Binocular mount
Binocular astronomy
When I first started in astronomy I used 8x40 binoculars. I still use them regularly. Not only are they great for the night sky, but they also come in useful for lots of daytime activities. They're a great way to start exploring the night sky, and if you decide astronomy isn't for you, you'll likely still find a use for them. I was given my binoculars by an uncle who used them for watching horse racing.
Not long after starting using binoculars, I found the view was much better if I braced them against a wall or on a fence. I knocked together a simple wooden mount for them and put this on my dad's surveyors' tripod. The other big advantage of mounting binoculars is that you can point them at an object and then let other people have a look. I used my makeshift tripod at lots of local star parties and this setup proved very popular. People seem to find it easier to use binoculars (which they're probably more familiar with) than telescopes, and they're impressed to see that there's quite a lot of cool stuff to see with just simple binoculars.
There are many really neat things which just look much better in binoculars than even a wide-field telescope. One good example is the Coathanger (or Collinder 399). This is one of my all time favourite objects, and in fact I built my binocular mount just for looking at this object!
There are a couple of drawbacks with using a regular tripod to mount binoculars for stargazing. One is that it's very difficult to look at objects overhead, or nearly overhead. Another is that it's difficult for people of different heights to reach the eyepieces. This is particularly a problem if you have kids and adults together at a star party. A neat solution is the parallelogram binocular mount.
The parallelogram mount
The parallelogram means that the binoculars can be moved up or down
(i.e. adjusted to the height of each person), but they remain pointing
at the same place on the sky [see animation]. My parallelogram is built following the
dimensions given on Jan
van Gastel's page. The main difference is I used aluminium
C-channel instead of square tubes. This is 3/4 of the weight, and
easier to place the bolts into (I used 8-32 bolts and locknuts everywhere).
Jan suggests using a drill press to ensure the holes are in the correct
place for the parallelogram. I only have a hand drill, but I found
that by taping pairs of tubes together with masking tape when drilling
the holes, I could acheive the accuracy required. I did this for all
the holes: placing pairs of struts together, using them as jigs and swapping them round to
ensure all the holes where in the same places.
For mounting the binoculars, most of the sites I looked at suggested
using a ball-and-socket joint. I didn't have a ball-and-socket joint,
so I made something out of wood which resembled the platform I made
many years ago to go on my dad's surveyors' tripod. It's a simple L-shaped bracket with bolts and teflon pads forming the
bearings (much like a Dobsonian). The binoculars sit on an aluminium
arm (see photo to right) and are secured by wrapping an elastic cord
over the top of them and fastening this to the bolt (visible at the
bottom of the arm). This makes it very quick to install the
binoculars, and requires no tools. This animation should make it
clear.
The parallelogram mounts to the tripod and pivots in azimuth with a similar Dobsonian style bearing.
The counterweight comprises a pair of cheap 2.5lb lead barbell weights placed onto a 3/8" threaded rod. The only problem is that the hole through the centre of the weights is too large to allow the rod to bolt around the weight, so I used a plywood disc above and below the weights and tightened the nuts against these. I might eventually replace the weights with a 12V battery, so that the weight is not useless, and use this to run dew heaters. Attaching the counterweight rod to the parallelogram took a bit more thought. I eventually decided to use two short lengths of C-channel, drilled holes through these for the rod, and bolted the short tubes to the longer tubes of the parallelogram.