Steve, My scientific studies went like this: Test No. 1. Keep Ektachrome slides in damp basements, blazing hot/freezing cold attics and garages for forty years. Keep Kodachrome slides in same conditions for even longer. Kodachrome slides look just fine. One of me when I was only two years old - and I'm OLD geezer now - will print correctly with no blemishes. Ektachrome slides are laced with fungus like a petri dish. Maybe good sour-dough bread starter but not much else. Test No. 2. Many rolls of dad's 35mm, Agfa film from WWII coiled like a spring for thirty-five years and then flattened out and stored between pages in heavy art books. Still look OK except they curve width-wise. Test No. 3 Wrap C.1900, 4 x 5 glass plate negatives inside newspaper for seventy years. Pictures are a bit faded but printable. The newspapers are yellow and a bit flaky but fully readable. AZ Build a 120/35mm Lookaround! The Lookaround E-Book 5ed. NOW SHIPPING http://www.panoramacamera.us > -------- Original Message -------- > Subject: [SPAM] [Fwd: Photography Half-Life (Decay Rate) Changes] > From: steve harris <dshlaw@xxxxxxxxxxxxx> > Date: Thu, June 25, 2009 12:11 pm > To: List for Photo/Imaging Educators - Professionals - Students > <photoforum@xxxxxxxxxxxxxxxxxx> > According to wikipedia at: > http://en.wikipedia.org/wiki/Half-life > The concept of half-life is often used to describe the decay of discrete > entities, such as radioactive atoms. It is the time when the /expected > value <http://en.wikipedia.org/wiki/Expected_value>/ of the number of > entities that have decayed is equal to half the original number. > The question is -- Has anyone on this list, or otherwise, done any > studies on the half life of photographic images recorded on various media? > The "decay" or loss of any given image could be from a number of causes > -- decay of the recording material, destruction due to damage from fire, > water, etc., discard by owner, change in technologies, etc. > Do the members on this list think that the half-live of photo images has > significantly shortened, because of the shift to digital? What about > different categories of images (professional vs consumer)? > Should a criteria of technology be the lengthening, rather than the > shortening of photo image half-life? > Is there anyone working on this issue with a mathematical or statistical > model?
