Image-Stabilize Your Binoculars!
You can pay close to $1,000 or you can beat the binocular jiggles with scrap wood and an evening's work.
But hand-held binoculars have one huge problem. They jiggle. You can’t see nearly as much in a jiggling view as in a still one.
Putting the binoculars on a tripod doesn’t work if you want to look much above horizontal. Special parallelogram-type binocular mounts let you aim all over the sky, but their bulk (and occasionally poor design) work against binocular observing’s handy, quick-look appeal. The modern breakthrough solution is the image-stabilized binocular, which uses electromechanical magic to calm the jittering with the push of a button. But it doesn’t come cheap. The runaway market leaders are the Canon IS series of imaged-stabilized binos, but the 15x50s that I lust for approach $1,000. Ouch!
However, I’ve discovered that you can add image stabilization to ordinary binoculars for practically nothing, with scrap wood and less than an evening’s work.
Beating the Binocular Jitters
Let’s consider the problem. Hand-held binoculars can move in six degrees of freedom (motion in all three dimensions, and rotation in all three dimensions). But only two of the six actually cause the image to move in your view: rotation of the binoculars around the two axes oriented left-right and up-down. A sailor or an airplane pilot would call these motions "pitch" and "yaw." Stabilizing the view means increasing the binoculars’ moment of inertia resistance to rotation around these two axes.
To achieve this, I first tried attaching my binoculars to a big, vertical plus-sign made of wood with weights on the four ends. This certainly helped, but it was awkward. I next tried a big wooden T, which had better balance but didn’t steady the view as much as I hoped. The most efficient design, I realized, would be a single rigid stalk extending straight in front of or behind the binoculars with a weight on the far end. But if it was in front, the balance would be awful, and if it was behind, my head would be in the way.
At this point my friend Eric Johansson of the Amateur Telescope Makers of Boston had a brainstorm: make a long, rectangular frame extending front and back with your head between the sides of the frame. Pictured above is my result: a frame 5 feet long, with a heavier piece of wood in back to increase the moment of inertia. The binoculars ride on a tiltable cross-piece positioned so that the frame balances on the shoulders with the binoculars at comfortable eye height. I call it my Image-Stabilizing Binocular Frame.
It works! When my 10x50s are attached to it (either with a bungee cord as shown below, or better, with a ¼-20 bolt into the binoculars’ tripod socket between the barrels), the jiggles are greatly reduced. I can see much more, yet still have total, hand-held freedom of movement to aim anywhere high or low.
My frame is made with two 5-foot lengths of 1-by-2 pine with cross members at the ends. How long should yours be? A short frame is less awkward to transport, but the longer it is, the steadier the views. Five feet was my tradeoff between convenience (to fit in my small car) and good stabilization. The two long sides of the frame are held apart by an 8-inch-long piece of 1-by-2 in the front and 2-by-6 in the back. (Eight inches is about right for my shoulders while allowing a winter parka hood inside.) The rear piece also functions as a counterweight.
The binoculars sit on a pivoting crosspiece consisting of another piece of 2-by-6 with a vertical slat screwed to its front, as shown. But it might have been better to use a 2-by-8 instead; after the photos here were taken, I glued a piece of 2-by-3 on top of the 2-by-6 to add height so I wouldn' t have to hunch to look if the binoculars are held to the top by a bungee cord as shown. Better would be to attach the binoculars to the vertical slat at whatever is the ideal height for you, by using a ¼-20 bolt through the vertical slat and into the binoculars' tripod-mounting socket.
Make the crosspiece assembly, attach your binoculars to it, then slide the assembly up and down in the frame to find where the frame balances on your shoulders with the eyepieces comfortably at your eyes. You can hold the crosspiece to the frame temporarily with string or rubber bands while you make this balancing adjustment. I found that the frame handles best if it’s balanced to be just a little back-heavy.
Attach the crosspiece to the frame with a single screw on each side. The screw should go into the 2-by-6 close to its bottom, as shown. The vertical slat now serves as a handle to let you pivot the binoculars up and down a bit to position the eyepieces most comfortably to your eyes for any viewing angle.
For proper pivoting, drill holes through the sides of the frame big enough for the screws to slide through freely; the screws should bite into the crosspiece only. I put a split-ring spring washer under the screw head on each side to make it easy to adjust the pivoting friction by tightening or loosening the screws.
Brave New Views
With my 10x50s mounted to the Image-Stabilizing Frame, I can see the galaxies M81 and M82 in Ursa Major for the first time through my suburban sky. All four of Jupiter’s moons are much easier to see and hold, and I even glimpsed Saturn’s moon Titan (with difficulty) for the first time in binoculars. I can easily split once-frustrating double stars, such as the little 8th-magnitude pair Burnham 536 centered in the Pleiades, and resolve vague open clusters into swarms of points. Hundreds of formerly “telescopic” features hold steady on the Moon.
Testing showed that with the frame, I can see objects 0.5 magnitude fainter than with the same binoculars hand-held. This means that on average, you can successfully hunt down twice as many astronomical objects of any given type. (If you do the math, it turns out that seeing 0.5 magnitude deeper just about doubles the volume of space that you can examine for objects of a given luminosity.)
Nevertheless, some wavering of the image remained and I wanted to get rid of it totally. Experiments revealed a law of diminishing returns: even a big, awkward frame nearly 8 feet long with barbell weights on the ends left some residual wavering.
The simple solution, I found, is to have something behind you, such as a wall, post, or car, that you can touch the back of the frame against once you've located your target. For this purpose, I stuck a pipe meant to support a bird feeder into the middle of my lawn. Merely backing up slightly and pressing the rear of the frame to the pipe makes the stars hold still! Using the Image-Stabilizing Frame this way increases the reach of my binoculars by about another 0.3 magnitude (increasing the number of observable objects by another 50%), makes Titan plain as day, and even begins to resolve the Trapezium multiple star in the Orion Nebula!
Nowadays I leave my 10x50s on the frame all the time. It stands by the door ready for a moment’s use. Okay, it won’t fit in a backpack. But it didn’t cost $1,000, and it doesn’t eat batteries.
Try making one for yourself, and see how much better a stabilized view really is.
Update: Here are some other people's versions.
Alan MacRobert, a Sky & Telescope senior editor, is proud of his geekitude and thinks do-it-yourselfing builds character.