Simple science makes yellow stamps easy to see

By Janet Klug

Autumn officially arrived Sept. 23. The days are getting shorter, and buying some stamps to work with when winter sets in seemed like a good idea, so I ordered some.

When the stamps arrived, I did a cursory inspection, and much to my surprise, quite a few yellow stamps were included. They were intriguing, but I was reminded of the fact that it is very difficult to see a stamp design that is printed in yellow ink.

It isn’t a new discovery that yellow stamps are difficult to see; this has always been true. Frequently it is hard even to discern a yellow stamp’s country of origin. However, decades ago I purchased a dandy little set of three vinyl colored filters: blue, red and green. Each one is specifically useful depending on the color of the stamp you wish to inspect. These little vinyl filters have proved over time to be magical.

Figure 1 shows one of the yellow stamps I recently acquired. Part of a postmark is certainly visible, but there is not enough of the marking to help figure out where it came from. I pulled out the blue filter and used it to view the stamp. Abracadabra!

As shown in Figure 2, instantly, the yellow printing became visible. The words “Escuelas” at the top and “Centimos” at the bottom were strong hints that pointed to Venezuela. Plus, the image of Simon Bolivar, military and political hero of Venezuela, stands out enough to identify the stamp as Scott 60. The image is not great, but the blue filter helped significantly.

My next challenge was the stamp shown in Figure 3. This stamp is extraordinarily difficult to see because half of the stamp is covered with a heavily inked “killer” cancellation to keep the stamp from being reused. The yellow image is barely visible to the naked eye, but I decided to try scanning it.

Much to my surprise, the scanned image did improve the quality of the stamp’s visibility, but I still could not find the name of the issuing country.

Out came the blue filter again. The resulting image is shown in Figure 4. “Espana” (Spain) shows quite well at the bottom, as does the side view of the allegorical figure of Justice, both factors making the stamp easily identifiable as Scott 201.

Of the three yellow stamps shown with this article, the one in Figure 5 was the most difficult to identify, to deduce the issuing country and then the correct catalog number. The cross on the postmark offered a good hint, because that cross is a common symbol of Switzerland.

However, even knowing where the stamp probably came from didn’t make it easier to determine the image and catalog number. Once again, the blue filter came into play, and Figure 6 shows the resulting filtered image of a seated classical figure with a shield bearing the cross that is repeated in the postmark.

You can clearly see the country name “Helvetia” (Switzerland); the seated figure is Helvetia, a Swiss national symbol, and the denomination is 15 centimes. Together, these elements identify the stamp as being Switzerland Scott 54.

The red and green filters also have good uses. They don’t help much with the yellow stamps, but they can be of enormous assistance when trying to pull out a hard-to-read postmark or overprint. Figure 7 pictures an Australia King George V 1-penny red stamp with a postmark that is clear on the left side but very faint on the right side.

Eager to learn if I could read the rest of the postmark, I pulled out the red filter — red, because it would “magically” make the red printing disappear and only the black and gray postmark would be visible.

Figure 8 shows how the red filter revealed enough of the postmark to indicate mailing from Kangaroo Valley in N.S.W. (New South Wales) on May 6, 1918.

Unfortunately, it does not appear that my color filter kit is still manufactured. Checking online, I could not find any available from several dealers in stamp accessories.

However, I did find what is described as “a set of three primary and three secondary acetate filters” mounted in plastic frames, at a cost of $12.95, from Scientifics Direct.

These are not specifically made for stamp collectors, but the set looks like it would work for our purposes. Camera shops have colored glass filters for use on cameras that can be used effectively on stamps as well.

Today’s technology offers a lot of options for collectors who have access to a computer and the Internet. I found that taking a photo of a stamp with the camera on my cell phone automatically improved the stamp image, as did my printer’s scanner.

If you have a scanner, you can scan a stamp or other item and upload the image for free to RetroReveal, which is a project hosted by the University of Utah that is devoted to “revealing lost content in manuscripts, music, art, archaeology, and architecture.” It certainly will work for stamps and covers, too.

Once you have uploaded your image, RetroReveal will use various filters on it and show you the results, and you can select the one that best serves your purpose. Scanning the stamp and uploading it to RetroReveal took more time than using my vinyl filters, but the 32 different images provided by the website were fascinating. Some made the postmark go away completely, others made the background disappear and the postmark became crystal clear.

Figure 9 shows one of the filtered RetroReveal images of the yellow Switzerland pictured in Figure 5.

Using these handy tools, there is no second-guessing what image is on the yellow stamp or its issuing country. It’s science, but it’s also like magic.