My Smiling Red Face

[William S. Maddux]

 
John,
 
I am happy (though embarrassed) to report that I am now convinced
that most of the edge problems I saw in the proposal photos
were apparently artifacts.  They seem to have been 
introduced
into the PDF images by the compression/decompression 
processes.  
Perhaps some spatial periodicity aliasing was at work. There are 

suspiciously  moire-like patterns in panel areas, as well as less 
regular 
changes somehow introduced at the apparent edges.
 
However, this doesn't alter the bases for the calculation
of time-error vs edge-error that I posted on June 25th.
Photos did not enter into that:
 
>... Thus at that distance, the time required for the 1/2° degree 
>wide sun to pass through the meridian plane would be very 
>nearly 2 minutes of time during which it would move 
>about 9.3 inches relative to the style edge.  Therefore, if the 

>style's edge were to be laterally displaced 3 inches, the 
>resulting error in time would be about 3/9.3 x 120 = 38.7 seconds 

>of time, and a 1 inch wrong location of the effective edge would 
>cause nearly 13 seconds of error. ... .
 
which spoke to your comment: 
 
> .  By placing one eye at the base of a style, we could look 

>straight up the edge of the styles. We did see very slight 
>undulations in the styles, but we guesstimated that they were 
>only between I and 3 inches, a very small amount if you consider 
>the enormous size of the sundial. These could only affect the 
>precision of the dial by a few seconds.  Time will tell!
 
Indeed, time has already told me some things.
 
Continued best wishes for your endeavors,
 
Bill
 
 
 
 
 

Re: My Smiling Red Face

[John Carmichael]

Bill,
I'm happy that someone atempted an error analysis of the 
undulating styles.  I'll be most happy with the dial if time tells us that 
it is only 1 minute off.   But like Bob Hough told me yesterday: It is 
what it is.
 
The ridged areas on the panels are copper tubing with 
circulating cold antifreeze. These ridges don't affect the shadow edge at all 
because they lie below the styles.  The styles are three sided flanges 
that hold the side panels together. If you look very closely at the photograph 
of the East style, you will see that what I've been calling the East Style is 
actually two parallel styles separated by only about 6 inches.  Each corner 
of the flange is a style.  This creates an additional little style 
shift at High Noon because at High Noon, one style of the flange is 
directly above the other style.  At High Noon, the style shifts from the 
bottom flange corner to the top corner of the flange. But the since the 
distance  between the two styles is so small (6"), we saw no visible 
increase in the width of the penumbra.
 
We did see huge penumbra width changes within the space of 
about a minute when we had the big morning and afternoon shifts.  When 
these styles shifted the shadow velocity immediately changed and the spacing 
between the time points changes proportionately.
   
John
 
John L. Carmichael Jr.Sundial Sculptures925 E. 
Foothills Dr.Tucson Arizona 85718USA
 
Tel: 520-696-1709Email: [EMAIL PROTECTED]Website: 


  - Original Message - 
  From: 
  William S. 
  Maddux 
  To: sundial@rrz.uni-koeln.de 
  Sent: Wednesday, June 26, 2002 6:36 
  AM
  Subject: My Smiling Red Face
  
  
   
  John,
   
  I am happy (though embarrassed) to report that I am now convinced
  that most of the edge problems I saw in the proposal photos
  were apparently artifacts.  They seem to have been 
  introduced
  into the PDF images by the compression/decompression 
  processes.  
  Perhaps some spatial periodicity aliasing was at work. There are 
  
  suspiciously  moire-like patterns in panel areas, as well as less 
  regular 
  changes somehow introduced at the apparent edges.
   
  However, this doesn't alter the bases for the calculation
  of time-error vs edge-error that I posted on June 25th.
  Photos did not enter into that:
   
  >... Thus at that distance, the time required for the 1/2° degree 
  
  >wide sun to pass through the meridian plane would be very 
  >nearly 2 minutes of time during which it would move 
  >about 9.3 inches relative to the style edge.  Therefore, if the 
  
  >style's edge were to be laterally displaced 3 inches, the 
  >resulting error in time would be about 3/9.3 x 120 = 38.7 seconds 
  
  >of time, and a 1 inch wrong location of the effective edge would 
  
  >cause nearly 13 seconds of error. ... .
   
  which spoke to your comment: 
   
  > .  By placing one eye at the base of a style, we could look 
  
  >straight up the edge of the styles. We did see very slight 
  >undulations in the styles, but we guesstimated that they were 
  >only between I and 3 inches, a very small amount if you consider 
  
  >the enormous size of the sundial. These could only affect the 
  >precision of the dial by a few seconds.  Time will tell!
   
  Indeed, time has already told me some things.
   
  Continued best wishes for your endeavors,
   
  Bill
   
   
   
   
   

High Noon

[Mac Oglesby]

Now and then I run across the phrase "High Noon." Can someone please 
tell me what that means? I didn't find it in John Davis' excellent 
glossary.


Best wishes,

Mac Oglesby
-

Re: High Noon

[John Carmichael]

Mac

I thought we killed this cat already!  It's the time of the sun's transit
when it souths and is at its highest altitude during the day.

John

John L. Carmichael Jr.
Sundial Sculptures
925 E. Foothills Dr.
Tucson Arizona 85718
USA

Tel: 520-696-1709
Email: [EMAIL PROTECTED]
Website: 
- Original Message -
From: "Mac Oglesby" <[EMAIL PROTECTED]>
To: 
Sent: Wednesday, June 26, 2002 12:22 PM
Subject: High Noon


>
> Now and then I run across the phrase "High Noon." Can someone please
> tell me what that means? I didn't find it in John Davis' excellent
> glossary.
>
> Best wishes,
>
> Mac Oglesby
> -
>

-

Re: High Noon

[J. Tallman]

Mac Oglesby wrote:

> Now and then I run across the phrase "High Noon." Can someone please
> tell me what that means? I didn't find it in John Davis' excellent
> glossary.

Hi Mac,

I believe that term means the time of local meridian passage, when the
sun is at it's "highest"?

Jim Tallman



-

Re: High Noon

[MMB]

Mac Oglesby wrote:
> 
> Now and then I run across the phrase "High Noon." Can someone please
> tell me what that means? I didn't find it in John Davis' excellent
> glossary.


I can find no straightforward response. But try these.
Writers say:


"High noon has long been associated with a crisis or confrontation. The
classic western film of that name is not the origin, however. The term
has been used this way in English literature since the 14th century."

I have found online references to "high noon" referring specifically to
Midsummer's Day or St John's Day (24th June) when the sun is apparently
at the highest point for some days. (Druids, Masons).

The dictionary also says "high" has come to mean important as in "high priest".

Noon itself derives originally from "nine" or the ninth hour after
sunrise (probaby 3pm :-) and not when it is apparently highest in the sky.

Well...   you asked, Mac!

Maria Brandl
Mallacoota

37° 32' 60S
149° 45' 0E

-

Re: High Noon

[Ron Anthony]

>Noon itself derives originally from "nine" or the ninth hour after
>sunrise (probaby 3pm :-) and not when it is apparently highest in the sky.

Now isn't that interesting.  By coincidence or not, the noon hour on old 
Japanese dials and clocks is 9.  There are a couple of math models that explain 
this but the origin of this counting system is not known.

++ron


- Original Message - 
From: "MMB" <[EMAIL PROTECTED]>
To: 
Sent: Wednesday, June 26, 2002 3:30 PM
Subject: Re: High Noon


> 
> Mac Oglesby wrote:
> > 
> > Now and then I run across the phrase "High Noon." Can someone please
> > tell me what that means? I didn't find it in John Davis' excellent
> > glossary.
> 
> 
> I can find no straightforward response. But try these.
> Writers say:
> 
> 
> "High noon has long been associated with a crisis or confrontation. The
> classic western film of that name is not the origin, however. The term
> has been used this way in English literature since the 14th century."
> 
> I have found online references to "high noon" referring specifically to
> Midsummer's Day or St John's Day (24th June) when the sun is apparently
> at the highest point for some days. (Druids, Masons).
> 
> The dictionary also says "high" has come to mean important as in "high 
> priest".
> 
> Noon itself derives originally from "nine" or the ninth hour after
> sunrise (probaby 3pm :-) and not when it is apparently highest in the sky.
> 
> Well...   you asked, Mac!
> 
> Maria Brandl
> Mallacoota
> 
> 37° 32' 60S
> 149° 45' 0E
> 
> -

-