At 08:25 AM 12/21/01 +1100, David Pratten wrote: >Dear Walter, > >Greetings. > >There is another factor which limits sundial accuracy to about +/-22 >seconds. This is the variation in the value of Equation of Time from >year to year within a leap cycle. See >www.sunlitdesign.com/infosearch/sundialaccuracy.htm
David and others, This might be true if the equation-of-time correction is obtained from a look-up table by date. But if the sundial includes the EoT correction in the shapes of its curves, or in the shape of the gnomon, the declination of the Sun is what controls the value of the correction being applied. In that case, I think the error would be *much* smaller than +/- 22 seconds. -- Roger
