After a long search I've found the frame field cobasis for all the time-like Schwarzschild geodesics. The third version of a write-up is here

Interference effects appear to be immune from some relativistic effects. One reason is that the phase difference between the emitter and receiver is a Lorentz scalar.

Here's a demonstration. Maybe even a proof.

http://www.blatword.co.uk/space-time/srphase.pdf

Some time ago I wrote a little program to convince myself of some home truths about SR. Mainly that doing Lorentz boosts leaves proper intervals unchanged. This program will boost any diagram you put in and calculate specified intervals. Of course they don't change, so this actually not necessary ( but the code does it anyway ).

The program is available here on a free non-commercial basis.

http://www.blatword.co.uk/space-time...wski_help.html

This...