regards digital storage

[Godfrey DiGiorgi <ramarren@apple.com>]

There seems to be a couple of minor things lacking in this discussion of
archival images through digital storage means.

1) No scan or CCD generated image is of the quality that an original 35mm
negative or transparency is at the present date. The picture elements 
(pixels)
of a piece of 35mm film is orders of magnitude greater than the best 
scanning 
equipment can achieve right now (2750-3600dpi seems to be the maximum of 
available equipment). 

It seems to me that we're really getting into some limits here. The 
competing constraints are 
 - the resolution of the lens
 - the resolution of the film
 - the quality of an individual image
 - the resolution of the scanner optics
 - the resolution of the scanner mechanism
 - the quantization noise generated by the capturing of 
   a real-valued, analog media into a discrete valued media
   with regard to bandwidth, etc.

2) That said, there is an odd fallacy in stating that CDROM stored images
will only last 20 years because the media will only last that long, if 
that
long. First off, since the information stored on a CDROM is purely a 
string
of numbers, as long as the media's ability to return the numbers is 
there, 
you can create exact duplicates of treasured images stored thereon with 
no generational degradation like would happen with any analog copy 
process.
So what if the media lasts 20 years, or even 3? You can duplicate it long
before it becomes unreadable and store a perfect copy of your scanned 
image
through eternity by digitally copying it every three years. Secondly, 
since
CD ROM and writeable CD ROM media has only been in existence a maximum of 
about 10 years or so, while 3M and other media producers have stated that
the expected archival permanence of the media is 20 years, there's really 
no proof that it's that long or much longer or shorter. I have Audio CDs
which date back about 11 years now, which have been played many hundreds 
of times, and I cannot on an oscilliscope determine any signal 
degradation. Again, it's just numbers and if the numbers are retrieveable,
they signal is able to be duplication without degradation.

With the above in mind, my own thoughts on this archival business are 
ambivalent. Very few images in photography are anything but transient 
slices
of reality, expressions of a moment in time captured through the vision of
an artist. Few of them have deathless collectibity. The fact that some 
very 
few do and can be deemed 'collectible', well, the fact that they have a 
lifespan is to the benefit of a collector as they become more valuable 
over
time due to scarcity. Nearly all will outlive the artist, in one form or 
another, with proper care. Even family pictures which are so precious to 
you
and your children and even your grandchildren become somewhat meaningless
after a third generation passes them on ... unless your name happens to be
Einstein or Rockefeller or Kennedy or something. 

I'm more and more moving my photographic processes into the digital domain
because they're easier for me to work with given a limited budget and 
limited facilities that way. I still do B&W printing, rarely, but mostly 
I just develop negatives and have them mastered to CDROM. Soon I'll have
my own film scanner and will put together a photo collection that I'll 
actually be able to utilize and show easily when people ask. But whether
it outlasts me by any substantial fraction of years is questionable in
its relevance. 

The fact that color is transitory is nothing new. How many realize that 
those 
gloriously 
pure white buildings of the Greeks and Romans were gaudily painted in the
colors of their day? Perhaps I'll work on that new machine
to convert my B&W images to cut granite or alabaster in bas relief and 
achieve a measure of immortality otherwise unapproachable by any other 
current photographic media... ]'-)

Godfrey