Collectible Stocks and Bonds from North American Railroads     by Terry Cox

A guidebook and catalog of prices
(I do NOT buy or sell certificates on this website)

Search this website for information about collecting stocks and bonds.


Search the Coxrail database for descriptions of 23,700+ certificates from over 7,400 North American railroad companies.


Contrast is the difference between light and dark. Photoshop and other expensive image manipulation programs allow 'non-linear' adjustments in contrast. In other words, they allow users to adjust the contrast of different parts of the spectrum differently. Photoshop professionals can perform near-magic when improving images by adjusting contrast.

But, let's be honest. Average users will settle for entry level equipment with dedicated software incapable of such fine adjustments. Almost all those programs allow adjustment in contrast, but the adjustment will likely be linear. In other words, the lights will get lighter in the same proportion as the darks get darker.

Professionals hate such minimal adjustment capabilities. I suggest realism. Average users have average needs and don't need over-the-top programs. I think average viewers are less picky about images than professionals realize. With deference to the pros, I will suggest that average users can improve the appearances of their certificate scans by judicious adjustments to brightness and contrast and little else.

Example of adjustments to a certificate using nothing but contrast. .

Piece of a certificate straight out of the scanner. Lowered contrast decreases the brightness of the border and the paper. Since the paper is less bright, the printing on the back appears more prominent. Unfortunately, the paper now looks more gray than off-white.
Increased contrast makes the lights lighter and the darks darker. The paper is now closer to its real appearance. The border is nice and bright, although possibly a little too bright. The back printing is not as noticeable. Contrast over-done. The border is artificially bright and the paper is too white and lacks texture and character.

Certificates are documents with naturally strong contrast between paper and very narrow engraved letters. Vignettes are not grayscale or haltone images, but interlocking patterns of very narrow lines interspersed with light areas of paper. Scanners, on the other hand, are generally set to interpret certificates as ordinary documents or photographs. As a consequence, many certificates appear too dark with less than realistic contrast. Here is an example of a typical scan (top) and the same image altered by a simple increase in contrast (bottom). Which image do you think looks better?

If you plan on scanning your certificate collection, be sure you experiment with simple adjustments in brightness and contrast before getting more exotic. I think you will like the results.

Back to Scanning home page

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(Last updated July 17, 2011)


I strongly recommend buying the Cox Catalog 3rd Edition from your favorite SCRIPOPHILY DEALER. Catalog cover
If they do not carry, or are out of stock, you may buy directly from me. Simply click the buy button below.



Papermental logoHelp support this free site! Please visit my eBay store called Papermental by Terry Cox. My inventory includes railroad passes, railroad ephemera, newspapers, magazines, engravings, and all sorts of paper collectibles.

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