Message-Id: <199609032231.RAA18892@library.wustl.edu> Date: Tue, 3 Sep 1996 18:17:23 -0400 From: "Wagner,Lynn" <mailto:wagnerl@OCLC.ORG> Subject: Microfilm Scanning To: Multiple recipients of list IMAGELIB
One 8/30 Geoffrey Cannon mailto:geoff.cannon@sheridanc.on.ca wrote: >>As part of an ongoing project to digitize historic documents in Halton
>>County we have come to the point where we would like to take our historic
>>newspapers on microfilm and make them available on our Web site. We would
>>like to buy equipment and do it in house rather than out source the
project. >>Here are my questions:
>>1. Is 2000 dpi uninterpolated adequate for scanning microfilm?
>>2. Is there a scanner that can handle 100ft roll of microfilm without
being "customized"?>>3. I have just seen a brochure for a Microtek ScanMaker 35t plus that
will do 1950 dpi uninterpolated. Any comments about their products.The problem with scanning any microfilm is that since the image has already been reduced on film, you need an even higher dpi to achieve a reasonable effective resolution in terms of the orginal image. For example, if the newspapers were filmed at 16x, the 2000 dpi uninterpolated becomes 125 dpi relative to the original material. This may not be adequate. 300 dpi relative to the original would be preferred.
Also with newspapers, the number of pictures and the condition of the newspaper filmed may warrant grayscale scanning. Be prepared for larger files sizes. In addition to buying equipment, try to plan for indexing, how people will view (and navigate around) large images, etc.
I'd suggest you test the type scanning you wish to do on any type of equipment you are investigating. Also, inventory your newspaper collection. With all microfilm scanning the quality of the orginal is dependent on the quality of the film (it would be best to scan from print masters, know the reduction ratio, etc)
Lynn Wagner mailto:wagerl@oclc.org Preservation Resources Bethlehem PA http://www.oclc.org/presres/