P3D military stereo binoculars

[Peter Abrahams <telscope@xxxxxxxxxx>]

Last week, someone mentioned that while at a camera show, they saw
something like a military binocular with lenses spaced a foot or two apart.
 I couldn't answer at that time, and can't find the post, so I'm going from
memory.  
There is a type of binocular called a 'battery commander's rangefinder'
that was extensively used in WWI & WWII.  A normal rangefinder takes a
certain time to acquire the target and find the range (by superimposing two
images or other means.)  Not only is this process very hazardous while
under fire, but many targets are too ephemeral to locate & range in this
manner.  A battery commander's rangefinder is a binocular with objectives
spaced 18 to 28 inches apart, and this increased distance gives a greatly
accentuated sense of depth.  They were primarily used to range shell
bursts, and effectively give a rough sense of distance.  Like all military
equipment, they are rather bulky, and the larger units were used on tripods
with geared heads for altitude & azimuth.   Used in peacetime, the views
are really beautiful.  These are sometimes found at military collector's
shows, but condition is usually not good.  Alignment of the two images is
more difficult than with a standard binocular.
I wrote an essay on stereo binoculars & rangefinders, which I could e-mail
as a word doc attachment to anyone interested.
I also have a few of these that are taking up too much room & could be
surplused.
_______________________________________
Peter Abrahams   telscope@xxxxxxxxxx