Timothy:

Thank you very much for the info!  This is the kind of info I have been
hoping someone could provide for us!  Let us know if you come across any
other info you think we may need :)

Sincerely,
  Ginger M. Young (email: [log in to unmask])
-----Original Message-----
From: Timothy Vitale <[log in to unmask]>
Newsgroups: bit.listserv.museum-l
To: [log in to unmask] <[log in to unmask]>
Date: Thursday, July 23, 1998 12:56 PM
Subject: Re: Gary Vine (scanning)


>I'm doing research on this subject, but have already missed one
>publication deadline.  Preliminary evaluation of skimpy data suggests
>some preliminary results.  I measured two scanners and the intensify of
>their cold cathode lamps (newer scanners).  Each put out about 2000 lux
>for 10 seconds on a one inch band; duration depends on resolution.  At
>600 dpi, on these scanners, that would be about 6 lux per hour.  The
>standard preservation recommendation for paper is 50 (to 150) lux light
>levels, for 12 hrs per day, 6 days a week for three months (4.2 weeks),
>every 3-5 years or 45,360 lux/hrs (calculated with 50 lux) exposure over
>every 5 years for its lifetime (which is usually estimated as 100-500
>years).  Six lux hours doesn't even register on the "lifetime meter".  I
>haven't measured heat, but it is also insignificant for the two SOHO
>scanners tested (both 1200 X 600 dpi 30/36 bit, flatbeds) from different
>manufacturer.  I haven't measured UV output.  I expect it to be present,
>possibly high, but also insignificant because of duration.
>
>Timothy Vitale
>Paper and Photography Conservator
>& Preservation Consultant
>Conservation Associates
>Aptos, CA
>831-684-2731 (another area code change in Silicon Valley)
>