Digitising collections of microfiche - Re: Looking for opinions...

[Shaun Halstead]

On Fri, Mar 30, 2018 at 9:17 AM, Toby Thain via cctalk <
cctalk at classiccmp.org> wrote:

> On 2018-03-30 9:21 AM, emanuel stiebler via cctalk wrote:
> > On 2018-03-29 14:50, Fred Cisin via cctalk wrote:
> >
> > Just as we talk about scanning hundreds of them. How do you guys clean
> > the fiche before scanning? Some of mine spent some life in garages,
> > boxes wherever, and definitely have dust & dirt on them ...
>

  It is virtually guaranteed that what you have are diazo duplicates.  This
is fairly easy to determine.  First, are they blue or translucent black in
color?  (Or, is there a colored stripe behind the title?)  Second, are both
sides of the film relatively shiny, or is one side obviously dull?  If both
sides have a shine to them, this is diazo film.  If one side is dull, is it
black, or colored?  If it's black, you have silver film, which may be
cleaned with 99% isopropyl alcohol and air dried.  If it has color to it,
but is dull, it's probably vesicular film, which should be carefully
cleaned the same as diazo film.

  I would exercise extreme caution when cleaning duplicate film.  Diazo
film is not as stable as silver film in the presence of solvents.
Distilled water is much safer, and is what we used on diazo in the lab.
Also, you don't want to wipe film (dry or wet), as diazo duplicates are
fairly easy to scratch.  Wash with water, air dry.  (Source: >20 years in
the microfilm industry.)

--Shaun