[vcf-midatlantic] Large format scanner
hjohnson at retrotechnology.info
Mon Oct 18 16:29:42 UTC 2021
> scanning 17 X 34 inch schematics and documents
> 1) take them to a copy shop
ask if they have any copyright restrictions. I've had occasions where a
copy shop said "we can't copy materials that have a copyright". They
won't tell you that, if they provide a self-serve copier. But I've seen
notices on the copiers that "prohibit" copying copyrighted materials.
And generally large-format scanners aren't available for public use.
Please don't give me a hard time about this. I am reporting a
experience, not asking for a lecture on the subject of copyright, nor
giving one. And it may be, this experience doesn't occur anymore, or
only at national-brand copy services.
> 1a) copy-service costs rather high
Ask for donations from people who will benefit. Some people reject this
idea outright, it seems like begging or pleading poverty, or some kind
of evil capitalism. No, no, and no. People who benefit, sometimes like
to show their support and gratitude. If this is wrong, why is gofundme
> 2) take a photo
It's hard to illuminate a document evenly. Keep in mind: a scanner moves
the same light across the entire document. It even self-adjusts for
uniformity. Scanners are very smart.
A digital camera will *highlight* any change in illumination. and it
needs to know the "color" (kind) of illumination (sun, cloud,
incandescent, etc.) If you use a single-source (a light bulb), it won't
work, parts of the document are different distances away. *Try it with a
You might wait for a lightly cloudy day - then the sunlight is diffused
uniformly. And set your camera for "cloudy" to get the color right. You
might have to use a longer exposure; that means you have to physically
mount the camera so it doesn't shake in your hands. And set your camera
for the largest-sized images. again, try it with a newspaper to see if
you can get away with this.
People today are so used to smart-phone cameras, many don't have the old
digital-camera experiences I'm talking about, like using natural light,
worrying about light-source color/temperature, etc. People who take lots
of photos, set up light-boxes and diffusers and all that stuff.
All that said: maybe some high-end smartphones & cameras can do some
"auto-stitch" thing or "panorama" thing, and get a big image, AND do so
at 300 DPI or better detail that documents need.
> 3) scan pieces and stitch together with software
This works reasonably well, if you are familiar with a image
application. I use an ancient version of Paint Shop Pro. I won't
describe the details (read the documentation) but it amounts to pasting
the cuts into same-pixel-size cutouts, and then moving the current paste
to overlap exactly the previous-cut's edge features. With practice it
works pretty well.
Regards, Herb Johnson
Herbert R. Johnson, New Jersey in the USA
http://www.retrotechnology.com OR .net
preserve, recover, restore 1970's computing
email: hjohnson AT retrotechnology DOT com
or try later herbjohnson AT comcast DOT net
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