23 Jul
2019
23 Jul
'19
5:30 p.m.
On Jul 21, 2019, at 12:16 PM, Jon Elson via cctalk
<cctalk at classiccmp.org> wrote:
On 07/21/2019 05:16 AM, Joseph S. Barrera III via cctalk wrote:
Another example that might call for higher than normal resolution is oddball text, where
subtle distinctions need to be visible. An example of this can be found in the scans in
the Knuth archive of the THE operating system sources. Those are line printer listings
printed with a typical medium-worn ribbon -- that's bad enough. But the printer is
upper case only printing mixed-case source material. That was handled in that OS by
overprinting upper case letters with periods. In a clean original printout that's
easy enough to see, but the scans seem to be about 300 dpi and with that the overprints
are often not easy to see. Since the source text is case sensitive this can be a
problem...
paul
What dpi qualifies as not "crappy"?
300dpi? 400? 600?
Most of the text of these documents don't need super high resolution. But,
some contain hand-drawn schematics where an 11 x 17 original has been shrunk to 8.5 x
11" and hand-written signal labels and part types are VERY small. These need to be
scanned at high resolution, with several retries while adjusting the image threshold to
make things readable.