Birding Optics

Joe Meche is a member of the board of directors of the North Cascades Audubon Society and is in his ninth year as editor of the chapter newsletter. Joe is also a member of the board of directors of the Washington Brant Foundation. He has been photographing birds and landscapes for over 30 years and has been watching birds for more than 50 years.

When it comes to watching birds, a couple of questions get tossed around almost as frequently as questions about winter gulls: Which binoculars should I buy? Do I need a scope? Well, one thing for sure, better binoculars and/or a scope won’t necessarily make you a better birder, in the same way that a Steinway won’t necessarily make you sound like Glenn Gould. However, better binoculars and a decent scope just might make your time in the field more enjoyable and make you a little less eye- and arm-weary at the end of the day.

Let’s have a look at binoculars (a.k.a., bins/binocs), first, since they are an essential part of our costume du jour. Perhaps the best way to begin is to decide how much you want to spend. If money’s no object, then skip this paragraph. If, however, you’re like the majority of us, you might want to shop around and make your sure that your initial considerations are within your price range. Without getting too philosophical, just remember that you should always be happy with your own binoculars and not drool over someone else’s Zeissleicaswarovskis!

When I was growing up, I borrowed or shared binoculars and didn’t have my own until I was a sophomore in high school. With the relative wealth that came from an after-school-and-Saturdays job, I marched down to the local Army-Navy surplus store and paid ten bucks for my first binoculars. I don’t even remember the brand, but they came with a case and were within my price range, given that my take-home pay was a hard-earned $12 a week! Those were great binoculars and the thing that I liked best was that they were mine! I no longer had to share with the kid down the street just so I could have an occasional close-up glimpse of a painted bunting. Life was good.

The same binoculars that I could have bought back then for $200 would probably break the bank today. But, to cite that familiar refrain, that was then and this is now. Clothing, food and shelter were provided by my parents, and that’s the only reason I could afford those $10 binoculars. To summarize the first consideration when buying binoculars—buy the best that you can afford.

After you juggle the issue of expense, you then decide what to do with those numbers that might be a little confusing at first but make sense after a short primer. The following binocular numbers all follow the same pattern—7X35, 7X42 and 8X42. The first number is the magnification and the second number is the diameter of the objective lenses, or the lenses that are farthest from your eyes—if you have them oriented properly, that is. Some folks steadfastly claim that 7X means that the bird is seven times closer, but folks, the bird doesn’t get any closer—the image of the bid is magnified seven times. So much for that popular misconception!

Addressing the first number, the majority of popular binoculars have magnifications that range between 7X and 10X. Initially, you might leap for the 10X to have a larger image to view; however, your field of view decreases as the magnification increases. If you look through a zoom telephoto lens, you’ll see this dramatically demonstrated as you zoom from, say, 28 to 400 millimeters. What this means is that you will find it easier to locate a ruby-crowned kinglet with a wider field of view.

Your selection of the proper magnification has other interesting factors to consider. Depending on the size of the objective lenses, the 10X binoculars might tend to weigh more and make them more difficult to use for extended periods of time. Heavy binocs will leave you arm-weary at the end of the day. The extra time you spend chasing those smaller birds will take its toll. Even with smaller objective lenses, it still takes more effort to steady a 10X image. All things considered, I am personally addicted to 7X for general, all-purpose binoculars.

The second number has a direct correlation to the amount of light that reaches your eyes. This number, divided by the first number, translates into what is alternately referred to as exit pupil, relative light index, brightness factor, etc. Early morning and late evening birding almost dictate that you choose binoculars that are brighter so, for the sake of this conversation, let’s refer to the brightness factor (BF).

I have binoculars that range in magnification from 7X to 20X. The 7X42s yield a BF of 6 while the 20X80s yield a BF of only 4. My 7X50s have a BF of 7.1 but the increased weight makes them a third choice for the field. Keep in mind that the same weight that you’re holding up to your eyes to see birds, will be hanging from your neck all day. Chiropractors everywhere are familiar with birder’s neck and the adverse effects of heavy binocs. By the way, the 20X80s must be tripod-mounted, unless you have—or want to have—arms like Popeye.

Just like the clothes you wear, your binoculars need to be a comfortable fit. You want them to feel good around your neck and, more importantly, you want them to feel good in your hands. Quick, accurate focus is essential, especially when chasing warblers or other small birds through the trees and over hill and dale. Close-focus is a good feature but not as essential as a sharp, bright image.

When you think you’ve exhausted your search, you must make a decision between roof prism and porro prism binoculars. Roof prism binoculars resemble a pair of straight, parallel tubes, while the porro prisms have the more traditional, offset-tube configuration. The porro prism binoculars usually have a wider field of view, so this is another consideration. This decision will be a matter of choice and how the binoculars feel in your hands. All the manufacturers worth considering have both styles in many variations from which to choose.

If you wear glasses, you need to look for binoculars that have a minimum of 15mm of eye-relief. Fold-down eye cups allow you to keep your glasses on to get a good view. Some manufacturers now have binoculars equipped with eye cups that simply turn and lock in place to provide the necessary eye relief. This is yet another option to consider before buying.

After all your diligent research, you’ve found the binoculars of your dreams and can hardly imagine life without them. You’ve also found that you’d like a better look at those large flocks of American wigeons to see if you can locate a few of the Eurasian variety; or maybe you’re doing a swan survey and you’d like to be able to read a few collars. Now that you’re getting serious, you need to consider a scope!

Some of the same search criteria that you use to buy binoculars can be applied to scopes. After you’ve made your decision, however, there’s one additional piece of equipment that you cannot do without—a good tripod. A stable platform is essential for hassle-free scoping of the more distant targets. The best scope on the market is wasted if it’s mounted on a poor tripod. Again, buy the best that you can afford. Make sure that you choose a tripod that has smooth pan and tilt operations. And while you’re at it, pick up a window mount for the scope. Ask anyone who has one, and they’ll convince you to get one, as well.

Without a doubt, the optics available to birders today are better than ever. The myriad of manufacturers and models can be overwhelming, but if you’re planning to spend a few of those hard-earned dollars, it pays to shop around. Web sites abound for one-dimensional looks at practically every type of binoculars made, but nothing beats the hands-on inspection and feel of your next binoculars—before you buy them.

For a good look at just about all the binoculars, scopes, tripods and window mounts you’d ever want to see, and maybe to narrow your search, the Internet has innumerable sites to visit. One of my favorites is http://www.eagleoptics.com. When you’re ready to make that big purchase, pick a nice rainy day to sit back and compare the various types and brands. If you stick with the well-known names, you really can’t go wrong. Eagle Optics is in the business of selling optics and their Web site is very comprehensive. §