Before I go into the review, I would like to compliment Armasight for replacing a small part on my Spark Core night vision monocular that I reviewed recently. I have been complaining about how I had been unable to get a response from either their information email address or their relations person, but when I needed a small part their service department replied promptly and sent me the part within a week of my request. I found that impressive. Since the service people are efficient, that takes away much of my reluctance to recommend their products.
Getting back to the subject, binoculars are highly useful as well as fun. Being able to see things better is always entertaining, but besides that, it can help you locate game while hunting or uncover lurking threats before they can cause you harm. The problem with binoculars is that there are so many types and brands and the costs range from trivial to astronomical. What to choose? Your needs, budget, and expected uses play a role, of course, but it is still difficult to decide what to buy.
SurvivalBlog founder J. W. Rawles offered some advice to a reader that is worth recapping. He basically divided the needs for a prepper into two categories– fixed base security and patrol. He likes 7x50mm binoculars for base use and lighter, handier binoculars with smaller objectives like 7x35mm ones for patrol, though he did note the usefulness of having more power for those in a plains area with long sight lines. I think this is excellent advice and not just because JWR is the boss. I might, however, also consider a spotting scope for distance work over higher power binoculars.
We should probably go over a few things about binoculars before we go much further, though. The first number in the 7×50 refers to the magnification. The more magnification, the further you can see, with some caveats, like whether the air is clear, how much light there is, and the quality of the lenses. More magnification, however, means the binoculars get bigger and heavier, which makes them harder to carry and tougher to hold steady.
The second number refers to the objective size in millimeters. The larger the objective, the more light the binoculars transmit to the eyes, but again, the bigger and heavier they get. The objective is the end away from your eyes, by the way.
Light transmission is pretty critical and sometimes overlooked in choosing binoculars. One of the fun things to do with binoculars is to hand someone a pair of decent 7×50’s at night when their eyes have fully dark adapted. If they aren’t familiar with using binoculars at night, they will be in for a surprise and a treat. You can see things through the binoculars that simply aren’t visible to the naked eye. It is almost as if someone were magnifying the light. If my eyes are well adapted to the dark and there is good moonlight, I think I can do as well with the right binoculars as I can with most night vision gear that uses light intensification methods. Thermal is a different matter, of course. The point on which I have concern is in the shadows. Sometimes looking into shadows after watching the bright areas is difficult. Night vision, particularly when aided with infrared illumination, can see into shadows. Smart threats will use the shadows as will many animals, so it is important to see what is in them.
While there are many factors in binocular performance, there are two key ones that affect how well they work at night. The first can be computed by the purchaser, and that is how much light can potentially make it through the binoculars to the eyes, assuming all else is good. There are two methods of determining this, the first of which is the twilight factor. This involves square roots, which is something I have tried to avoid since high school math, but here it is. You multiply the objective size in millimeters by the magnification of the binoculars and then divine the square root of the product. Thanks to the calculators that come on computers these days, this is easier than it was in high school during my distant youth. In other words, if you have 7x50mm binoculars, you multiply 50×7 and get 350, and then you compute the square root which is 18.7. Binoculars with a twilight factor greater than 17 are usually considered good to go for night time use.
A second method, and the one I prefer since it avoids the dreaded square root, is to compute the exit pupil, which is done by dividing the objective diameter by the magnification. For example, when you divide 50 by 7 you get slightly more than 7. That number turns out to match the average pupil diameter in millimeters of a human whose eye is dilated for low light. The concept of how this works seems to me to be something like the idea of matching two holes up. If one is smaller than the other, the flow of light would be restricted by the smaller one. Since the maximum size of the hole in the eye that lets light through is seven for most people, if the hole in the binoculars– the exit pupil– is seven or larger, you will see as much as you can see, assuming you are young. Unfortunately, as we age, the pupil can dilate less, and by the time we are in our 60’s, we might be doing well to take full advantage of an exit pupil of 5. During the day, since the pupil is smaller, we don’t need as much light to pass through the binoculars, so smaller objectives will give you all you can use, hence there is no need for the big objectives during the day.
The second big factor in low light performance is how well the lenses and the anti-reflection coatings allow light to pass through. This is often expressed in a percentage. The higher the quality of the glass and how well the lenses are ground make a big difference, and the increasingly effective coatings developed by the optical industry are critical. Reflections on the lenses play hob with how well you can see through binoculars, and poor coatings cut down on how much light gets through. Unfortunately, the only way to know about these points for sure is to look through binoculars. Some makers do give figures on light transmission, which is helpful, and of course some companies have reputations for quality that you can rely on. Other brands may be a cipher, unless you can actually try them.
All this works for rifle and spotting scopes too.
Incidentally, you sometimes see the term “night glasses” applied to binoculars with a high twilight factor or large exit pupil. As well as 7×50’s, these include 8×56, 9×63, or 10×70 binoculars. The 7×50’s are often encountered in marine use as avoiding things in the dark is beneficial while afloat. Anything more powerful than 7×50’s are usually not used on boats, as they begin getting too heavy to hold steady and have limited fields of view, both of which make them hard to use aboard a boat, which is probably moving in multiple directions at once. Hunters in low light, however, often like more power and are willing to deal with the weight to see a bit further, so they often use 8×56 or more powerful binoculars. They are also generally on solid ground.
This brings up another number that is nice to consider, field of view. The more area you can see, the better off you are. If your view through the binoculars is too tight, it will be hard to obtain and maintain situational awareness and to quickly locate a subject. You often only get a fleeting moment to locate game, for example, and if your binoculars have a limited field of view, you may not have enough time. Field of view varies from binocular to binocular and is affected by many factors, but if all else is the same, more is better.
Besides the thoughts on magnification and objective size, JWR discussed the idea of how to spend our money. He felt it is better to have several pairs of decent binoculars than one pair of great ones. This also makes good sense. I subscribe to the one is none and two is one strategy for a number of reasons. First, I might smash a pair by accident. Second, there are three members of my immediate family and a few more in the next circle out. Being able to put more eyes on the problem is a good idea, which means needing more binoculars. Finally, it allows me to have an assortment of types of binoculars to cover different needs.
Alas, I also subscribe to a contradictory strategy– buy once, cry once. That means get the best and be done with it. The problem with this strategy, however, is that you may wind up with nothing at crunch time having waited until you could afford the best. There is also the question of needing more than one of something. Perhaps in that case, you buy something decent now and upgrade later with the earlier purchase then serving the second tier needs. This is often my strategy these days, as I worry that the pursuit of perfection is the enemy of the attainment of the good.
With all that overthinking in place, I hit a point where I had three decent pairs of binoculars on hand but no 7×50 night glasses when I spotted the $250 Steiner 7x50mm Marine models and decided it was time to push the budget and buy the German-made binoculars I have always wanted. I actually caught them on sale for a bit less than the current price, and if you shop, you might be able to as well.
The 7x50mm Marines are the entry level Steiner 7×50’s. They sell several more expensive models– the Police, the Navigator, the Military, and the Commander– ranging all the way up to $1050. They all have very similar form factors and are hard to tell apart without a close look. The difference between the Police and Marine models is apparently the color of the rubberized coating. The Police model is grey, and the Marine is black. While the Marine and Police are called waterproof, the Navigator and Military can survive 16 feet of submersion and the Commander 33 feet. The more expensive models also offer better optical quality. The Commander and Military provide a wider field of view with the Commander being even better than the Military. The Commander is the most costly and is two ounces heavier than its siblings and slightly larger due to the more ergonomic eyecups. The Military model has a range finding reticle.
While I, of course, wanted one of the top of the line pairs, reality settled in firmly, and I got the Marines. I have been very happy with them. They are heavy and bulky at 36.3 ounces and 8.1×5.5×3.0 inches. They aren’t, however, something you will want to carry all day on a hunt unless you expect to need low light capability.
Optically, they offer a sharp and clear view with good color rendition and great contrast. I have, alas, been spoiled by better binoculars in my life, but those cost far, far more. I still think back to a pair of NATO issue Zeiss glasses I got to spend a day with along with some Bosch & Lomb U.S. Navy-issue binoculars I used during a 5-day visit to a carrier. The B&L’s were pretty old, but the Navy has shops that kept them in excellent condition, and they were wonderful. They were also amazingly big and heavy. I will also note that the performance difference between my Steiners and those binoculars was very slight in comparison to the price differences.
One issue that the Steiners have no problem with is collimation– the alignment of the pair of lenses you look through. If they aren’t pointed the same, you will get a bad image and eye strain at best. At worst, the binoculars aren’t usable. One of the advantages of buying a name brand is that they will go through rigorous quality control, which largely includes accurate collimation.
They are made of a strong polycarbonate material and covered with a layer of rubber for protection. The optics are mounted to withstand 11 G’s. The waterproofing on the Marine and Police models “will resist rain, ocean spray, and potentially brief, shallow submersions.” The Steiner website advises, “If submersion is a serious concern, I would highly recommend the Navigator’s.”
The ergonomics are quite good, as they fit my hands well. I do miss center focusing, however. Steiner has what they call “Sports-Auto-Focus” that they claim gives you a good image from 20 yards to infinity. You get it by focusing each eyepiece to your own eyesight and then leaving them alone once you get it set to your tastes. My problem is that I wear glasses and sometimes like to use the binoculars with them on and sometimes with them off. That means two focus setting that can be easily accomplished with center focus, which adjusts both sides at the same time without having to adjust each eyepiece separately. There are also times you might want to focus on something closer than 20 yards, such as a bird or butterfly, which once again means twisting both eyepieces. The lack of center focus is pretty common with 7×50’s though. The 20 yards to infinity usually works quite well at sea, which is one of the primary locations for use of these binoculars. Truthfully, it works well on land too unless you need to look at something up close.
You get a neck strap and padded case. I found the strap a bit narrow for comfort and somewhat slippery for over the shoulder use, so I wound up replacing it with an OP/TECH one made of a stretchy wetsuit-like material. It will stick better to clothing and is wider to spread out the weight. The case isn’t to my liking either. You have to unzip it all the way around to get the binoculars out. I have other binocular cases that close from the top and are held shut with magnets or Velcro, which make it faster and easier to get the binoculars out.
I have really enjoyed these binoculars, particularly in the dark. It is amazing what you can see through them that you can’t see unaided. I have been curious, however, if I really am seeing more with them than I might with a pair of equal quality 8×42 binoculars. The 8×42’s have an exit pupil slightly greater than 5, so they pass less light, but I’m at the stage of life where my eyes just don’t work as well at night. I recently had a chance to use a pair of very nice Nikon Monarch 7 8×42’s, which are very well rated in the bird watching community. I was surprised to discover they came from China, but it did give me a chance to compare night vision with the two roughly comparable quality binoculars. I was sad to discover that the extra light gathering ability of the 7×50’s might be wasted on me. I think I see very slightly better with them, but I’m not sure. The Nikons cost almost twice what the Steiners do, and that might be a factor. I am sure, however, that my son will be able to see more using the 7×50’s with his much younger eyes, but for me the lighter 8×42’s might be all I can take advantage of.
– SurvivalBlog Field Gear Editor, Scot Frank Eire
