This message contains 7 messages on the same topic. Moderator XXXXXXXXXXXXXXXXXXXXXXXXXXXX Message 1: Travis, We haven't had any problems with mylar interfering with scan quality. It is possible, however, that the there is a very very slight focus issue due to the thickness of the plastic. For our purposes, this has been undetectable. Matt Matthew A. Knutzen Assistant Chief, Map Division The Humanities and Social Sciences Library The New York Public Library 5th Avenue & 42nd Street, Room 117 New York, NY 10018-2788 [log in to unmask]; 212-930-0562; fax 212-930-0027 http://nypl.org/research/chss/map/map.html XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Message 2: Travis - All of our scanning is done through mylar and I do not believe you will notice any difference at all and, depending upon your scanner, the encapsulation may be safer for the original artifact. One minor disadvantage is that if the mylar should have a "kink" or scratch on it, your scanner may pick that up and scan it as a streak across your map. If you have a digital imaging group in the Library they should be able to configure your scanner for optimization using the mylar. David Cobb XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Message 3: Greetings. It is possible to scan encapsulated maps and have the scans turn out fine. As another poster mentioned, some possible concerns include focus and glare. The two immediate questions I would have are: what kind of scanner are you planning on using? and how big are the maps? For instance, on a flatbed scanner, as long as the entire item - film and map - is flat on the scanner, the scan should work fine. If even a small corner of the film is raised above the surface, you will probably end up with glare and/or streak marks. Interestingly enough, we scanned about 1500 encapsulated maps (out of 3500 total) as part of a 2-year project. You can see the maps at: http://dallaslibrary.org/CTX/murphyandbolanz/home.html (You will need the DjVu browser plugin (free) to view the maps). When we were planning for this project and deciding whether to encapsulate or scan first, we found that the polyester film (5 mil thickness) acted as a filter of sorts, cutting down on the harsh yellowing of the paper. The end result was we were able to read the pencil notations on the maps much easier if the maps were scanned after encapsulation. The Addition Book maps in this collection were scanned on a MicroTek Artix Scan 2020. Most of the Block maps were scanned before encapsulation, but some were scanned after encapsulation using a planetary scanner, and the scans turned out just fine. Good luck with your project. Cheers, Michael C. Miller Special Collections Librarian Dallas Public Library, Texas/Dallas History & Archives Division 1515 Young St. Dallas TX 75201 214-670-1440 fax: 214-670-1437 [log in to unmask] Visit us at http://dallaslibrary.org XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Message 4: Travis; There is nothing like a test... I have found that for material that is not heavily used, bonding two sides of the mylar capsule works and afte a scan, finish it off. Patrick McGlamery XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Message 5: It can cause glare and moire. - bri [log in to unmask] XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Message 6: Hey Travis, We scan using a Contex scanner whereby the sheet is fed into the front of the scanner. The biggest problem is as the sheet reaches the end, any air that might be in the mylar collects and wrecks that part of the scan. I suppose if you were using a flatbed this would not be a problem. Otherwise, in my opinion, the mylar itself doesn't detract significantly from the image quality. However, with time and use, the mylar can become cloudy from sliding on other surfaces which can lessen the scan quality. ___________________________ Chris Mixon Map Collection / GIS / Digital Resource Lab Auburn University Libraries 231 Mell St. Auburn University, AL 36849-5606 Phone: 334-844-1759 Fax: 334-844-1703 E-mail: [log in to unmask] http://www.lib.auburn.edu http://www.nacis.org XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Message 7: It has been my experience that there is no problem with scanning of encapsulated maps. The transparent sheet makes no effect on the quality of the scan, whether using a flatbed scanner or a large format continuous feed scanner. And with the latter type, the extra layers of the capsule do not seem to pose a problem for the rollers as the map feeds through. In fact, I think the mylar adds protection from mechanical damage that could occur without it, especially where an edge or corner might be caught as it feeds through. I must indicate that my experience is limited to only a small number of attempts at scanning of encapsulated items. A colleague with far greater experience and knowledge using scanners says that the encapsulation presents no problem for scanning, and my experience bears this out. Ken ___________________________ Ken Grabach <[log in to unmask]> Maps Librarian Phone: 513-529-1726 Miami University Libraries Oxford, Ohio 45056 USA XXXXXXXXXXXXXXXXXXXXXXEND END