Message-Id: <mailto:199503210422.WAA24843@library.wustl.edu> Date: Mon, 20 Mar 1995 15:36:32 -0800 From: Washington State Archives <mailto:wa-archv@WLN.COM> Subject: Re: Microfilm Digitization To: Multiple recipients of list IMAGELIB
I am curious, some imaging systems use COM as the "archival" or long term storage copy. When you say basic standards do you mean type of film stock and method of processing, or image quality (resolution)? Thank you.Mike Betz Washington State Archives mailto:<mailto:wa-archv@wln.com>
On Mon, 20 Mar 1995, Lee Dirks wrote:
> Message:
> > I'm curious why you don't just SCAN the source material using a 8
> > bit scanner giving you 256 gray level steps, and then make raster
> > com for the archive?
>
> Because COM does not meet even the basic standards for preservation
> quality microfilm, specifically the RLG Guidelines for preservation
> microfilm. Our greatest concern is the longevity of the master
> negative, when -- if properly processed and stored -- should last at
> least 500 years. COM does not have that lifespan or quality. Nor
> do digital scans of the same images. As Rothenberg states in his
> January 1995 Scientific American article, "It is only slightly
> facetious to say that digital information lasts forever--or five
> years, whichever comes first."
> -Lee Dirks (Preservation Resources, Bethlehem, PA (800) 773-7222)
>