I would agree with what both Mark and Bill have mentioned in terms of
archival images and future usefulness. However, the primary question (in my
mind) is what is useful now. Having a higher than screen resolution now
affords some additional return on investment on the longevity of the files
in that a "simple jpeg" now (bear in mind that file format and resolutions
have no correspondence; one can have a 300 dpi, for print jpeg or a 72 dpi,
for display TIFF) may not be sufficient in 18 months time where it is
conceivable that scanning at a somewhat high resolution may have utility for
3-4 years.
Another consideration is the utility of the files in contexts other than
display. OCR, for instance, can utilize the higher resolution to return
better results -- my experiences with OCR and 72 dpi for display images have
been rather poor whereas the higher (300 dpi) resolution images OCR much
better.
A final consideration is the actual effort of scanning. While larger file
sizes do require additional storage space and handling issues, much of the
actual effort involved in scanning is the initial image acquisition. By
using the highest useable resolution available in a non-lossy format, it
allows going back and converting the image for other purposes as things
evolve. A corollary to this is that many of these projects may be one-time
events from a funding standpoint and that using the equipment and resources
to their maximum advantage now is merely being judicious in the use of
resources.
Tim
--------
Tim Au Yeung
Manager of Digitization Initiatives
Information Resources (Press)
University of Calgary
voice: 403.220.8975
email: ytau (at) ucalgary.ca
----- Original Message -----
From: Mark Conrad <[log in to unmask]>
To: <[log in to unmask]>; <[log in to unmask]>
Sent: Monday, January 10, 2000 7:19 AM
Subject: Re: Greetings, and question on Scanned Images
>
>
> Just to amplify a little bit on what Bill has said... The problem is more
basic than scanning at higher resolutions at a later date. There is no such
thing as an archival digital image. If images are to be kept for more than a
few years they will have to migrated to new hardware and software as the
technology rapidly turns over or some other way of providing access to the
then-obsolete formats will have to be secured. The technology to read a
particular TIFF file may be around a little longer than most because of the
widespread use of TIFF, but it is highly unlikely that the technology to
read TIFF 4 or 6 images will be commonly available in 5-10 years.
>
> One possible way around this problem is to film the materials at the same
time that you scan them. Assuming the film is shot to produce an image with
a qi of 8, processed to archival specifications and stored under proper
environmental conditions, it will be around for 100 or more years. The film
could then be re-scanned at a later date to take advantage of the current
digital technology.
>
> Long-term preservation of and access to software-dependent objects is the
topic of a great deal of research right now. See for example:
>
> www.sdsc.edu/nara
>
> www.interpares.org
>
> info.wgbh.org/upf/
>
> Just my two cents from an archival point of view. These views are my own,
not necessarily my employer's.
>
> Mark Conrad
> Director for Technology Initiatives
> National Historical Publications and Records Commission (NHPRC)
> National Archives and Records Administration
> Room 111
> 700 Pennsylvania Avenue, NW,
> Washington, DC 20408-0001
> phone: 202-501-5600 ext. 233
> fax: 202-501-5601
> e-mail: [log in to unmask]
>
>
> >>> Bill Barrow <[log in to unmask]> 01/10/00 03:08AM >>>
>
> My concern here is that we are making "archival" TIF files at, say, 300
> dpi, when significantly more information than that is available on the
> original photographic print. I expect that all these digital archival
> files will need to be re-scanned someday soon, when hundred-gig files
> aren't a big deal to create, transport, store and use. I can wait, but
are
> the folks investing big sums of money creating these archival files today
> really aware that their work is only temporary? Are we encouraging
> expensive scanning projects when, for now, perhaps only a simple jpeg is
> necessary?
>
>
> >>At the Huntington Archive where we do almost excliusively images ranter
> >>that text documents, we have found the file size a particularly
difficult
> >>problesm which we are still discussing. Archival storage of images, has
> >>for us been at the maximum "usable" resolution, and not the maximum
> >>possible resolution. With scanners that go up to 14,000dpi and true
5,600
> >>dpi, hundred Gb files are possible but who wants all that data from a
> >>single sheet of paper or film?
>
> >If you have a large object and want high quality reproduction -
especially
> >of details - you have to go beyond 300dpi sometimes - and certainly file
> >sizes grow with object size...
>
> Bill Barrow
>
>
>
> * * * * * * * * * * * * * * * * * * * * *
> WILLIAM C. BARROW
> 13537 Cedar Road
> University Heights, OH 44118
> (216) 397-8327
> [log in to unmask]
> http://www.csuohio.edu/CUT/wcb2.htm
> - - - - - - - - - - - - - - - - - - - - -
> Special Collections Librarian
> Cleveland State University Library
> 1860 East 22nd St., #201
> Cleveland, OH 44114-4435
> (216) 687-6998 - office
> (216) 687-9380 - fax
> - - - - - - - - - - - - - - - - - - - - -
> THE CLEVELAND DIGITAL LIBRARY
> http://web.ulib.csuohio.edu/SpecColl/cdl/
> * * * * * * * * * * * * * * * * * * * * *
>
>
>
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|