PHi (1.618) is known as the golden rule
Example:
If your
Chandelier has a diameter of 18" (45.7cm)
take the 18" x 1.618 = 29" (73.6cm) ie 61.8% larger
The medallion
diameter is in the correct proportions
at 29"
(73.6cm)
Too Big ???
Now that
being said, if 29" is too big for the space
perform the
inverse calculation of the remainder of Phi
1- (.618) =
(.382) ie 38.2%
still keeping
within the Golden Rule of Phi
18" medallion
x 1.38 = a 25 inch medallion
No rules rule
so select 29", 25" or what ever matches your design
<= For more
read the article
Always
remember that when you view the medallion mounted on the
ceiling it
will appear much smaller from your perspective at a lower level.
By
selecting one that uses the golden rule calculation, it will appear
to
be the
right size with the correct visual distortion.