Message-Id: <199701152157.PAA14015@library.wustl.edu> Date: Wed, 15 Jan 1997 16:47:51 -0500 From: Maria Daniels <mailto:maria@PERSEUS.TUFTS.EDU> Subject: Pink slides To: mailto:IMAGELIB@LISTSERV.ARIZONA.EDU
Paul Hillier wrote: >We have been given some slides for inclusion in our slide collection and
>they appear to have a pink colour cast. We don't know the age of the slides
>or how they have been stored.
>Is this the start of the breakdown of the slides and is it worth will
>keeping them?
Dear Paul, I've seen a bunch of these too, from the old Archaeological Institute of America archives. The pink cast is the result of some color dyes fading faster than others in the film. Over time, especially if the slides are projected or left out on light tables or under fluorescent lights, and if they are not stored in a dark, temperature- and humidity-controlled place, the dyes will fade at an uneven rate, giving the slides a "cast." C'est la vie! Yellow dye is the least stable in Kodachrome and Ektachrome films, even under dark storage conditions, so you will not infrequently come across slides with a cyan or magenta cast.
Kodak predicts image stability for all its slide films under dark storage, fluorescent illumination, and tungsten-halogen multiple projection conditions, and there are technical reference brochures you can order from their customer service center. The ones I have are E-105 and E-106, Image Stability Data for Kodachrome and Ektachrome Films. You may also find some information on their Web site, if you have Web access, at http://www.kodak.com. I'm sure the other manufacturers must have similar technical product information.
Is it worth keeping them? Well, if you don't have other slides of the same things, and if you have space, you may as well keep them. If you are scanning the collection, you can perform color correction on the slides in an application like Photoshop, and approximate "truer" colors for the pink slides.
Maria Daniels Perseus Project