preserving / ressurecting old docs?

From: David Gesswein <>
Date: Fri Jun 22 22:20:44 2001

From: Bill Bradford <>
>I'm scanning them in as 100dpi grayscale GIFs, then I will convert to
>other format(s) and eventually to PDF. Scanning directly to PDF with
>HP's software produces horrible output with compression artifacts.

I would really recommend higher resolution. 100 DPI is the lowest
resolution fax quality. Being grey scale will help readability on
the screen but printing probably won't work well on most printers.

I recommend 300 DPI black and white (line art) minimum for most of the
pages. For the pictures a grey scale scan makes the pictures better and if
you have software which allows mixing them that would work well and
allow for the smallest file size. The black and white compress well when
you use group 4 tiff. PDF also supports that compression format which
is how I do the on the fly conversion to PDF on my site, it just adds
PDF wrapper to the tiff. For smallest size the tiff should be singe
strip. You will need to adjust the threshold setting for best results.
Also when you are looking at artifacts from grey scale scanning view at
1:1 scale so you aren't seeing the artifacts from the rescaling to
screen resolution. It can make it look much worse than the scanned
artifacts from the screen printing actually are.

Since what I am using doesn't allow mixing I have just been doing the
black and white scans and seperatly storing grey scale scans for future.
I have also switched to doing the scans at 600 DPI for best quality and
making 300 DPI copies available for people with slower links. Hopefully
these will be around to when the size doesn't matter.

I did the cut the pages out of the binding for the handbook I scanned
since it was falling apart. I have found that I can't get good scans
on my scanner otherwise since the pages are still too bent so the scans
are warped.

I know that this is a lot of personal preferences and their isn't one
best way. Email me if you wish any more information on how I have been

My scans (and other peoples)
Received on Fri Jun 22 2001 - 22:20:44 BST

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