontracts the processing work to Dwayne's Photo, an independent facility in Kansas, which as of 2009 is the only remaining Kodachrome processing facility.^[32] Dwayne's processing of 35 mm films is fully endorsed by Kodak, but Dwayne's Super-8 process is not endorsed because it requires more agitation.^[32] Films sent for processing in the U.S. are mailed directly to Dwayne's, while those sent for processing in Europe are sent to the Lausanne facility's address, whence they are forwarded to Dwayne's.^[33]

Kodak had previously attempted to increase the availability of K-14 processing through the K-Lab program, where small labs equipped with smaller Kodak processing machines would supplement Kodak's own processing services.^[34] These labs have all closed.

Dwayne's Photo has announced^[35] that they will continue processing Kodachrome through the end of December, 2010 and that their supply of Kodachrome film has run out. The end of professional processing will signal the final end of the Kodachrome era.

Recently-discontinued Kodachrome products

• Kodachrome 64 film in 120 format was discontinued in 1996.^[11]

• Kodachrome 25 was discontinued in 2002. Many point to the introduction of Velvia or the decline in quality of processing as the reason for its demise.^[36]

• Kodachrome 40 in the Super 8 movie format was discontinued in June 2005,^[37] despite protests from filmmakers.^[38] Kodak launched a replacement color reversal film in the Super 8 format, Ektachrome 64T, which uses the common E6 chemistry.^[39]

• Kodachrome 200 was discontinued in November 2006. The last emulsion batch was numbered 2672, labeled with an expiration date of September 2008.^[40]

• Kodachrome 64 and Kodachrome 64 Professional 135 format were discontinued in June 2009.^[41][42]

Product timeline

^[11]

See also

• 135 film
• List of products manufactured by Kodak

References

External links

Official Kodak information

• Technical data on Kodachrome 40 movie film
• Kodachrome Discontinuation Notice

Other resources

• Dwayne's Photo Worldwide Kodachrome processing facility.
• Kodachrome Slide Dating Guide.
• The Kodachrome Project.
• Club by and for Kodachrome users.

Processing of obsolete Kodachrome types K-11 and K-12:

• Film Rescue International Worldwide
• Process C-22 UK and Europe
• Old Film Processing UK and Worldwide