Message-Id: <199802061459.HAA19638@dns.ccit.arizona.edu> Date: Fri, 6 Feb 1998 09:49:02 -0500 From: "Wagner,Lynn" <mailto:wagnerl@OCLC.ORG> Subject: Re: RLG standards To: mailto:IMAGELIB@LISTSERV.ARIZONA.EDU
RLG guidelines for preservation microfilming call for skew no more than 10% off the horizontal or 9 degrees. Unfortunately there are no RLG standards for either equipment or digital images.Even with very sophisticated scanners, such as the SunRise scanner, the presence of high amounts of skew can sometimes affect edge detection in a batch mode (of scanning a whole reel for example).
With bitonal images, most skew can be corrected either at time of scan or as a post process. For grayscale images, dekewing is far from "painless"
Lynn Wagner Preservation Resources http://www.oclc.org/presres/
>----------
What are the RLG standards? I don't know if this is a factor of cost. We have a $25,000 Fujitsu 3099 and still get skew which we clean up painlessly during routine enhancement.Suggest you look at Anne Kenney's book on QC.
Emil Levine Head, INIS Clearinghouse UN/IAEA/INIS PO Box 100 Vienna Austria A1400 43-1-2060-22880/29882 fax mailto:e.levine@iaea.org
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>From: Mark Allan[SMTP:mailto:mallan@LIB.NMSU.EDU]
>Sent: Thursday, 05 February 1998 20:55
>To: mailto:IMAGELIB@LISTSERV.ARIZONA.EDU
>Subject: RLG standards
>
>I recently talked to a person who is not a subscriber to this list, but has
>some background in imaging technologies. He stated that most of the
>equipment out there does not meet RLG standards with regard to digitizing
>microfilm, particularly due to film skew. Is this currently the case, and
if >there is equipment conforming to said standards, is anybody willing to
float >me their favorite products? Also, on the low end of the price range, does
>Screen Scan conform to these standards?
>
>
>Mark A. Allan
>Reference/Social Science/Outreach Librarian
>New Mexico State University
mailto:>mallan@lib.nmsu.edu >