Cut the rez on your scanner
to 100 pixels per inch and scan a page. If you can read it then that is
fine.
If not go up to 150 pixels per inch which is about the max size file
that I can publish for a 8.5 by 11 page. Send one page at a time to me as
my
20 gig hard drive will have no problems for years to come. After all I
don't
run bloated windows here :-)>
Paul Lamar
Paul, the resolution on my scanner is calibrated in dpi (dots per inch?) Is
that similar to pixels? And should I use 100 dpi by default to scan photos
for email? The default setting is 150 dpi on my AGFA SNAPSCAN 1212u scanner.
Yvon.
Yes. Same thing. The rez you can use and still have a small file
depends on the size of the illustration you are scanning. If I were scanning
something as small as 2 by 2 inches I would use 400 to 600
dots per inch. If 8.5 by 11 you would be limited to about
100 to 150 dots per inch.
Paul Lamar
Well, trying not to be anal about it, bu technically, resolution in
pixels normally refers to digital converted to analog computer screen
capabilities. DPI, or dots per inch, usually refer to scanners or
printer capabilities. Pixels refer to full screen usage. For example,
1024x768 resolution will be 1,024 (dots across) times 768 pixels (dots
down) = 786,432 elements of information, regardless whether the screen
is 3 inches or 36 inches. The picture remains the same and the total
size of the image stays the same.
Now, dpi is not like that at all. 100 dpi (squared is the norm, that is
y dots across by y dots down). Therefore, at 100 dpi a 3x5 scanned
picture will yield 3x100 times 5x100 = 150,000 elements of information.
Ignore color depth for the moment. At the same 100 dpi, an 8 1/2 x 11
inch picture scanned will require 8 1/2*100 * 11*100, or 935,000 pieces
of information. Ok, if you now assume 24 bit color, multiply each
number by 3 (8 bits per byte) to get the actual uncompressed size of the
files. 3x5 at 100 dpi in true color = 450,000 bytes. 8 1/2 x 11 in
true color = 2,805,000 bytes. Finally, an 8 1/2 x 11 image scanned and
saved in 300 bpi yields a file size of 25,245,000 bytes or 25 megabytes
roughly! Imagine sending that one page over someone's telephone
Internet connection. Shoot, even DSL or cable modem will choke a little
on each page at that size.
That is why the larger scanned images take so much more space to send
via email.
HTH (and you didn't get too bored),
AI Nut
You missed one thing. A jpg will compress this a lot.
You do have a very important point however.
It started with the Macintosh and went down hill from there.
Somebody decided it would be cute if they allowed bit mapped
fonts in word processors and other programs. This causes
Microshit Word for example to convert a 14K plain ASCII text file
and a few jpg's totaling about 350K into a .doc file over 20Meg!
The bit mapped fonts add absolutely nothing to the information
contained in the plain ASCII text file. All it does is line the pockets
of digital terrorist Bill "Osuma bin Laden" Gates with riches
way beyond anybody's wildest imagination.
This set world wide computer productivity back 20 years!
Ed Anderson just tried to send me that 20 meg file broken up in to
several multi megabyte pieces and it brought the mighty
earthlink.net to its knees. Not your fault Ed. How could you
have known? I had to call earthlink and have them abort the
process.
That bit mapped
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