Kodakrome slide film

Jocelyn Evans <jocelyne [at] unimelb__edu__au> writes

>We have been using Kodakrome colour slide film (200 speed) for our
>before and after treatment colour images; unfortunately it is no
>longer readily available in Australia.  We'd like to hear of
>people's thoughts regarding the archival-quality of other colour
>slide films, or of people's experiences in changing over to digital
>imaging (such as issues surrounding storage of images and
>maintaining consistency in quality).

Apart from Kodachrome, for which there is no equal in dark storage;
for conventional photography, there are a number of modern high
quality colour transparency emulsions with reasonable life
expectancy in dark storage and better life expectancy than
Kodachrome in projection. Assuming you are using Kodachrome 200
rather than 64 or previously 25 to get a lower overall contrast, I
would recommend Fuji Astia 100. It has accurate colour, medium
contrast and fine grain. In addition it has extraordinary
reciprocity characteristics, such that extended exposure for 30
seconds or so produces no discernible colour distortion and requires
no alteration in exposure. It is, in addition available in 135 and
120 formats.

Otherwise, as far as permanent retention of these images in
conservation reports is concerned, all these films are on a version
of cellulose acetate, which is considered, by many, to be an
impermanent support, thus to move to polyester support for a number
of films. The Kodachrome image may outlast its support. Cold, dry
storage as per frost free refrigeration (Wilhelm 1993) may be a
solution.

I think some conservation recording images should remain on
conventional direct to film media, where any question of image
manipulation of before or after treatment photos may arise. The vast
majority of process and progress photographs, however,  are better
stored as image files in more than one location, preferably as raw
or uncompressed files, but many institutions use JPEGs to save
system space.

James Elwing
Conservator, Archives,
Powerhouse Museum,
PO Box K436, Haymarket, NSW1238
Sydney, Australia


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                  Conservation DistList Instance 18:39
                 Distributed: Friday, February 18, 2005
                       Message Id: cdl-18-39-012
                                  ***