Curiosity Dept: Ice sundial

2005-02-02 Thread David Pratten
Title: Message Dear All, Yesterday I was looking at the nice sharp shadowof an ice scupture about 3 foot high and I realised that it would be possible to make a sundial out of ice! Does anyone know if this has been done and are there any photos on the web? Thanks David

Analemma Photos article at Wired.com

2004-10-23 Thread David Pratten
Title: Message Dear All, Thought you may like this ... http://www.wired.com/news/technology/0,1282,65428,00.html David For sun related calculation needs ... visithttp://www.sunlitdesign.com/products/thesunapi/

RE: Precise EOT Program - Correction

2003-06-15 Thread David Pratten
Hello Gianni, Fer and John, Yes you are correct. December 22-23. I had another look at my spreadsheet and found that I had misread it. All the best David -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Gianni Ferrari Sent: Saturday, 14 June

RE: seeking for an azimuth software

2002-09-14 Thread David Pratten
Dear Alain, Check out www.sunlitdesign.com/products/thesunapi David -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Alain MORY Sent: Saturday, 14 September 2002 3:51 AM To: sundial@rrz.uni-koeln.de Subject: seeking for an azimuth software Hello !

Sundial Enthusiasts in Australia

2002-03-05 Thread David Pratten
Dear All, While I normally live in Kazakhstan, I am currently in Australia. I would love to hear (off list) from anyone in Australia with an interest in Sundials. You can email me at mailto:[EMAIL PROTECTED] or phone me in Sydney (02) 9585 2565 Thanks David Pratten www.sunlitdesign.com

RE: On northern vs. southern dials

2002-03-03 Thread David Pratten
Title: Message Dear All, I will take an intuitivepunt on any point on the arctic circle as having maximum ratio of southern exposure to northern exposure. Can't prove it. David -Original Message-From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Anselmo

RE: Polar ceiling sundial

2002-01-07 Thread David Pratten
The BSS sundial glossary has the following entry under Types of Dials: reflecting ~: these dials have no gnomon, but reflect sunlight by means of a semi-cylindrical mirror, set with the axis of the mirror parallel to the polar axis. The mirror reflects the light to form a caustic curve amongst

Refraction

2001-12-28 Thread David Pratten
Title: Message Dear Dialists, I have been pondering the effect of refraction on dial performance. Refraction quoted at .1 degree to .5 degree apparent difference in altitude below 10 degrees of altitude, will impact the hour angle to some degree. See

Did it pass unnoticed?

2001-12-24 Thread David Pratten
Title: Message Dear Dialists, Merry Christmas - and did it pass us unnoticed? Today at 2001/12/25 05:32:02 [UT] our dials and our watchesare running in synchronisation! David www.sunlitdesign.com

RE: accuracy

2001-12-20 Thread David Pratten
Dear Walter, Greetings. There is another factor which limits sundial accuracy to about +/-22 seconds. This is the variation in the value of Equation of Time from year to year within a leap cycle. See www.sunlitdesign.com/infosearch/sundialaccuracy.htm David www.sunlitdesign.com

RE: Query about solstices

2001-12-19 Thread David Pratten
Dear Fritz, Using Find Annual Feature function (sdxFindAnnFeatx)of the The SUN API www.sunlitdesign.com/products/thesunapi I get the follwing value for the solstice this December: December 21 19:21:30.7143 [UT] (which is +/- 10 seconds of the true value) Compare with

RE: Sundial link

2001-12-13 Thread David Pratten
Mounting the sundial upside down so that the face is oriented as for Britian will make the hour numbers go the right way ... David -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of The Shaws Sent: Wednesday, 12 December 2001 10:06 PM To: [EMAIL