In message , Martin Brown
writes
Kay wrote:

Stewart Robert Hinsley writes

OTOH, for gardening purposes, the direction of the sun at midday is
probably close enough - unless you're setting up a sundial.
If you're setting up a sundial, isn't enough to wait till the sun
comes out, and then align it so it shows the correct time?

Only on two days a year (ignoring daylight saving time). It is a mild
irony that UK sundials are normally calibrated for GMT and either read
a hour out or have additional systematic errors in midsummer when we
have sunshine and use the garden more.

Otherwise it could read up to 30 minutes out of sync with reality. You
need to know the correction for apparent solar noon for your longitude
and date. The seasonal analemma curve is very beautiful.

http://solar-center.stanford.edu/art/analemma.html

Well made sundials have a small table of corrections or a devisouly
shaped gnomon to allow for this.

Regards,
Martin Brown

And presumably to take advantage of the deviously shaped gnomon have to
be precisely aligned?
--
Stewart Robert Hinsley