[raymo]

You work backwards Chris. If such a table existed, the max exposure I was getting with any given f/l lens at a particular declination with round stars, would tell me how far off I was,[by using the table] and whether further attempts to improve the alignment were sorely needed, or whether I was already close enough that any improvement would be minimal.
Even a table that gave figures for say 0-30-60 degrees declination and say
1-15-30minutes and 1 and 2 degrees inaccuracy would be of great benefit.
The figures would only need to be given for one lens length, say 50mm,
and one could easily extrapolate from that.

Unguided Ken.

Good idea Bill. There are tables of max exposures at different decs, with different f/l lenses, but are
for a stationary camera, not a tracking one.
raymo