(For the travel-friendly Bino Body Mount see: Bino Body Mount - build a travel mount for binocular astronomy)
Binocular observing is very relaxing, or should be, and really lets you connect with the sky and the night world around you. In general, I recommend 10x50 binoculars for astronomy. In binoculars, the first number, 10, is the power of magnification and the second number, 50, is the diameter of the objective lenses in millimeters, the big ones that point toward what you are viewing. 10x50s are high enough powered to view some individual star clusters and some nebulae and galaxies. Most people can hold them by hand without too much shake or fatigue. Larger binoculars will require some sort of stabilization.
Even low power binoculars- 7x35 or 8x42, for example- can benefit from stabilization of some sort. Few people, if any, can hold binoculars without any shake, and if you’ve ever viewed through binoculars on a tripod, parallelogram mount, or even a monopod, you surely noticed how much better you can resolve individual stars and details. A mount that actually holds the binoculars for you also frees up your hands to use a phone app, make adjustments, etc.
I built a tripod and parallelogram mount many years ago from plans in Astronomy Magazine. This setup worked well for holding my 10x50 binoculars steady, but it was heavy, bulky, and cumbersome to move around. I don’t have a picture of it, but the drawing below gives you an idea of the heft of this behemoth, which was mostly made of oak.
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| The tripod and mount from Astronomy magazine, Aug. 1995 |
Recently I bought used Garrett Optical Signature 15x70 binoculars (same as Oberwerk Ultra or Orion Resolux) and I clearly needed something to mount them on. These weigh 5.5 lbs! I don’t like the idea of a monopod because it ties up my hands and I wanted to be able to look at my charting program, Sky Safari Pro 6, on my phone to identify objects and generally to be able to relax my arms, as well as pull out my handwarmer, adjust my hat or gloves, etc. So I designed a simple mount that sits on my reclining chair and holds the binoculars for me.
If you are interested in building one, it’s easy and inexpensive. Here’s how.
First, you need a reclining chair. I recommend a “zero gravity chair.” Unlike the old style where you have to lift up both armrests to move the chairback forward or backward, the zero gravity chair pivots by putting pressure with your feet on the footrest or your back on the backrest. If you will be traveling to your observing site, pick one that is not too big to fit in your car easily. Mine is narrower and fits standing up behind the front seat. Most, if not all of them, have some kind of lever or knob on each arm to lock the chair in any reclining position, which is very useful when you are observing a particular area or object for a while.
Then pick up the listed materials at a home improvement store or online. A parts list is included at the end of this article with some links. Adjust the measurements below for your specific situation: the dimensions of your chair, the distance from the binocular eyepieces to your eyes when mounted on a tripod adapter, and your own body. You want the eyepieces to line up with your eyes exactly as you would hold the binoculars in your hands. The nice thing is the wood pieces are very cheap, so you can experiment, drill holes, and redo it if it doesn’t come out right.
The frame consists of six pieces of 1x2 furring strips. You can use better wood if cheap wood offends your sensibilities, but it’s not necessary. These include two longer legs (30”) that rest on the point where the chair back meets the seat (the pivot point for the chair), two shorter legs (18”) that rest on the frame of the chair back, one cross piece to hold the binoculars (18-3/4”), which I call the bino bar, and one cross piece for strength and rigidity (21”). The sides form triangles with the vertices pointing toward the sky.
The length of the two crosspieces will depend on the width of the chair frame, since you want them firmly sitting on the frame. Mine is 19” wide, which is narrow compared to some chairs, but I needed it to fit behind the front seat of my car. I added 2” feet to the long legs that rest in the pivot point and 3-1/4” feet to the short legs that rest on the chair back frame. These are also made from furring strips.
I added felt to the bottoms of the feet to protect the chair frame and potentially damp some of the vibrations. I also cut a couple of extra pieces for the short legs so I could adjust the distance for two different binoculars. The extra feet attach with velcro and I can store them velcroed to the frame when not in use. [8/28/24 update: I found the bare wood squeaks terribly on the metal chair frame, so I added adhesive craft felt to the points on the chair frame that contact the feet.]
(Above) Extra spacer velcroed to the feet that rest on the chair back frame, which allows for using a second binocular that has a different eye placement distance. When not in use, the feet are stored on the black velcro strip just above the permanent foot in the image.
Each pair of long/short legs is hinged with a 2” 1/4-20 carriage bolt. Drill a 1/4” hole 1-3/4” from the tops of the legs and hammer the bolts into the inside of the short legs, which go on the inside of the long legs, so the square part under the rounded bolt head will grab the wood. Use 1/4” fender washers on the outside between the knob and the long leg, and a 1/4” neoprene washer between the two legs so they are less likely to shift when tightened.
I originally used wing nuts on the ends of the carriage bolts, but found 2" 1/4-20 five star knobs are much more comfortable to use and worth the slight extra cost. The angle of adjustment of the legs depends on you and your chair.
(Above) Closeup of the main hinge, showing the placement of the carriage bolt, neoprene washer between the furring strips, and fender washer (not visible here) and star knob. The short legs go inside the long legs. Note the power bank velcroed to the bino bar below.
The bino bar is an 18-3/4” piece of furring strip, with the upper edge 6” from the tops of the short legs. The length of this piece will be dictated by your chair frame width. I screwed a 1/4-20 hanger bolt into each end and used the same 1/4” fender washers and five star knobs as I used for the hinges. The bino bar is drilled in the center with a 1/4” hole, and a 1/4-20 stud knob that I had laying around holds the tripod adapter.
Both the bino bar and tripod adapter can be slightly loosened to allow for aiming the binoculars up and down and side to side. I can cover a lot of sky this way without moving the chair.
(Above) The bino bar holds the binoculars. The tan colored knob holds the tripod adapter, which has a knob that screws into the binocular adapter threads. The lower set of knobs allows you to adjust the angle of the bino bar, and therefore the binos, to provide for comfortable eye placement. Note the orange bungee on the left side that makes sure the mount, which is just resting on the chair frame, doesn’t fall forward when the chair is upright for low altitude viewing. I have since added a screw-in hook to the left short leg to attach the bungee, since it tended to slip off the bino bar. [8/28/24 update: I also added a second bungee on the other side so the frame doesn't twist.]
(Above) The position for low altitude viewing. Because I have to tilt the mount off the chair, the bungee ensures it doesn’t fall all the way forward and off the chair. When not in use, it just clips to the chair laces.
(Above) How a tripod adapter fits on binoculars. Most binoculars should have a plastic cap that unscrews to reveal the female adapter threads. Some smaller or inexpensive binoculars may not have adapter threads. You’ll need to handhold those.
(Above) By keeping the knob that holds the tripod adapter to the bino bar very slightly loose, I can pivot the binoculars left or right to cover about 30 degrees of sky. Leave enough slack in the dew heater wires to allow for this movement (note wire on right). The bino bar can also be adjusted with the side knobs (lower set in image) to allow for comfortable eye placement. Tilt the bar up slightly when viewing at the zenith, since these chairs don’t recline completely to the horizontal. Always tighten up the knobs when you are moving the mount to get in and out of the chair. That will ensure the binoculars don't swing around by mistake. That glare shield around the binocular eyepieces is called a Bino Bandit. While pricey for a little piece of neoprene, it works well to shield your eyes from glare or even sky glow.
Screw the strengthening cross piece into the front of the long legs 10” from the top. This is the piece that will hold the optional dew heater controllers and powerbank.
For dew prevention on the objective lenses, the simplest and cheapest solution is to fabricate dew shields from 1/8" black craft foam, cut and rolled to fit tightly over the objective lenses and wrapped tightly with duct tape. Something like this example from the Cloudy Nights forum.
I use these SVBony dew heater strips, powered by an INIU 20,000 mAh powerbank with a piece of red taillight tape filtering the percent charge indicator on the powerbank. Most powerbanks have low current cutoff, as this one does, so I can’t run the heaters on low- they shut off after a few minutes. On medium I can get about four hours constant use, which is enough for my purposes. Anker makes some powerbanks that work with low current devices. These will be listed as capable of “trickle charging.” Regardless, you will need one with two USB ports. [8/28/24 update: If you have an Aldi store nearby, I found that their "Bauhn 20000 mAh Fast Charging Power Bank," which is an occasional (maybe one time) "Aldi Find," has this low current capability and has two USB ports. It was only $15 in my local Aldi. Keep an eye out in case they offer it again. I've also seen it resold on eBay.]
The heater strips on the SVBony have red indicator lights on the controllers, and you may want to put red tape over them to dim them down. They don’t bother me where I have them mounted, though. If the eyepieces fog up from my own breath or sweat, I use a tiny handheld pocket fan to clear them off quickly.
(Above) The dew heater strips are wrapped around the binocular objectives and the wires are routed to the controllers (on the left, above the left foot) and the powerbank (above the right foot). Everything is just velcroed to the mount cross piece and long legs.
(Above) When not in use, the dew heater strips are wrapped around the bino bar out of the way. This is how I store and transport the mount so I don’t have to do anything but attach the powerbank to its velcro strip and wrap the heater strips around the objectives. Note the extra feet velcroed to the short legs for storage when not using them.
The powerbank is mounted to the inside of the strengthening cross piece with adhesive-backed velcro, as are the dew heater controllers and connectors. When packed up, I leave them on the frame, wrapping the heater strips around the cross piece. I could loosen the hinge knobs and fold it as small as I can, but I usually just leave it set where I will use it and just set it on top of the other gear in my car. I suppose you could design a way to fold the frame completely flat, but it’s fine the way it is for me.
To use the mount, sit on the chair, attach the binoculars, set the long legs on the chair frame where the seat meets the back, which should require turning the mount a little sideways to fit the feet in, then lay back and set the short legs on the back frame of the chair. Adjust the angle with the top knobs until you have a comfortable viewing angle.
When not using the mount, I put the lens caps on the binoculars, unplug the dew heaters from the powerbank to save juice, and set the short legs on the chair sideways, over the arm of one side. I have the outside faces of the frame painted white for visibility, and the faces toward me painted black. I can throw a towel over the frame if I have glaring lights in the vicinity.
I added some 1” pipe foam insulation to the chair frame where the feet rest to help dampen vibrations and protect the chair finish. I also put one around the footrest to make it more comfortable.
(Above) Rather than place the whole mount with the binoculars on the ground when getting in and out of the chair or not using it, I just set it over one arm, with the short arms resting on the chair seat. This gives me room to get in and out without having to juggle the mount at the same time. I cover the objectives with lens caps and turn off the dew heaters when left in this position.
Parts list:
(2) 1x2” x 8’ furring strip for frame. Look for a nice straight piece with no twists or bends or splits. You can use a treated piece if you don’t want to paint it. Two pieces required if your chair is wider than mine. Get two anyway in case you mess something up.
Scrap wood or another 10 to 12” piece of furring strip for the feet
Stick-on craft felt and adhesive backed velcro strips for feet padding
(2) 1/4-20 2” carriage bolts for hinges
(2) 1/4-20 2” hanger bolts for bino cross piece
(2) 1/4” hole x 1-1/4” diameter neoprene washers
(6) 1/4” hole x 1-1/4” diameter fender washers
(4) 1/4-20 2” diameter threaded five star knobs (internal threads where the bolt can protrude through the center)
(1) 1/4-20 stud knob (make sure the threaded stud isn’t too long or you’ll need a spacer - something like this stud knob from Amazon with a 1” stud.)
(1) 1/4-20 tripod adapter (make sure it is thin enough to fit between the barrels of your binoculars). Something like this heavy duty adapter from Oberwerk or this adapter from Barska (which I think is the same but less expensive) for a typical porro prism binocular.
(4) 1-1/4” wood screws for attaching strengthening cross piece
Optional: dew heaters, powerbank or battery with two USB ports, and adhesive backed velcro strips if you need dew prevention; pipe insulation for comfort and vibration damping.
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