Message-Id: <199810062203.PAA28498@dns.ccit.arizona.edu> Date: Tue, 6 Oct 1998 14:19:18 -0700 From: James Otto <mailto:jotto@ROCKY.CLAREMONT.EDU> To: mailto:IMAGELIB@LISTSERV.ARIZONA.EDU
Hello David,We did this very thing with some old maps and charts. A graduate project to provide historical documents over the web needed to have scanned some fold-out charts of about 9 x 18 in. The age of the items and their layout vis a vis the scanner lid precluded us from even using the full imaging area of our scanner and thus we had to do as many as three scans of each chart to capture the entire thing. We used the same procedure in Photoshop that Rachel Murray described, with good results (though sometimes including the same shading variences she mentioned).
One important point is to carefully position the item for each scan so that there is minimal (if any) skew between sections. Fortunately Photoshop will let you rotate images by very small degrees, so quite a bit of precision can be achieved when matching up pieces. Still, the rotate-and-match process can involve quite a bit of trial and error and is best used only as fine-tuning. It's less time consuming to get things as straight as possible during the scanning process, but it's a nice feature when you need it.
Another nice feature of Photoshop is its ability to change the opacity of different sections as a guide in matching. First, when scanning I would make sure there is at least a little overlap between sections. Then, following Rachel's suggestions, I would: (1) create a blank canvas and place the first piece onto it; (2) place the second piece onto the canvas approximately where it should go; (3) change the second piece's opacity (to, I'd suggest, between 40 and 50%) by using the "layers" toolbox to make it semi-transparent; (4) move the now semi-transparent second piece over its matching edge on the (fully opaque) first piece until you see the details line up; (5) if the details match up, go to the layers toolbox and bring the second piece's opacity back up to 100%; (6) if the details don't match up, undo your paste of the second piece and fix any skew in the second piece that may be causing the mismatch, then repeat steps 2-4 again.
This may be more than you wanted to know right now, but this is a good (if not perfect) way to make sure pieces match up. Bottom line: it *is* possible to scan in sections and paste together later. Filming first, then scanning the prints, negatives, or transparencies is also an option if you make sure that the camera is close enough to the object and the film format allows sufficient resolution for your needs, and that you have the right scanning equipment to digitize film. Hope this helps.
James
David M. Jellema wrote:
> We are trying to figure out a way to post a large collection of (old)
> sheet music on the web. We have a scanner, but like most standard
> scanners it has an image window of 8.5" X 14" and invariably sheet
> music
> is a half inch or so wider.
>
> Has anyone had success with scanning two portions of the image into
> separate files and then, with software like Adobe Photoshop,
> 'splicing'
> them together? Is this approach unreasonable considering the time it
> might take to do a large number of oversize images with respectable
> results?
>
> Our other option might be to copy the image by camera onto 35 mm film
> and
> then run the film through a digital image processor/creator. While
> this
> might cut down some of the time lost in pasting images together, the
> image
> might lose clarity in the photo process.
>
> Is there anyone who has posted digital images larger than 8.5" X 14"
> to
> their web, and if so, how did you get the whole image?
>
> Any comments are welcome. Thank you.
>
> David Jellema
> Center for Popular Music
> Box 41
> Middle Tennessee State University
> Murfreesboro, TN 37132
> (615) 898-2449
> mailto:djellema@frank.mtsu.edu
> http://www.mtsu.edu/~ctrpopmu/
>
> Imagination is more important than knowledge.
>
> --Albert A. Einstein
-- James A. Otto Digital Projects Specialist and ERes Manager Honnold/Mudd Library Special Collections (The Libraries of The Claremont Colleges) 800 N. Dartmouth Avenue Claremont, CA 91711-3991(909) 607-7530 (x77530) (Phone) (909) 621-8681 (Fax) mailto:jotto@rocky.claremont.edu
"Through tower halls the Many come to talk, Lies twisted into truth, truth into lies; All come and go, and gossip never ends. Talk, talk, talk, talk fills many hundred ears That empty as a story's told, rehashed, And told to someone else, or fiction grows... Rumour takes in all things at sea, on land, And, at a distance, in the skies of heaven, Everything heard or seen throughout the Globe." --Ovid, Metamorphoses, Book 12