NavList:

Bear with me on what might be a dumb question.

With the Davis type ah, essentially a dish of water with wind shields, the instructions tell one to point the ah toward the sun so that the shadow is toward the observer, with no shadow along the side of the unit. With such positioning, proper orientation is obtained.

Using a mirror type ah, mirror mounted on a leveling plate arrangement of whatever sort one came up with, the thing would be oriented as above described. The mirror type ah would have to be leveled.

Shooting a star with a mirror ah, which has been mentioned I believe, one would "pre-calculate" the altitude and azimuth of the star, using a 2102-d or perhaps air navigation tables and point the ah down the appropriate compass heading, as there would be no shadow orientation possible. For a moon shot, location of the moon is obvious, and it's altitude can be roughly set on the sextant measuring with the height of one's fist at arms length, one fist equaling 10 degrees approximately.

Corrections please, if necessary.

Alan
----------------------------------------------------------------
NavList message boards and member settings: www.fer3.com/NavList
Members may optionally receive posts by email.
To cancel email delivery, send a message to NoMail[at]fer3.com
----------------------------------------------------------------