Christmas came early last week when I received a new pair of binoculars! Swarovski introduced two new models last year: a 10x52 and a 14x52. The first number, 10 and 14 in this example, is the magnification. The second number, 52 in this example, is a measurement of the objective lens in millimeters from edge to edge.

For many years, I’ve used a pair of Swarovski 12x42 NL Pure’s. Twelve power is a lot of magnification to hold steady, but I enjoyed the additional magnification. Having a 42-millimeter objective lens made the binoculars fairly compact and ergonomically comfortable in the hand.

However, when the new 52’s came out, I knew it was time to upgrade. The challenge was deciding which pair I should get, the 10’s or the 14’s? It wasn’t until I was over at the Verde Valley Birding Festival in April that I got serious about trying out the two models.

Usually, when I have the option of more magnification, that is the option I choose. A ten-power binocular has twenty-five percent more magnification than an eight-power, and a twelve-power has fifty percent more magnification than an eight-power.

However, higher magnification has its downsides – a narrower field of view, less light gathering, and it’s harder to hold steady. I’ve always felt that more magnification trumped the downsides. After all, what is the whole point of binoculars, if it isn’t to magnify the object you are looking at?

Surprisingly, I liked the ten-power over the fourteens. You might ask, why? Sometimes it is hard to verbalize the subjective nature of why one pair of binoculars is “better” than another.

I mentioned light-gathering earlier. When light enters the objective lens, travels through the binocular and exits the ocular lens (the lens you look into), the amount of light exiting the ocular lens is referred to as the exit pupil. The size of the exit pupil can be calculated by simply dividing the magnification into the size of the objective lens.

Why is gathering more light “better”? Light illuminates. Light clarifies. Light improves the overall optical image sharpness and resolution. Interestingly, the world of optics is a world of trade-offs. By going from a 12-power to a ten-power, I “lost” magnification, but I gained light.

For example, my old pair of 12x42’s had an exit pupil of 3.5 millimeters. This is the diameter of the ray of light exiting the ocular lens and hitting my pupil. With my new 10x52’s I now have 5.2 millimeters of light hitting my pupil.

Am I boring you yet?

I actually love selling binoculars, as I feel every time I get someone into a new pair of binoculars I am doing them a service. Chances are, their new binoculars will be vastly better than their old pair, and the new pair is going to greatly improve their bird watching/nature observation experience.

No one pair of binoculars is right for everyone. It has to be the right size and weight, and feel ergonomically comfortable in the hand. As mentioned earlier, when you increase magnification, you diminish light gathering, narrow the field of view, and you increase the jiggle-factor. The positive is more magnification.

In the end, you have to decide, what is of most importance to you. Is it size? Is it weight? Is it magnification? Is it light gathering? Is it field of view? Is it steadiness?

The day I received my new pair of Swarovski 10x52 NL Pures, I took them out for their maiden field test. Where did I go? Willow Lake. Next week I’ll tell you about an amazing find at Willow.

Until next week, Happy Birding!

Eric Moore is the owner of The Lookout, in Prescott, where you will find a Hallmark Gold Crown Store, wild bird products, and Swarovski and Vortex optics. Eric has been an avid birder for over 55 years. Eric can be contacted at eric@thelookoutaz.com.