On Sat, 30 Jun 2001, Davison, Lee wrote:
> > Scanning printed material much above 150dpi
is usually a waste
> > as most printing is done at about 70dpi.
What am I not understanding here?
70dpi with 80 characters per line and 66 lines per page would be about 7
by 9 pixels per character. That is reasonably average dot matrix printout
quality for the 70s, NOT suitable for manuals.
Even small outfits paid for typesetting at more than an order of magnitude
better resolution than that.
From the mid 80s on, when laser printers were readily
available, there was
a DECLINE in manual quality due to the use of 300dpi laser
printers
instead of typesetting.
We're talking old manuals here. Remember? OLD
manuals.
How old?
Nobody, commercially, makes books on laserprinters.
True. I made a master on a laserprinter, and had commercial xerographic
copies made from that. (cheaper by a substantial margin than printing
each one out on the laser printer) Then sheared them to size and bound
them in house. Anyone without a commercial grade paper shear (hint: that
is not a swinging arm, nor a pizza cutter) is not serious about producing
their own manuals.
If you can
manage it, i would say scan at 600 Dpi.
Waste of time, effort and storage space.
scanning at 1/2 the target printer resolution is
probably
the best you can hope for.
Scanning at just over twice the source resolution is
the best you
will ever get. More than that's a waste.
How is your OCR doing? THAT might be a better measure for whether what
you are doing is working.
--
Grumpy Ol' Fred cisin(a)xenosoft.com