Monday, December 11, 2006

A closer look at Binoculars – advice from a birder.



I don't think Consumer Reports could have been more out of optical alignment when it comes to recommending binoculars for birdwatching. Whether you're a birder, hunter, or general nature enthusiast looking for a pair of binoculars, here is where I think Consumer Reports' "A Close Look at Binoculars" (Jan 2007) ought to be filed:



While they're entitled to their opinion, those of us who are intimately familiar with binoculars and use them for birding were quite bewildered by their top picks. I've used most of the binoculars on their list and some of them are fine compact binoculars – but that's precisely the problem. When birding is the pursuit, I generally expect to see a lineup of 8x42 bins topping the list and perhaps a few 10x42 bins for those specialized birder needs; hawk watching and shorebirds. Naturally, there will be exceptions. A person I regularly bird with swears by her 10x42 for warbler watching.

The reason most birders go with an 8x42 is because they represent the best combination of magnification, aperture and physical size to deliver a bright image at a moderate power with a decent field of view that can be held steady. It's that simple! Oddly enough, there wasn't a single 8x42 out of 16 binoculars from a total of 36 they looked at. To illustrate the trouble with compact binoculars, take a look at the following Exit Pupil diagrams (exit pupil is the diameter of the shaft of light exiting the eyepiece of a binocular):



Exit Pupil is calculated from aperture divided by magnification (42 / 8) = 5.25mm. In bright light your pupil may narrow down to 2mm and some of the 5.25mm shaft of light will hit your iris (above left). But at dawn or dusk when your pupil is dilated to 5mm or more, an 8x42 will deliver about as much light as your pupil will take (above right).



Consider that Consumer Reports recommend a 10x21 with an exit pupil slightly over 2mm – such a binocular is worthless in early morning under a wooded canopy. You'll hate it!

Consumer Reports graded the binoculars on best sharpness, brightness, focus, grip and durability. They subjected them to temperature extremes over several hours and even "swung them against a hard surface." Perhaps that explains why so few full-size binoculars made their list – the bigger they are, the harder they fall. I wonder if they saved that particular test for last?

Addendum:

Here are my personal favorite binoculars across various price ranges. These are the same ones I would recommend to birders over the phone.

Under $100

1. Bushnell Natureview 8x42 Porro
2. Leupold Yosemite 6x30

Quick points: Both binoculars offer excellent optical quality for the price. The Yosemite is a great choice for young birders. While the Natureview isn't waterproof, the Yosemite is. Neither binocular is fog proof, though.

Under $200

1. Vortex Sidewinder 8x42
2. Bushnell Excursion 8x42

Quick points: Both have a super wide field of view. Great close-focus on the Sidewinder.

Under $300

1. Eagle Optics Ranger SRT 8x42
2. Nikon Monarch ATB 8x42
3. Audubon Equinox HP 8x42

Quick points: The Ranger and Monarch are the lightest weight full-size roof prism binoculars around. Both binoculars have received glowing reviews over the years. The Audubon HP is a terrific runner-up (I own a set).

Under $500

1. Vortex Viper 8x42
2. Celestron Regal LX 8x42

Quick points: The Viper is super bright in low-light...I would like one!

Under $800

1. Vortex Razor 8x42
2. Minox HG 8.5x43
3. Nikon Premier SE 8x32

Quick points: The Razor has excellent resolution at distance. The Nikon SE is simply one of the all-time best views through a binocular you'll get (I own one).

Under $1000

1. Zeiss Conquest 8x40
2. Vortex Stokes DLS 8x42

Quick points: The Conquest has good sharpness, but color fringes quite a bit. The DLS is very bright and extremely durable. My DLS is two years old, has held true alignment even after being dropped and has been rained on many times without a problem.

Under $1500

1. Leica Trinovid 8x42
2. Nikon Premier LXL 8x42

Quick points: Super-premium optical quality for those unwilling to spend at the next level.

Under $2000

1. Swarovski EL 8.5x42
2. Swarovski EL 8x32
3. Zeiss FL 8x42

Quick points: Naturally, the 8.5 for best low-light performance, but have you ever looked through the EL 8x32? Phenomenal binocular. The Zeiss FL has the best color correction I've seen, but it's a little soft on the edge.