Don't be too quick to sell binoculars at a garage sale. They might be worth more than you think

You probably have a set or two laying around the house, maybe for birdwatching or football games. 

Some two million binoculars are sold each year in the U.S., most now made in Asia and not terribly expensive. However, binoculars with their rich history have become an increasingly popular category for collectors. Here are a few things to know:

First, let's review the lingo. A "binocular" is a single instrument while a "pair of binoculars" denotes two. Most people don't get this right, including me, but now we know.

Binoculars were first invented in France in the 1840s. They started small, primarily as opera glasses, but by the Civil War were being used in battle. These larger versions became known as field glasses. Although such instruments were often purchased privately by officers on both sides, a few were actually issued and carried either "U.S." or "C.S.A." (Confederate States of America) imprints. Those markings add substantial value.

Early versions were little more than two telescopes joined together. A series of lenses created magnification but the addition of prisms around 1900 made for a much better viewing experience. 

By World War I, binoculars were widely used although few had a magnification greater than 6x. Short and squat, Bausch & Lomb binoculars with brass prism covers and a distinctive orange leather covering are popular artifacts from that era. Their value is modest (usually around $100) but they were well-made and remain useful today.

And that's one of the most interesting things about binoculars. Unlike any other viewing instrument, basic binocular design has remain unchanged for 100 years. Indeed, many binoculars made during World War II — and there were dozens of varieties on both sides — are still considered today to be among the best you can buy. 

Other than optical coatings introduced during the war to aid light transmission and reduce reflection, there has been no other technological advancement of great significance for all that time. When you consider how much cameras, microscopes and other optical devices have changed, it's remarkable that binoculars have remained so much the same.

Moreover, unlike many other collectible categories, binoculars have great utility. They are useful in a thousand ways, and their portability and general ruggedness allows them to add value to almost any distant situation. If the sense of sight as an information-gathering tool is perhaps our most important one, something that serves to enhance that ability must be a good thing, right? Right.

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Anyway, back to the product itself. If there is a Holy Grail to binocular collectors, it is likely the 8x60 U-boat binoculars used by the German Kriegsmarine during World War II. Made by the two great German optical houses Leitz (Leica) and Zeiss, these large and heavy glasses provided an enormous advantage to German "Wolfpacks" (groupings of U-boats) during the early war in the Atlantic. Their field of view was dazzling and their clarity near edge to edge. Today, such binoculars are worth thousands of dollars and catnip to any serious collector.

On the American side, the U.S. Navy Mk 42 made by Sard was used for anti-submarine patrols and has gained a devoted following. Its 6x magnification was not particularly remarkable but the giant optical elements (both prisms and lenses) used in construction created a field of view that was simply extraordinary. For anyone putting one of these monsters up to their eyes for the first time, the response is invariably the same: "Wow!" There is simply nothing comparable made today, and good examples can still be found in the $600 to $800 range.

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In fact, most collector interest revolves around optics from World War II, both Allied and Axis. American glasses were made in a range of sizes and magnifications, all the way up to giant 20x120 pedestal-mounted units found on the bridges of battleships and destroyers. The British introduced all manner of binoculars, none with particularly fine optics but many with quirky designs.

Although most have disappeared into collections, some can still be found along London's Portobello Road and occasionally online. As precision instruments go, they can be quite reasonable, often less than the likely cost of reproducing them today. Counterfeits have not been a big problem in this category either, eliminating some of the usual hazards of collecting.

So, don't be too quick to put Grandpa's binoculars out at your next garage sale. They may be worth more than you think.

Mike Rivkin and his wife, Linda, are longtime residents of Rancho Mirage. For many years, he was an award-winning catalogue publisher and has authored seven books, along with countless articles. Now, he's the owner of Antique Galleries of Palm Springs. Want to send Mike a question about antiques? Drop him a line at info@silverfishpress.com.