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For the third edition, I am seriously
considering including 1,000 or more color images on a DVD,
in addition to black and white images in the printed book.
All images will come from contributions from collectors and dealers.
I can be flexible for images that will appear in print.
However, images that will appear in electronic form must be of
higher quality. Here are the general requirements:
- Scan against a white background.
- Scan at 150-200 pixels/inch at full scale. (79 pixels/cm)
- Scan in pieces if necessary.
- (Always scan pieces with the same orientation.)
- Scan fronts only.
- Do not scan coupons or backs.
Yes, scanning IS confusing and it IS hard to get
reliably good images. Learn much more about the process and pick up hints starting with Scanning Certificates.
Trick 1. Turn off automatic sharpening.
When scanners use automatic "sharpening", the software tries to
increase the contrast along the edges of light or dark areas. Unfortunately,
fine lines in vignettes and borders confuse the software. The software
cannot clearly define the "edges" of very fine lines.
Certificates often become oversharpened, and consequently, become
unusable. Overly sharpened vignettes end up looking "sparkly"
and lack fine details.
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Oversharpened. Notice the "sparkly"
appearance, especially in the title.
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Trick 2. Turn off automatic color adjustments.
In a similar manner, colored borders confuse the automatic color
balancing of entry-level scanner software.
Trick 3. Turn off automatic exposure.
In my estimation, the worst thing is to let scanners set exposures
automatically. Certificates usually end up looking too dark or too light.
Scanners set exposure by looking for a continuous gradation between
black and white, or between colors and white. Certificates do NOT
have gradational tones. They are either black, white, or have fine
lines of solid color. Many scanners have a hard time setting good
exposure with certificates. So why bother?
Trick 4. If scanning large large certificates in pieces, do
NOT change orientation.
Certificates are normally too large for ordinary, letter-size scanners.
Nonetheless, you can use your scanner to get images.
- Scan large certificates in pieces and send the pieces.
- Do NOT try to patch them together.
- Use the same orientation for all pieces.
Here's why.
The light bulb on most scanners is in front of the sensors that measure reflected light. Imagine
that you scan your first piece with the top of the certificate facing
the back of the scanner. The sensors would read color as if the light
were coming from the bottom of your certificate.
If you flipped your certificate around to scan the remainder, then
it would be like the light was hitting the top of the certificate.
In other words, by flipping your certificate around, you make your
sensors see a completely different quality of light. In doing so,
you get different exposures and different colors.
Here is what happens when you change the orientation, and then
patch the pieces back together.
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This is an image from eBay. The bottom half of this bond was obviously scanned
with a different orientation than the top.
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Trick 5. Scan documents at full scale.
- Scan documents at full scale.
- Do not allow your scanner to reduce sizes.
There are two reasons for this.
When you allow your scanner to make reductions, IT makes decisions
about what information to discard. It reads information from several
surrounding points, mathematically averages information, and creates
new pixels that are not really there. The process is called "resampling."
Unfortunately, the software that comes with scanners thinks
it is working with average kinds of documents. Certificates are
not average documents. I have a special page that illustrates the problem of reducing certificates during scanning.
Trick 6. Scan against a WHITE background.
Certificates are not opaque. The color of the background ALWAYS
shows through. Colored backgrounds are the worst, but black is almost
as bad. Scan your certificates against a white surface.
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