Karl Schwarzinger's very nicely designed Analemmatic Sundial in Tyrol
(URL below) integrates both a raised and slopping platform to add some
compensation for height limitations in a larger sized dial. 

http://tirol-php.highway.telekom.at/k.schwarzinger/a_3500.htm

Cheers,

Luke


Steve Lelievre wrote:
> 
> John,
> 
> The NASS site has some DeltaCad macros.
> 
> As regards how big to make the dial, I suspect that people size will not be
> a meaningful starting point. In the extreme case, there is hardly any
> shadow.
> 
> Your dial is S.Calif - say about 33 and a bit degrees N. At the Summer
> solstice, the sun at noon is 23 and a bit degrees N, so the sun gets to
> within 10 degrees of being overhead. Thus a person of height 1.70m will cast
> a noon shadow of only 1.7m x tan(10), which is 30 cm. That's a 5 foot 7
> inches person giving a 1 foot shadow, in imperial units. Some men (including
> me!) and many women aren't that tall, so most users would have even shorter
> shadows. At other times of day and other times of year the problem would be
> less noticable, but I reckon that overall for that location the shadow often
> won't reach edge of a sizeable dial. So what I'm saying is that people will
> often have to make a imaginary line to the edge of the dial anyway to read
> the time, so why not just make the dial to suit the location and don't put
> lots of emphasis on getting the dial size to match shadow sizes.
> 
> I saw instructions for an Aussie analemmic dial which told users to clasp
> their hands together above their heads in order to lengthen their shadows.
> 
> Cheers, Steve

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