Re: Declination and Inclination

[Simon [illustratingshadows]

I am at a quick stop while on itinerary. Somewhere you have to address N and S 
as a basis for declination, ad then E or W. And somewhere you have the 
inclination. Thus there should be no confusion.

"S 45°W inclined 20°" for example. 

Chapter 18, pages 171 to 202 of Illustrating More Shadows discusses these dial 
types using several methods, and does a case study on such a garden dial.

So I guess I agree with most people, but the present of N or S, E or W, should 
remove any possible ambiguouity.

Simon

Simon Wheaton-Smith
www.illustratingshadows.com
Silver City, New Mexico W108.2 N32.75 and
Phoenix, Arizona, W112.1 N33.5


--- On Tue, 8/31/10, Frank King <frank.k...@cl.cam.ac.uk> wrote:

> From: Frank King <frank.k...@cl.cam.ac.uk>
> Subject: Re: Declination and Inclination
> To: "fer de vries" <ferdevr...@onsneteindhoven.nl>
> Cc: sundial@uni-koeln.de
> Date: Tuesday, August 31, 2010, 7:17 AM
> Dear Fer,
> 
> Thank you for your message.  Your procedure
> is almost exactly like mine.  I also start
> with the equatorial plane (I missed that
> step out in my message).  I then:
> 
>   1.  Rotate by phi (to make the plane vertical)
> 
>   2.  Rotate by Azimuth (to face the plane in
> the
>                
>           correct direction)
> 
>   3.  Rotate by inclination (to tilt it)
> 
> We differ at step 1 (you go 90-phi) but, for both
> of us, it is then "declination then inclination".
> 
> At step 2 we both rotate about a vertical axis
> but your axis is perpendicular to the plane
> (which is horizontal) whereas mine is IN the
> plane (because it is vertical).
> 
> For horizontal dials your method is clearly
> better because you stop at step 1!!
> 
> Best wishes,
> 
> Frank
> 
> ---------------------------------------------------
> https://lists.uni-koeln.de/mailman/listinfo/sundial
> 
> 

---------------------------------------------------
https://lists.uni-koeln.de/mailman/listinfo/sundial