Message-Id: <199609040223.VAA27208@library.wustl.edu> Date: Tue, 3 Sep 1996 19:19:01 PDT From: Ricky Erway <mailto:BL.RLE@RLG.ORG> Subject: Re: Scanning Microfilm To: Multiple recipients of list IMAGELIB
REPLY TO 08/30/96 11:20 FROM mailto:IMAGELIB@LISTSERV.ARIZONA.EDU "IMAGELIB": Re: Scanning MicrofilmGeoffrey (and Bob),
I believe that the Minolta MS3000 is one of the film scanners that captures from the display screen. While this approach gets around the need to capture at a really high resolution to result in the equivalent of 300 dpi, the results of scanning from the display seem to be deficient as compared to those scanned directly from the film.
The scanners most often mentioned in scanning from microfilm are the Mekel (Amitech, in Fairfax, Virginia (703) 698-5057, is the (or a) distributor) and the SunRise mentioned earlier. These are both desk-top devices. I believe they can deliver an effective resolution of 400 dpi on an 8.5 x 11 original. Mekel, at least, now has a grayscale option for the M500 film scanner. There are others, both bigger in footprint and in price, that are more often used by service bureaus.
I agree with the previous post - try before you buy and don't settle for sample scans. You need to see it operate to be sure of what you are buying into. In no other area have I seen so many vendors say, "no problem, our machine can give you what you need" and then have many problems before giving up on proving it.
On the topic of resolution, the advice from the field appears to be worry at the low-end, but don't pay too much for the high-end. For a typical page at a typical reduction ratio (typical is a weasel word that I hope will help to deflect any criticism), around a 3000 pixel array is just adequate. Much less is unacceptable, a lot more, say over 8,000 pixel array, might be undetectable (depending on the nature of the original and of the film). Film scanner vendors are inconsistent as to whether they give the scanner's resolution relative to the film or to the original. The good news is that you've already got a preservation copy of the newspapers (the microfilm), so a legible digital image might suffice for your purposes.
Service bureaus are now offering prices of under .25 per image, but often when all the requirements (logging, filenaming, indexing, header info, derivative images, etc) are known, they creep back up toward the dollar mark. And film of newspapers is among the hardest (large size and small print).
One thing everyone seems to agree on is that the prime indicator for success is not whether you scan inhouse or outsource and not what equipment is used, but rather the quality of the film. The nature of the film is also a factor in cost. Is it 35mm? negative or positive? high contrast or continuous tone? sprocketed? blipped? of consistent reduction ratio? consistent page orientation? can the frame edges be automatically detected? do you want all the frames or selected frames? are the images skewed? will cropping be required?
The recently released Cornell publication, "Digital Imaging for Libraries and Archives," by Anne R Kenney and Stephen Chapman, is a treasure trove of information that may help answer some of the questions and help make sure you make an informed decision.
Ricky
____________________________________________ Ricky Erway -- mailto:bl.rle@rlg.org Member Services Officer, Digital Initiatives The Research Libraries Group 1200 Villa Street Mountain View, CA 94041-1100 (415) 691-2228 Fax: (415) 964-0943 RLG's Web - http://www.rlg.org/ --------------------------------------------
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