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Re: Apple II Reference Manual Addendum PDF now online



Paul Schlyter wrote:
In article <avXve.78228$HI.71270@edtnps84>, to.email.me@post.a.request.message says...


What I'm doing now is using a Canon generic LiDE scanner
with Paint Shop Pro 7.02, scanning at 300 dpi and then saving
as a JPG with "1" for compression, meaning minimum
compression.  Maybe there's something else I could do to
improve the quality?


Yes: never store the images as JPG when small detail is
important.  Instead choose a file format with non-destructive
compression, such as GIF, PNG or TIFF.  To cut down the size
of the image file as much as possible, instead try to minimize
the number of colors in the image.  These images are frequently
black-and-white, so scan them in as such - or convert the image
after the scan from "color" to "greyscale".  Next, cut down the
number of grey levels as much as possible.  16 grey levels usually
works fine here (each pixel will then only occupy 4 bits of data
in uncompressed form).  Even just 2 grey levels may work (i.e. just black
and white, no shades of gray) - if so, the size of the image is really minimized, since each pixel will then occupy only one single bit in
uncompressed form.  A 2 gray level b&w image, saved as a GIF file, can
be considerably smaller than a JPG file at the same resolution - this
may allow you to scan the image at still higher resolution, without
the GIF file getting larger than the JPG file at the original resolution.

I find that 300dpi GIF works very well for black and white originals.

I'd recommend using at least 4-8 gray levels for scanned images,
just to provide some anti-aliasing.  This often provides greater
benefit than increasing resolution.

-michael

8-voice music synthesizer using NadaNet networking!
Home page:  http://members.aol.com/MJMahon/