Mounting Binoculars for Astronomy

Mounting Small Binoculars

Most people start out with binoculars similar in size to a 10x50 and consider ways of mounting these on a photo tripod, usually by some sort of L-bracket, unless the binocular has a built-in mounting bush:

Central Image
Top Row, L to R: Hinge clamp, Standard L-bracket, Roof-prism L-bracket, Universal Astronomics custom L-bracket
Bottom: ¼" mounting bush on prism housing

Hinge clamp: As the name suggests, it clamps onto the central hinge of porro-prism binoculars. May be unsuitable if the binocular has a wide focusing "band" as opposed to a narrow focusing wheel.

Standard L-bracket: Screws into the ¼" mounting bush at the distal end of the central hinge, if the binocular is equipped with one.

Roof-prism L-bracket: Similar to above, but with recesses for the objective tubes of roof-prism binocualrs (which are closer together than in porro-prism binocs).

Universal Astronomics custom L-bracket: Similar to above, but is a proprietary bracket that fits the Universal Astronomics mounts.

¼"mounting bush on prism housing: Rarely seen nowadays. Care needs to be taken that the tripod head allows the binocular to be mounted in such a manner that the observer's nose does not foul the tripod head! Offers no facility for tilting the binocular side-to side.

Tripods and Heads

The tripod and head should be chosen with care. As the binocular is pointed at higher altitudes, the height of the eyepieces decreases. Simultaneously, the height of your eyes increases as your head is tilted back. Some form of height adjustment is therefore necessary. This usually takes the form of a raisable centre-post on the tripod.

The tripod must be sturdy enough so as not to permit excessive vibration, and high enough to enable the observation of high-altitude objects from a standing position (photo tripods and heads vary from infuriating to impossible to use from a seated position for high altitude targets).

Heads for photographic tripods often do not, when used as intended, permit altitudes in excess of about 60°:



Whilst this may be as high as you can comfortably observe with "straight through" binoculars, those with 45° eyepieces can comfortably observe to the zenith. Photo- and video- heads are usually designed to permit the camera to point straight down, so the trick is to reverse the head and put the binoculars on the "wrong" way:



Any handle on the head will probably need to be reversed, and may therefore get in the way of tension controls, clamp levers, etc.

A consideration with large, heavy binoculars is that the centre of mass of the binoculars is some distance from the altitude fulcrum of the head so, at altitude, there is a considerable turning moment on the head. Any altitude tension control may need to be set at or near maximum. This, combined with the cantilevered weight of the binocular, can make the the set-up awkward to use.

Parallelogram Mounts

Parallelogram mounts (P-mounts) offer a great deal of versatility. They are often cited as advantageous for star-parties or other group observations, because they permit the height of the eyepieces to be changed without changing the target object, but the same is true (albeit to a lesser extent) of centre-post tripods. Basic incarnations of P-mounts may require that the binocular is pointed back over the tripod, but there are sophisticated designs that are much more flexible; the epitome of these is the Universal Astronomics deluxe mounting head:



This permits the binocular to be adjusted so that its centre of mass is exactly aligned with the altitude fulcrum, so that the binocular does not exert a turning moment on the fulcrum. The consequence of this, together with the counterweighting, is that the the binocular feels almost as though it is floating in the air. Additionally, the additional azimuth fulcrum permits the binocular to be pointed at a very large proportion of the sky (about a third of it) without any significant change of observing position. This is obviously a consideration if you prefer to observe sitting down:

The mount shown above is the Universal Astronomics T-mount, a short parallelogram. Longer parallelograms can permit reclining, seated, and standing observation from the same tripod height. The consequence is a much longer turning moment on the tripod and support, resulting in vibrations taking longer to damp.

P-mounts are amenable to home-construction if you have woodworking skills. See links below.

Other Mounting Options

CloudyNights Reviews of Binocular Mounts
Comet Couch
Florian's Binocular Viewing Accessories (includes a home-made mirror mount)
Craig Simmons' Binocular Chair
Parallelogram Binocular Mount (good, simple P-mount with full construction plans)
Scott's Binocular Mount Page (excellent, versatile home-made P-mount)
Sky Window (commercially made mirror mount)
Star Chair (the ultimate observing chair)

© 2004