I don't see a SC41MS.pdf on that page so
I have no idea of the scanning resolution
or the encoding.
SC41MS.pdf was an Emulex manual that probably wasn't
from moremanuals --apologies. To be fair it is a PDF
that
has been OCR'ed down to text, then recomposed as the
document it was. Probably beyond the scope of this
discussion. Here's another** example,
ENIAC press release (3 pages / 48 K)
http://americanhistory.si.edu/csr/comphist/pr1.pdf
although admittedly from people with a lot more time and
money on their hands.
I did notice that many of the moremanuals pages tend to
show a scanning line when the're first displayed, as if true
white is noisy in some way --it either is light grey or contains
significant dot content.
BTW thanks for doing all the work!
**a pretty spectacular example showing the alignment
problems of the original typewriter, etc. Parent page:
http://americanhistory.si.edu/csr/comphist
John A.