Re: Damage to alt-photos by scanning

Wayde Allen (allen@boulder.nist.gov)
Thu, 12 Feb 1998 09:44:54 -0700 (MST)

On Thu, 12 Feb 1998, Sil Horwitz wrote:

> With new scanners, the light source is fluorescent which does not
> generate heat and there is only one pass for all colors, so the time
> required to make a scan is insignificant insofar as affecting any print.
> I am presently doing research on the stability of the various types of
> prints (but particularly those created with dyes, such as inkjet
> printers) which I hope to have ready by this summer. I had not considered
> scanners as the times and light outputs are so small.

I tend to agree about the time and intensity of the exposure. Basically,
viewing or handling any old print causes some degree of damage, so one
needs be reasonable about what constitutes "acceptible" use. People
making copy photographs outside in sunlight are almost certainly causing
much more wear and tear on the original than someone scanning.

On the other hand, fluorescent illumination tends to provide higher levels
of UV light. Is it a problem? I don't think we really have much data on
this. I think that a test similar to what I described in my previous post
would be reasonable to perform if for no other reason than to indicate
whether there is a problem here or not. I'll try to find the thread from
the photogenealogy list, and see if I saved the densitometer data that was
sent.

- Wayde
(wallen@boulder.nist.gov)