Inclement weather can cause a plethora of problems when it comes to the operation and care of hunting optics. And Tom Hogan, technical training coordinator for Swarovski, says that in the optics world you definitely get what you pay for. Not only do higher-quality optics stand a much better chance of operating under extreme conditions, you can simply see better with the good stuff. There’s no eye strain or headaches associated with topnotch optics, there are generally wider field-of-views, brighter images and better color transmission that will allow you to spot more game. Here’s how Tom weighs in on the attributes of great glass for foul weather use.
GK: Tom, obviously there’s a correlation between price and quality in sporting optics. How important is it to use high-quality optics when hunting under adverse weather conditions?
HOGAN: The benefits of high-quality glass often mean the difference between seeing and not seeing game. A very good friend of mine was using a moderately expensive set of binoculars on a Colorado elk hunt a couple of years ago. His guide, who happened to be using our 10X50mm SLCs, spotted a good bull just inside a tree line at 250 yards. My friend couldn’t pick the bull up in his binoculars. The guide let him use the 10X50mms and he found it immediately—he had seen the elk in his own binoculars but thought it was a boulder. He ended up shooting that bull. There’s a great deal of emphasis in high-quality glass to get the truest possible color to your eyes that contributes to better contrast. The higher-quality glass used to begin with contributes to better resolution or ability to see detail. The lesson here is that you might still miss picking up game with lower-quality optics even when you’re looking right at it. Good overall construction also means keeping nitrogen in and moisture out, and the strength to keep the binoculars in alignment with rough use or having a riflescope that will hold a zero. Generally speaking, there’s a greater chance an optical device can fail to perform (fogging up, reticles breaking, etc.) in adverse hunting conditions in the lower dollar ranges.
GK: What would be your optics recommendation for a hunter who’s going to hunt whitetails in Saskatchewan, where the temperatures are likely to dip well below zero and snow-covered brush could cause moisture problems?
HOGAN: Use scope covers in the field if you’re walking through snow-covered brush, especially on a riflescope—preferably flip-ups or something that can be removed relatively quickly. Ocular covers or rain guards are of great importance to keep water/snow off the eye lenses on binoculars. Water on the eye lenses hinders vision, not to mention the possibility of the water freezing as temperatures dip. Make sure your optics are waterproof for adverse conditions. Most manufacturers make waterproof optics now, but some are just a little more waterproof than others. Modern Swarovski riflescopes are waterproof even with the turret caps off. Try to test this during the preseason before you go on an expensive trophy hunt. Make sure power rings on scopes or focus wheels on binoculars turn easily enough in very cold temperatures. There are greases that are used on internal mechanical parts that need lubrication. Some greases can make the movement of these parts very sluggish. Swarovski’s functional temperatures are minus 4 degrees for spotting scopes and riflescopes and minus 13 degrees for binoculars. The optics will work at temperatures much below this, but these are the temperatures at which the grease will start to thicken up.
GK: What can hunters do to prevent their optics from fogging up?
HOGAN: Good-quality optics shouldn’t fog up internally (as long as the nitrogen remains inside). If you have internal fogging in an optical instrument it should go back to the manufacturer for repurging and possibly new seals. I run into more outside fogging issues, especially concerning ocular lenses on binoculars. If you take binoculars that have been sitting in the truck all night in cold weather and place them up to your 98.6-degree eyeballs the next morning, there’s a chance the eye lenses will fog up. Eye relief on binoculars usually ranges from about 12mm to 23mm (about 1/2-inch to an inch). Choose binoculars with a generous amount of eye relief—15mm or greater—that will keep them farther away from your eyes if you know you’re going to be hunting in extreme cold.