Re: Advice wanted, on 'Analemmatic' sundial orientation
Hi All, Good point of Fer de Vries. I have the following suggestions: - build a spider-sundial. You will have nice circles for the dates. The place you can stand as a human shadowcasting person can be on the path. If you place the majority of the hourlines and no horizon lines, the pattern is not visually related to the north. The marks for the date-circle can by on the path on the sunny southside . In this way I think the path can feel like the central axis of the dail. There is only 1 point where you can stand is a human gnomon. That is a small concession I think. - an other solution I thought of is one analemma on the path and 1 standing fixed gnomon beside the path. I we seek a bit I think that there is an analemma which is aligned with the path for 1 hour. Although you don't have a human shadow casting person, and there is only 1 hour marked, I think it will be nice and gives someone the feeling that the sun guides the path. Kind regards, Hendrik Hollander [EMAIL PROTECTED] www.analemma.biz lat 52 23' long 4 57' - Original Message - From: fer de vries [EMAIL PROTECTED] To: [EMAIL PROTECTED]; sundial@uni-koeln.de Sent: Wednesday, June 04, 2008 5:12 PM Subject: Re: Advice wanted, on 'Analemmatic' sundial orientation Alison, Well, you got a number of answers that it won't work, but Forget the analemmatic sundial and look for a shadowplane or hourplane sundial. Several of the wanted demands can be realized. It is an interactive dial, it has the hourpoints at the south side and the hourpoints can be in a circle. Have a look at our website: http://www.de-zonnewijzerkring.nl Work of members Archives 2003 Month 03-02 Best wishes, Fer. Fer J. de Vries De Zonnewijzerkring http://www.de-zonnewijzerkring.nl Molens http://www.collsemolen.dse.nl Eindhoven, Netherlands lat. 51:30 N long. 5:30 E - Original Message - From: Alison Shields [EMAIL PROTECTED] To: sundial@uni-koeln.de Sent: Tuesday, June 03, 2008 7:57 PM Subject: Advice wanted, on 'Analemmatic' sundial orientation Dear Sundial Experts, I have recently joined this Mailing List, and hope that any members will be able to give me some assistance on the following situation. Our local Stately Home (Kentwell Hall, Long Melford, Suffolk) is considering installing an Analemmatic sundial, as a new interactive attraction for visitors - but we are getting 'conflicting' advice, on whether this 'Human Sundial' will work in the way we want it to. We have been in discussion with Modern Sunclocks (apparently the acknowledged 'experts' for these features), who have told us that its central scale of dates must be aligned North/South - plus that hour markers must be correctly positioned on an elliptical ring, and which would lie on the Northern side of that scale of dates. Photographs on their website ( www.sunclocks.com ) confirm this. However, our 'Director of Operations' (Mr Phillips) absolutely INSISTS that he wants the scale to run exactly parallel with our main driveway - on a compass bearing which is about 162 degrees from North, with the hour points placed on its Southern side. He also wants the hour points to form an exact semi-circle, and not be elliptical in shape. Mr Phillips refuses to accept that he cannot arbitrarily position the Human Sundial feature as he wishes, and says that it must be possible to create this so that it could then align with the existing layout of buildings/paths. Can anyone on this Mailing List tell me whether it is possible to install a Human Sundial to fit any existing orientations, (with appropriate re-calculation of its component parts) - or, if not, just confirm that it must be as Modern Sunclocks have told me. I can then show the 'weight of evidence' to Mr Phillips. Because Kentwell Hall is a well-known Stately Home (open to the public), we should not want to become a 'laughing stock' by installing a feature which does not work - despite Mr Phillips assurance that all types of sundial can be adjusted to work, in any location. Looking forward to all comments (to this List, or sent privately). Sincerely, Alison Shields. --- https://lists.uni-koeln.de/mailman/listinfo/sundial --- https://lists.uni-koeln.de/mailman/listinfo/sundial --- https://lists.uni-koeln.de/mailman/listinfo/sundial
sundial - building integration
Dear fellow shadow-watchers, I am looking for some examples of sundials which are integrated with (public or private) buildings. Like the Walt Disney build for instance. Does anyone of you has some more examples for me? kind regards, Hendrik Hollander - Analemma Sundials H J Hollander Fixed +31 20 6374383 Cell +31 616 462 879 [EMAIL PROTECTED] www.analemma.biz lat 52 23' long 4 57' - --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: Hendrik Hollander Mean Time Dial
ith curved
declination lines when I was creating a very large sundial, not a
small one. Since the wavy irregularities show up only when you
zoom in and magnify the drawing, they are more visible on large
sundials not small ones. Does that make sense or am I not
understanding you?
But except for that wavy line problem,
I just want to say that I love the rest of Shadows Pro.When a
client comes to my studio, they love seeing the animated shadow
feature on my computer. I show them how the shadow will move
on their sundials before I make them. Also, I see that you
have incorporated Google Earth for finding latitudes and
longitudes. And there are many other nice little additions you
have made.
John
- Original Message -
From:
François Blateyron
To: fer de vries ; Sundial List
Cc: [EMAIL PROTECTED]
; [EMAIL PROTECTED]
Sent: Wednesday, August 16,
2006 10:51 AM
Subject: Re: ShadowsPro vs.
ZW DXFs
Hello all
In Shadows Pro, coordinates are
rounded to 1/10 of mm. This should be accurate enough for most
applications. But when you zoom a drawing you can see broken lines
as their ends are on a 0.1 mm grid. This is true with DXF and WMF
exported drawings.
The only case where the accuracy
could be a problem isif you draw a very small handheld
sundial.
This rounding operation comes from
early versions of Shadows and I will probably removeit in a
future version to avoid such aesthetic problems.
Regards
François Blateyron
www.shadowspro.com
- Original Message -
From:
fer de vries
To: Sundial List
Sent: Sunday, August 13,
2006 5:17 PM
Subject: Re: ShadowsPro vs.
ZW DXFs
John,Thanks for your examples that show the
differences in the sundial lines inseveral programs.It
is to my opinion a matter of number of points in a line and
roundingnumbers.If a sundial line is a straight
line, which is known of course, I calculatein ZW2000 only 2
points and by that in the computer the line also is
verystraight.A curved line is calculated as a series of
short lines and saved as a"polyline".In Autocad this is
a single line, in Deltacad however still a series ofshort
lines.In the Deltacad macro it is a "spline" which
perhaps is the best.You also can select it as a single
line.Has Deltacad an option to convert a series of short
lines into a "spline"?I couldn't find it, nor the word
"polyline".In ZW2000 a curved line can be calculated in
two accuracies.One point for every third day or for every
day.The default always is every third day. (Less points,
smaller file.)See option left down in the input
screen.Usual you don't need this extra option.Well,
any program has its own advantages and disadvantages by what
theprogrammer has choosen.The same is due for the Cad
programs you use.Best wishes, Fer.
Fer J. de Vries
De Zonnewijzerkringmailto:[EMAIL PROTECTED]http://www.de-zonnewijzerkring.nl
Eindhoven, Netherlandslat. 51:30
N long. 5:30 E
- Original Message -
From:
John Carmichael
To: Sundial List
Cc: François
BLATEYRON
Sent: Saturday, August
12, 2006 7:12 PM
Subject: ShadowsPro vs.
ZW DXFs
Hello all who use a CAD
program (cc. Francois Blatyeron):
I just noticed a big difference
in the sundial DXF drawingsproduced by Shadows Pro and
ZW2000.
When making a sundial
RE: Meridian alignments
The recent correspondence on meridian alignments has been interesting but I agree with Andrew James that the 'da Vinci code' should have the health warning. How far back do we wish to go with the situation regarding the 'prime meridian'? Since the time of Ptolemy (the Almagest man) and through the medieval period a large number of positions have been used by all sorts of authorities - nearly all somewhere in the Atlantic Ocean, going through the Canaries, various distances to the west of the Cape Verde Islands, etc. Popes have got involved, usually trying to satisfy the competing claims of Spain and Portugal. Map makers, like Mercator, and Sovereigns, for their own national ends, all chosing their own. The 1880 date quoted is wrong. The Washington Conference of October 1884 agreed that the Greenwich meridian would henceforth be the prime meridian with only San Domingo opposing and France and Brazil abstaining. The French still have what they regard(ed) as their prime meridian passing through the Paris Observatory the brass line is still inset in a room at first floor level. The St. Sulpice line is interesting, like others elsewhere on the continent and in Britain, but were largely laid down for other reasons. Tony Ashmore. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Andrew James Sent: 17 December 2004 10:40 To: Roger Bailey; f.pineau2; SUNDIAL LIST Subject: RE: alignment - Saint Sulpice I think perhaps the double use of the word meridian lies at the root of this confusion. From its antecedent word meridies - the middle of the day - we see how it means a line for determining time of noon and that is local noon wherever it may be situated, be it Saint Sulpice, Bologna, or Durham. The use of a particular line of longitude where the Sun is at its highest, noon, at the same time, as a base for measurement or prime meridian is another matter, for that could be done without reference to the Sun at all, for example with the required North - South line being established by the stars from any suitably equipped place - London, Paris, Rome, Palermo ... In this day and age perhaps The Da Vinci Code should have a very big notice on the cover warning that it is not entirely composed of verifiable facts! The curious thing is that (as I understand) there are already many books commenting on it and many reviewers - let alone members of the public - seem to accept its allegedly historical background and interpretations as more or less scholarly truth, however poorly they may stand up to scrutiny. I am sure, Roger, that you are not the only one to be confused by it but at least you can recognise an embellishment! Andrew James Roger Bailey wrote: snip The Saint-Surplice meridian is a key element in the best selling novel The Da Vinci Code by Dan Brown. snip This confused me as I expected the Paris Meridian to go through the Observatory of Paris ... The meridians are quite different but the novel brings them together. This is not the only fact embellished by the author to set the plot for his novel. PRI Limited, PRI House, Moorside Road Winchester, Hampshire SO23 7RX United Kingdom Tel: +44 (0) 1962 840048 Fax: +44 (0) 1962 841046 www.pri.co.uk The Intelligent Metering Company This correspondence is confidential and is solely for the intended recipient(s). If you are not the intended recipient, you must not use, disclose, copy, distribute or retain this message or any part of it. If you are not the intended recipient please delete this correspondence from your system and notify the sender immediately. This message has been scanned for viruses by MailControl -
Re: The Henley Hall Dial
Hello John, I don't think me E-mail of the 12th got through so I will repeat it. I live just about 12 miles from Bitterley where Henley Hall is located. If you could give me some details of what I am looking for I will call down there and take some photographs. Silas Higgon. - Original Message - From: John Carmichael To: Sundial List Sent: Sunday, October 10, 2004 4:00 PM Subject: The Henley Hall Dial John Davis found out that Victorian The Henley Hall dial was last seen by Chris Daniel at Henley Hall in Ludlow Shropshire (not Suffolk as I had said earlier)). I don't have a street address, but we think it's still there. So if anybody lives near Ludlow, we'd love to get some new photos of it. Thanks, John p.s. Please excuse me for not mentioning that the Behrendt article PDF link was so big!
Re: Roman Numerals - as a test message
Further to Andrew James message on Roman Striking on Clocks, the saving on the number of striking blows is much greater than perhaps some non-clockies might appreciate, as Andrew just drew attention to the two blows saved at 4 o'clock. At 12 only 4 strokes are needed instead of 12, 3 at 11, 2 at 10, 3 at 9 and so on. This means that only 30 strokes are required in 12 hours in place of the usual 78, a considerable saving for, as Andrew said, long duration clocks. Tony Ashmore. N 51 28 W 1 04 -
Re: New Sundial books?
Claude, A very useful book is PRACTICAL ASTRONOMY: A User-friendly Handbook for Skywatchers, by H. Robert Mills and published by Albion Publishing of Chichester, Sussex, England. ISBN 1-898563-02-0 (hardback) or 1-898563-00-4 (paperback). Reprinted 2000. Don't be put off by the title. It is wide ranging but Chapter 2, (The Sun and Sundials) covers various sundial designs and shows how to make them using card, sticks, string and such like. It has a fair amount of mathematics but the author wrote it with the pocket calculator in mind. Beware of some rather odd type-setting in places! Hope you find it useful. Tony Ashmore. - Original Message - From: Claude Hartman [EMAIL PROTECTED] To: sundial@rrz.uni-koeln.de Sent: Monday, October 13, 2003 6:56 PM Subject: New Sundial books? Hi dialists! Does anyone know of a book written for beginning dialists that uses hand calculators? The most widely available books here in the U.S. seems to be those of Waugh and of the Mayalls. To use a calculator with Waugh requires translating all the logarithm formulas. Mayall puts all the formulas in the back of the book. Both books make such an extensive use of plotting diagrams that the calculation seems a secondary method. The excellent book by Rene Rohr also makes use of mathematical calculation as a secondary technique. I am looking for recommendations for the beginner for my Back to Basics column in the NASS Compendium. Claude Hartman - -
Re: Sundials in Manchester of all places
Ian Maddocks wrote, in his interesting description of the Manchester exhibition, that the proposed Cornbrook device was a sundial based on an 'entropy surface'. One non-mathematical definition of entropy is 'a measure of disorder'. It would appear that the originator has chosen a most apt statement about his design! It would also appear that several others also have the same derivation. Tony Ashmore. 4 Cornbrook A bit on the confusing side: a sundial based on an entropy surface. Cornbrook is a station on the Manchester tram system but is a high level interchange only station with no street access. The point of this sundial is to provide something which connects the walkers walking past on the canal bank with the trammers on the platform. The dial itself is a large swooping thing from next to the platform to down by the path where it has some seats built in. There were plenty of slats designed to produce light/shadow at 5 and 12 minute intervals (the frequency of the tram services on the 2 lines). I didn't get the half of this frankly -
Re: New to sundials; interested in heliochronometers
Hello Jon, Mike Shaw wrote: I do have one non-interactive one - an equinoctial made by Silas Higgon. It uses two interchangeable specially shaped gnomons, one for use when the sun is travelling south, and the other for when it is heading back in my direction. Adjustment is required on four days a year - at each solstice, and when the clocks change. It's not too onerous. As a rider to this you can, I believe, use only one gnomon and move the dial band at the solstices. You can then read the leading edge of the shadow during the time the sun is declining and the trailing edge when the sun is heading Mike's way once more. There will be a small error in only using one gnomon but no more than about 3 minutes which, I think, is quite acceptable. I hope to be making one soon for Singapore where there is no summer time to further complicate things. Silas Higgon www.sun-dials.net - Original Message - From: Jon Noring [EMAIL PROTECTED] To: sundial@rrz.uni-koeln.de Sent: Wednesday, October 16, 2002 5:53 AM Subject: New to sundials; interested in heliochronometers Hello, For a while I've had an interest in sundials, but never explored that interest in any detail. I recently decided to study it more closely, at least whatever web-based resources I could locate. It is certainly a fascinating topic -- and for some a real hobby to collect and/or build sundials. Having a substantial solar energy RD background (e.g., in the 1980's I worked on solar central receiver power systems while at Sandia), I can say that I actually understand (even after all these years) the astronomical basis of the equations governing the position of the sun in the sky, the Equation of Time (EoT), etc., and how to apply them for terrestrial systems (e.g., solar central receiver systems must know the precise location of the sun for directing the position of the steerable heliostat mirrors.) Also, having a mechanical engineering background, one can say I am a fanatic (read: anal) on accuracy and precision. Thus, I have a stong interest in sundials which can determine standard and/or local solar time down to a minute or two (I believe these sundials are termed heliochronometers, am I right?) Doing a search, one intriguing (and surprisingly simple) design of a heliochronometer is that built today by John Gunning (who I would not be surprised is a member of this mailing list). For the very few here who have not yet seen his web site, go to: http://www.dbweb.com/gunning.sundials/ Two more interesting heliochronometers are those made by Precision Sundials: the Renaissance and the Sawyer Equant. See: http://www.precisionsundials.com/ I'd like to know of other designs for heliochronometers, historical and current. And I'm especially intrigued to know of designs that do not require any alignment interaction nor adding or subtracting minutes to compensate for the EoT (the heliochronometers mentioned above are interactive, if I have that terminology right), and those which use shadowing (besides the Sawyer Equant) rather than projection of the solar disc using a pinhole (the Gunning) or using a mirror/prism (the Renaissance.) (On a related topic, I assume a truly non-interactive heliochronometer -- just look and read -- would have to come in two parts to cover the two six month periods between solstices in order to compensate for the variable EoT between the two periods -- literally two sundials rather than one. In the deepest sense, therefore, there appears to be no such thing as a truly non-interactive heliochronometer for year- round use since one would at least need to know the month or season to pick the right scale or sundial to use! -- definitely a form of interaction. So what I term a non-interactive heliochronometer would require one to at least know the season and accordingly pick the right scale to read. Am I right here?) Anyway, I'd also like to know what books on sundials have very good coverage of the history and design of heliochronometers. I have more questions, but will consider asking them at a future time. I don't wish my introductory post to overwhelm the reader any more than it must have already. Thanks! Jon Noring - -
Re: BSS Newbury Meeting
David, Could you supply me with directions for 28th please. Silas. - Original Message - From: [EMAIL PROTECTED] To: sundial@rrz.uni-koeln.de Sent: Tuesday, September 17, 2002 9:49 AM Subject: BSS Newbury Meeting The British Sundial Society One Day Meeting at Newbury UK. 28 September 2002. Very interesting informal gathering, open to BSS members and non-members. Members / visitors displays of Sundial related items. Short ten minute talks on a range of subjects. Ample time for friendly chats among likeminded folk. It really truly is a most enjoyable day whatever your interests. Special this year, the largest display of WW2 Astro Compasses and related documentation. Bring along your Astro Compass, etc., ( name label ) and see all the various models made. Bring your own picnic lunch, soft and hot drinks provided. £8 per head admission. Free parking. Open 9 am to 5 pm. Come any time. Contact me off list for location details. David Pawley. The British Sundial Society One Day Meeting at Newbury UK. 28 September 2002. Very interesting informal gathering, open to non-members. Members / visitors displays of Sundial related items. Short ten minute talks on a range of subjects. Ample time for friendly chats among likeminded folk. It really truly is a most enjoyable day whatever your interests. Special this year, the largest display of Astro Compasses and related documentation. Bring along your Astro Compass, ( name label ) and see all the various models made. Bring your own picnic lunch, soft and hot drinks provided. £8 per head admission. Free parking. Open 9 am to 5 pm. Come any time. Contact me off list for location details. David Pawley. ___ Freeserve AnyTime, only £13.99 per month with one month's FREE trial! For more information visit http://www.freeserve.com/time/ or call free on 0800 970 8890 - -
that quotation again.
Hello All, I think Tony's remarks about the dialmay be correct and all the gnomons of these ancient(!) dials may be held by Whitworth threaded screws! The earliest date from Patrick was 1640 but Richard gives us a date of 1882 for the publication of the book. David reinforces this with his attachment from the Gatty book and it may be that the earliest dial with this motto is, in fact, 1892. Where do we go from here, I wonder? Silas. Lat 52.5 long. 2.8W
quotation
Thanks to everyone for their help with the quotationand treble thanks to you, Patrick! Silas.
Quotation?
Hello All, Is anyone aquainted with the following quotation seen on a dial of 1703 madeby Henry Thomas? "Amyddst ye flowres I tell ye houres Tyme wanes awaye as flowres decaye Beyond ye tombe fresh flowers bloome Soe man shall ryse aboe ye skyes" Does anyone know the source of this please? Silas Higgon. Lat 52.5 Long 2.8W
Re: time scale labels
Hello Jim, To differentiate between the two scales perhaps you could use roman numerals for one and arabic for the other. Also, may I suggest that instead of putting them one above the other that you put one "inside" the other so that they appear to be side by side. Perhaps you could separate them by a continuous double line? As John has said, I don't think it matters whether you call them summer time or DST etc. but you would need an EoT curve either on the dial plate or, more conveniently, on a small plate at head height. Regards, Silas Higgon (Connoisseur Sun Dials) - Original Message - From: J.Tallman To: Sundial List Sent: Thursday, July 18, 2002 3:56 PM Subject: time scale labels Hello All, I have been working on a vertical sundial and I have a question. This South facingvertical has two time scales on it, one at the top that shows thehour numbers to use during the period of the year when Standard time is in effect, and one at the bottom to show the hour numbers to use during the Summer when Daylight Saving time is in effect. The hourlines will include the appropriatelongitude correction for the site. There is also a completeEoT chart located right under the shadowfield on the face of the dialplate. My question is whether or not it would beacceptable to actuallylabel each scale "Standard Time" or "Daylight Saving Time"so that casualobservers wouldbe able to tellwhich one to use for the appropriate time of the year. My understanding is that there are threethings to consider when designing a dial that will indicate StandardTime: solar time at the reference meridian, longitude correction, and EoT. Since all three of these things will be dealt with on the dial face, would it be appropriate to label the time scales? One of my good sundial friends has commented that technicallythe scales do not really indicate true Standard Time/DST because the EoT is not actually computed into the hourlines. I would be interested to hear what the consensus is regarding this issue, because I want to do the right thing. If theseexact titles are objectionable does anyone have any ideas what I might use for alternative labels? Iam trying to make a dial that is easyfor"regular people" tounderstand and use, and I think some kind of label along the time scales would be helpful to casual observers. Regards, Jim Tallman Sr. Designer FX Studios 513.829.1888
Re: New Deltacad Macro
Would it help if I were to send you art-work for the finger plates? Silas. - Original Message - From: fer j. de vries [EMAIL PROTECTED] To: sundial sundial@rrz.uni-koeln.de Sent: Thursday, April 18, 2002 9:11 PM Subject: New Deltacad Macro Hello Diallists, It's about two years ago I made some Deltacad macro's to draw horizontal analemmatic sundials. It also was meant to show how to use Deltacad for sundials. Recently John Carmichael asked for an improvement of this macro. His whish was to add points for half hours and so on. It was rather easy to do, so I added some statements and the macro Analem3 now is able to draw half hour points, quarter hour points and 10 minutes points. ( I named this last option 1/6 hours in the program) One version of the added macro's just draws the dial, the second version also writes a textfile Analem3.txt in which you may find the coordinates of all the points. The two files are zipped in one flie of only 8 kB so I just attach it to this mail. Have fun with it. Best wishes, Fer. Fer J. de Vries mailto:[EMAIL PROTECTED] http://www.iae.nl/users/ferdv/ Eindhoven, Netherlands lat. 51:30 N long. 5:30 E -
Re: Sundial Restoration
Hello Phill, This message arrived for me by mistake. Thought you might wish to know. Silas.
Coles sun compass
Dear friends, An expatriateliving in the Middle East is trying to buy a Coles Sun Compass or its American equivalent. Can anyone please help? Silas Higgon.
MEAN TIME AZIMUTH DIAL
Hello All, For some time now I have been working on a mean-time dial using the suns azimuth. I have made a quarter scale model and have posted some images and a description on my website www.sun-dials.net. If you go to WHAT'S NEW there is a link to AZIMUTH DIAL at the foot of the page. If an organisation would be interested in such a dial I would willingly give my design services free. Silas Higgon.
