NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Sundial
From: Gary LaPook
Date: 2016 May 2, 20:36 +0000
From: Frank Reed <NoReply_FrankReed@fer3.com>
To: garylapook@pacbell.net
Sent: Saturday, April 30, 2016 5:23 AM
Subject: [NavList] Re: Sundial
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From: Gary LaPook
Date: 2016 May 2, 20:36 +0000
Frank, I suppose that you have noticed that that large sundial mounted next to the Adler Planetarium in Chicago is off by several minutes even after accounting for its longitude and the equation of time. I was shocked when I found that considering that it must have cost a lot of money.
gl
From: Frank Reed <NoReply_FrankReed@fer3.com>
To: garylapook@pacbell.net
Sent: Saturday, April 30, 2016 5:23 AM
Subject: [NavList] Re: Sundial
That's awesome! There's a nice desktop software app called "Shadows" which you can download at shadowspro.com which will draw all those sundial lines for any combination of walls and angles you might desire. I also have a little analog projector I assembled that will 'paint' them on a wall (intended to be used at night). It's very simple in principle: you just project from the gnomon at 15° intervals.
So I'm up a little early today (early for me) because I'm teaching my "Sundials" workshop. You didn't know I was doing that today, right? Just one of those wild coincidences... After my alarm went off, I cleared my head and said to myself "time to think sundials!". Then I rolled over and checked my phone for NavList notifications. It said "Sundial" (your message). I had to check to make sure I was really awake. Ha! More later...
Frank Reed
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