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Geoffrey Kolbe wrote:
> Back here in Scotland where I live, Polaris is at an altitude of 55 degrees
> (my latitude) and you just cannot get your eye behind the scope when it is
> cranked up at that angle. That is the limitation of the usual 'transit'
> type of theodolite, you are really limited to objects with altitudes of 40
> degrees or less for viewing that is comfortable, let alone possible. So
> called 'broken' theodolites like the Wild T4, where there is a right angle
> bend in the telescope, are what is really needed for celestial work. But
> the Wild T4 is accurate to a tenth of a second of arc and has a price tag
> to match - when they are available.

Another disadvantage is that the Wild T4 is very large and heavy (100
lb?). The comparable Kern DKM3A is marvelously compact and easy to
handle by one person. But it too costs thousands of dollars.

Right angle eyepieces for Wild theodolites appear on eBay occasionally,
but the bidding always goes high.

A dental mirror or similar small mirror can serve as a poor man's right
angle eyepiece. The field of view is restricted, but definition is good
at the crosshairs. On instruments with a microscope eyepiece (adjacent
to the telescope eyepiece) to view the circles, you have to be careful
to avoid reading mistakes with this method, since everything is reversed.

I think a small adjustable inspection mirror like this

http://www.grainger.com/product/PROTO-Inspection-Mirror-3R559?s_pp=false

could be attached to the telescope with rubber bands for hands-free
observation.

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