Tips For Buying Nature-Viewing Binoculars

by: Kurt Hagemeister

How to Select The Optimal Binoculars for Watching Nature in Your backyard and Out In The Field.

Many people who want to buy binoculars for watching birds and nature are bewildered by the variety of models available. Certainly, there are many fine binoculars on the market that are excellent for nature-viewing. But, what DOES define a good binocular for watching birds, animals, butterflies, and even reptiles? First, there is NO best binocular for any purpose. Every model of binocular has its pluses and minuses. Even an awesome top-of-the-line binocular from Leica or Swarovski has a disadvantage – price. They’re just too expensive for some people.

But, here are some tips on what to look for in your search for great nature-viewing binoculars:

Basic Specs – First, a brief definition of the basic specification for any binocular, e.g. 8 x 40, or 8 by 40, is in order. The first number is the magnification power of the binocular. It will make an object appear that many times larger than the naked eye. So, an 8 power binocular magnifies an image 8 times. The second number is the diameter of the larger, or “objective” lens in millimeters. This is the lens that gathers in the image of the object you’re looking at. So, an 8 by 40 binocular has a 40 millimeter objective lens. The larger this lens size, the larger the binocular body. This can be a factor if you can’t carry around something very heavy for several hours outside.

Compact vs. Full Size – Basically, binoculars with an objective lens smaller than 30 mm are considered “Compacts”, while ones with lenses larger than this are described as “Full Size”. In most cases, I recommend people to go with a full size binocular for watching birds and nature. One reason is that they are just a lot easier to look through. A reason for this is compact binoculars have correspondingly smaller exit pupil lenses (the smaller lenses you actually look through) that sometimes make it hard to see the whole field of view. Another reason is that full size binoculars are brighter when compared to a compact model of similar optical quality. This results in sharper, clearer images most of the time. So, look for binoculars in the 35 mm to 45 mm range. The only time compacts may be desirable is when traveling dictates carrying around the smallest possible binocular. Larger size lenses (50 mm or more) result in heavier, bulkier binoculars that may be harder to carry around. But, if you don’t mind the larger size, these larger lens binoculars can offer very good brightness and ease of use.

Magnification Power – This can often be a subject of debate among birdwatchers. Most hand-held binoculars are in the 7 to 12 power magnification range. 7 and 8 power are considered a general-use range because they usually have a larger field of view, which is the maximum angle a particular model of binocular can see. This is usually expressed as a number of feet in width that can be seen at a standard distance from the binocular (usually 1000 yards). A good range for field of view is 350 to 400 feet. Higher magnification binoculars (9 to 12) have relatively lower field of views – lower 300 feet range. But, if you’re mainly using them for birdwatching, this is not often a big problem. So, if you want to use binoculars for a wide range of uses (nature viewing, sports events, scenery, etc.), a lower magnification is fine. If you mainly want to use them for birdwatching, a higher magnification binocular will enable you to see more detail. Besides field of view, another tradeoff of using higher magnification binoculars is that the image will often shake a bit more, especially if you have unsteady hands.

Close Focus Distance – This is the shortest distance that a given binocular model can clearly focus on an object. In recent years, some optics companies like Eagle Optics have come out with some models with extremely short close focus distances – on the order of 5 feet! This can enable you to focus on close up wildlife like butterflies or amphibians for instance. If you want to do this with your binoculars, look for ones with a short close focus distance. Every binocular model is different, so you just need to try them out.

Eye Relief – If you wear glasses when you use binoculars, this number is important. If you don’t, it isn’t. Eye relief is the distance (in millimeters) behind the exit pupil lens (the one you look through) where you can still see the full field of view of the binoculars. Wearing glasses artificially increases the distance between this lens and the pupil of your eye to a point where it’s beyond the optimal distance the binocular was designed for. So, a eye relief is better – 12 millimeters or more. Every binocular is different, so ask for this number when looking at each model.

Optical Quality/Lens Coatings – The quality of the glass, construction, and lens coating system makes the biggest difference in the price of the binocular over any other factor(s). Better quality binoculars will present much sharper, brighter images to the viewer, which makes it much easier to identify whatever wildlife you’re looking at. You want binoculars with fully, multi-coated lenses and BaK-4 glass where possible. Some of the best features are ED (extra low dispersion) and HD (high density) glass. Basically, you should buy the best binoculars your budget can afford. In the long run, you will be far happier with your decision.

Other Features – Finally, binoculars come in either the Roof Prism or Porro Prism design. Generally, the Roof prism is more desirable, but can be more expensive for the same quality glass and optics compared to a Porro Prism. But, the more streamlined design and more rugged hinge design makes it worth it in most cases. Water Proof and Fog Proof are also desirable features if you’re going to possibly be using the binoculars in areas where you get a lot of moisture (like a damp forest) or where you may accidently drop them in the water (like canoeing). These can add to the cost, but may be a very good investment.

So, the key is to try a lot of different models to find the binocular that feels right in your hands and is easy to look through for your specific vision. This way, you can find a great pair that you will be very happy with for years.

About The Author

Kurt Hagemeister is a birdwatcher and nature lover of over 25 years. He is owner of a birdfeeding specialty store in Ann Arbor, Michigan, and has sold optics to customers for 15 years. In addition he is the owner of the website www.binocularexpert.com.