[AstralTraveller (David)]

Chris,

If you move straight from Sirius to Acrux the reading should be pretty close to right; the stars don't move far in 5 minutes. {As an aside to 'rider', on the scope I used to use the pointer moved with the rotation of the RA shaft. That way it was always right once you set it up at the beginning of the night. Don't modern mounts have some equivalent system?}

I note that when you move from Sirius to Acrux you travel 12 26 - 6 45 = 5h 41'. Now 00 15 - 6 45 = -6 30. So it may be that you have some scale a**e about. However I still can't explain the 00 49 discrepancy. Perhaps something grips or slips when it isn't supposed to.

You do have it aligned pretty right don't you? You can follow starts for 5-10 minutes just by moving the RA shaft?

If all else fails you can join us trogolites and just learn to star-hop .