One problem I've personally encountered with a pointed post gnomon is that if the post's shadow falls too close to the foot of the post, the shadow of the tip may be lost in the shadow of the post's shoulder. This was on a vertical decliner.
Mac Oglesby http://www.sover.net/~oglesby/Gnomon%20Notes/GnomonShadows3.jpg --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial
