h from Az. Question about iterative solution of equations.

2015-03-21 Thread Michael Ossipoff
that their method compares well to other linear Regula Falsi methods. Michael Ossipoff --- https://lists.uni-koeln.de/mailman/listinfo/sundial

John Richard: h from Az, dec, Lat

2015-03-04 Thread Michael Ossipoff
is the azimuth circle passing through your desired azimuth, and solving for the h that would achieve that. If that's workable, then it could have the advantage that h only appears once in the altitude formula. I apologize in advance for any algebraic or copying errors. Michael Ossipoff

John Richard: h from Az, dec, Lat

2015-03-04 Thread Michael Ossipoff
Sorry, I accidentally wrote h = , when I meant sin h = , at the beginning of the formula for h, given Az, Lat, and dec. Michael Ossipoff --- https://lists.uni-koeln.de/mailman/listinfo/sundial

John Richard: h from Az, dec, Lat

2015-03-04 Thread Michael Ossipoff
I'm sorry--another typo: I meant to say: If your input azimuth is west of south, then h and its sine must be positive. If your input azimuth is east of south, then h and its sine must be negative I really didn't mean to post so much, but I wanted to correct those typos. Michael Ossipoff

John Richard: h from Az, dec, Lat

2015-03-04 Thread Michael Ossipoff
is clear. Ok, I don't think there will need to be any more fixes or corrections by me. Again, sorry about the omissions and typos, and the necessary corrections and fixes. Michael Ossipoff --- https://lists.uni-koeln.de/mailman/listinfo/sundial

Jack: Duration of sunlight on a particular day

2015-03-04 Thread Michael Ossipoff
corresponding to some particular value of dec, at some particular latitude Lat.* *And yes, _lots_ of people at this list know that. I'm not posting something new. But I just wanted to mention it because I haven't seen it in the answers so far.* *Michael Ossipoff

John Richard: h from Az, dec, Lat

2015-03-04 Thread Michael Ossipoff
won't be shaded by a building. Michael Ossipoff -- Richard Langley On Saturday, January 31, 2015, 31, at 11:05 AM, John Goodman wrote: * Dear dialists, * * Does anyone know a formula for calculating the hour angle given the azimuth, declination, and latitude? * * I’d like to know the time of day

Neater, briefer, presentaton of h solution, given Az, Lat, dec

2015-03-05 Thread Michael Ossipoff
. -- Michael Ossipoff If intened azimuth is north of the east-west line, then cos h tan dec --- https://lists.uni-koeln.de/mailman/listinfo/sundial

Does anyone have, or have access to, Compendium vol.12, #1, March 2005?

2015-04-12 Thread Michael Ossipoff
at that Compendium article, and tell me if it says anything that supports the abovequoted statements--and, if so,what it says? I'd appreciate it if you'd paste its words on that matter into a post here, or an e-mail to me ( at email9648...@gmail.com). thank you Michael Ossipoff ~ 26N, 80W

The other Mayall Mayall formula (in the wikipedi article notes) likewise gives the correct answer.

2015-04-06 Thread Michael Ossipoff
The other of the 2 Reclining-Declining formulas listed in the notes, at the bottom of the wikipedia Sundial article, likewise gives correct answers. Again, using: Lat = 51.5 Incline = 45 Decline direction = 45 degrees left of south ...The Mayall Mayall formula, in the article's notes, for

Mayall Mayall's Reclining-Declining formulas

2015-04-03 Thread Michael Ossipoff
changes or improvements to that Wikipedia article's Reclining-Declining section, or comment on it at that article's Talk page? Michael Ossipoff --- https://lists.uni-koeln.de/mailman/listinfo/sundial

Wikipedia says Mayall Mayall's, and Rorh's formulas are wrong.

2015-04-04 Thread Michael Ossipoff
previously published be at that introductory article? Michael Ossipoff --- https://lists.uni-koeln.de/mailman/listinfo/sundial

Mayall Mayall formulas are correct for a horizontal dial.

2015-04-04 Thread Michael Ossipoff
might mistakenly be judged as incorrect for that reason. Michael Ossipoff --- https://lists.uni-koeln.de/mailman/listinfo/sundial

Wikipedia says Mayall Mayall's, and Rorh's formulas are wrong.

2015-04-05 Thread Michael Ossipoff
Additionally, Mayall Mayall's formula (shown in the notes at the bottom of the wikipedia Sundial article) for the angle between the substyle and the line for noon, gives the right result for: Lat = 51.5 Inclination = 45 Declination = 45 degrees left of south Michael Ossipoff

Wikipedia says Mayall Mayall's, and Rorh's formulas are wrong.

2015-04-05 Thread Michael Ossipoff
I should add that the correct result described above, with Mayall Mayall's formula for the angle between the substyle and the line for noon, is gotten when the decline-direction (D) is measured from north. So D is the azimuth that the dial is facing. Michael Ossipoff

Wikipedia says Mayall Mayall's, and Rorh's formulas are wrong.

2015-04-08 Thread Michael Ossipoff
any statements without citation, but the abovequoted statement is in the wikipedia Sundial article without any citation. Evidently the wikipedist who re-posted that statemet wants the wikipedia Sundial article to remain a laughingstock. Michael Ossipoff ~ 26 N, 80W

Horizontally-Viewed, All-Day, All-Year, All-Viewing-Directions Dials

2015-05-20 Thread Michael Ossipoff
meet the requirements in this posting’s subject-line. Probably not, I guess. And, even if it could, it would probably require a novel, unfamiliar, complicated reading-method—unsuitable for a public dial. Michael Ossipoff --- https://lists.uni

Aurora, the beginning of the arrival of Dawn

2015-06-10 Thread Michael Ossipoff
. . …but would take longer to build than a plain 2-sided translucent Equatorial, or Vertical Declining, or Reclining-Declining dial. . Michael Ossipoff --- https://lists.uni-koeln.de/mailman/listinfo/sundial

Re: Fwd: Aurora, the beginning of the arrival of Dawn

2015-06-11 Thread Michael Ossipoff
Richard-- Thanks; that's in agreement with how we all perceive summer and winter. I'd say that the astronomers and the newscasters and radio-personalities should listen to the meteorologists. Thanks again Michael Ossipoff 26N, 80W On Thu, Jun 11, 2015 at 11:39 AM, Richard Mallett postmas

Can I share Universal Analemmatic Sundial image?

2015-07-02 Thread Michael Ossipoff
. Thanks to NASS and to Fred Sawyer for those images of the Universal Analemmatic sun-compass. Michael Ossipoff 26N, 80W --- https://lists.uni-koeln.de/mailman/listinfo/sundial

Re: Can I share Universal Analemmatic Sundial image?

2015-07-02 Thread Michael Ossipoff
a question and gotten an answer today. Michael Ossipoff Patrick-- Thanks for the reply. You wrote: Far better to contact the author, (or here NASS) to get permission for what you want to do [endquote] Yes, and that's what my posting was doing Though I didn't write directly to official NASS e-mail

Fwd: Aurora, the beginning of the arrival of Dawn

2015-06-11 Thread Michael Ossipoff
heard only good things about Australia and Scandinavia. Michael Ossipoff 26N, 80W - Reply message - Fra: John Pickard john.pick...@bigpond.com Til: sundial@uni-koeln.de sundial@uni-koeln.de Emne: Aurora, the beginning of the arrival of Dawn Dato: tor., juni 11, 2015 01:30 Hi

Fwd: Aurora, the beginning of the arrival of Dawn

2015-06-11 Thread Michael Ossipoff
the astronomers and the broadcasters who quote them) knows that, by the time June 21 arrives, it has already been summer for a long time. Michael Ossipoff 26N, 80W On Wed, Jun 10, 2015 at 7:30 PM, John Pickard john.pick...@bigpond.com wrote: Hi Michael, You are making life far too complicated

Re: A translucent sundial

2015-07-28 Thread Michael Ossipoff
. Michael Ossipoff On Tue, Jul 28, 2015 at 7:06 AM, Thibaud Taudin Chabot tcha...@dds.nl wrote: So it is actually the same as a window sundial but more or less in a horizontal position and doesn't project its hourlines on a surface to read time. At 12:47 28-7-2015, Robert Terwilliger wrote

Re: A translucent sundial

2015-07-28 Thread Michael Ossipoff
Accidentally omitted words: I meant to say, referring to the 2-sided Translucent Flat Dials, ...intended to be read from both sides, regardless of which side is illuminated. Michael Ossipoff On Tue, Jul 28, 2015 at 7:06 AM, Thibaud Taudin Chabot tcha...@dds.nl wrote: So it is actually

Re: Precision: the measure of all things

2015-07-28 Thread Michael Ossipoff
I should add: Didn't someone say that the oldest sundial known was a Chinese Equatorial Dial marked for Equal Hours? Anyway, in Europe, equal hours have been in use for, what, around 700 years? But, if I correctly remember what i read, Temporary Hours were in use in classical and ancient times,

Re: Precision: the measure of all things

2015-07-28 Thread Michael Ossipoff
, it seems to me that finding what percentage of the day is over, and how much or how little remains, seems a bit pessimistic, and maybe not a good way to name the time of day. ...but I realize that it had practical importance in agricultural societies. Michael Ossipoff On Mon, Jul 27, 2015 at 5

Re: Temporal Hours

2015-07-29 Thread Michael Ossipoff
accurate than water-clocks? Michael Ossipoff On Tue, Jul 28, 2015 at 11:58 PM, Roger Bailey rtbai...@telus.net wrote: Hi Michael and all, Temporal or Antique hours co-existed with equal hours from way back, thousands of years. It didn't take a technological device like a clock

Re: Temporal Hours

2015-07-30 Thread Michael Ossipoff
that that's a big disadvantage of Altitude Dials--their inaccuracy around noon, just the time when people would make lunch appointments. Michael Ossipoff --- https://lists.uni-koeln.de/mailman/listinfo/sundial

Another movie with a sundial

2015-07-17 Thread Michael Ossipoff
or ceased to shade the fishing-spot at a certain solar azimuth. Michael Ossipoff --- https://lists.uni-koeln.de/mailman/listinfo/sundial

Re: Tarzan's sundial

2015-07-18 Thread Michael Ossipoff
) 1959: Tarzan the Ape Man (Gordon Scott) Look at the synopses of those movies. Maybe one of them will have something familiar from the movie of interest. When you find the right one, or some possibilities for the right one, check to find out if it's on YouTube. Michael Ossipoff On Sat, Jul

Re: Tarzan's sundial

2015-07-19 Thread Michael Ossipoff
to multiply by sec Alt than to divide by cos Alt. sec Alt can be estimated directly from the shadow-casting object and its shadow, or it can be gotten from tan Alt, which might be easier to measure, or easier to judge directly from the object and its shadow. Michael Ossipoff On Sun, Jul 19, 2015 at 2

Re: Tarzan's sundial

2015-07-19 Thread Michael Ossipoff
. But, as an approximate measure of duration, where exact time-of-day isn’t needed, the method should be satisfactory anytime. Though I tested it a few times, I only actually *used* it on that one occasion at the beach. Michael Ossipoff 26N, 80W On Sun, Jul 19, 2015 at 12:32 PM, Barry

Time-Altitude method typo

2015-07-20 Thread Michael Ossipoff
on this street is south). Michael Ossipoff --- https://lists.uni-koeln.de/mailman/listinfo/sundial

Re: How wrong is your time zone: Map shows how far world clocks are from solar time

2015-10-25 Thread Michael Ossipoff
linked to, with the line-drawings and comments about a few map projections, the author of that didn’t even mention any elliptical projections. And, basically, he was just expressing his allegiance to current fashion. Michael Ossipoff On Sat, Oct 24, 2015 at 6:22 PM, Dan-George Uza <cerculd

Re: How wrong is your time zone: Map shows how far world clocks are from solar time

2015-10-25 Thread Michael Ossipoff
ed in 1805, by a teacher in Germany, and has been very popular. Michael Ossipoff On Sun, Oct 25, 2015 at 4:44 AM, Fabio nonvedolora < fabio.sav...@nonvedolora.it> wrote: > hi, I applied the same map on the globe. > [image: globe-Europe-400] > > ciao Fabio > > PS on reques

Re: Southern Hemisphere

2015-11-16 Thread Michael Ossipoff
Oops, a typo: I meant to say that, at the North Pole, no sundial will tell time when the solar declination is south. But, of course, at the South Pole, it's when the solar declination is *north*, that there won't be sunshine and sundials won't tell time. Michael Ossipoff On Mon, Nov 16, 2015

Re: Southern Hemisphere

2015-11-16 Thread Michael Ossipoff
tell time then. Michael Ossipoff 26N, 80W On Sun, Nov 15, 2015 at 5:37 PM, Phil Dorman <p...@wattagan.com> wrote: > Hi Everyone, > > > > I joined this list because I have a specific question which I can’t find a > definitive answer to. > > > > I want to ins

Re: due east

2015-09-16 Thread Michael Ossipoff
f due east. So: Say the edge of a distant telephone-pole is due-east from you. Starting out toward it, you're starting out traveling due eastward. But, after you've proceeded even a little way, continuing in that same straight line toward the telephone-pole edge, you'll soon be traveling i

Re: due east

2015-09-15 Thread Michael Ossipoff
quot;great circle". So, the paradox was just the result of two different meanings of "travel due-east". Michael Ossipoff On Tue, Sep 15, 2015 at 10:10 AM, Brent <bren...@verizon.net> wrote: > I'm confused maybe. > > I live in the northern hemishpere and anticipating

Re: Possible sundial in movie

2015-10-01 Thread Michael Ossipoff
on the hour-band. So I don't suppose that an armillary with an equatorial band would lose more than a few days of time-telling each year. Besides, maybe the upper part of the equatorial band is narrower than the lower part, as is sometimes the case. Michael Ossipoff > Speaking about sundials

Re: Romanian reclining sundial

2015-10-04 Thread Michael Ossipoff
, and that many sundials are marked in true solar time at the central meridian. Michael Ossipoff On Fri, Oct 2, 2015 at 6:12 AM, Willy Leenders <willy.leend...@telenet.be> wrote: > Dan, > > What I mean is this: > > 1. > Together with the sundial on the roof is given the EOT t

Re: Romanian reclining sundial

2015-10-04 Thread Michael Ossipoff
longitude west or east of the place's central meridian. Michael Ossipoff 26N, 80W On Sun, Oct 4, 2015 at 7:13 AM, Michael Ossipoff <email9648...@gmail.com> wrote: > > > On Thu, Oct 1, 2015 at 3:55 PM, Willy Leenders <willy.leend...@telenet.be> > wrote: > > >>

Re: Just the right spot and time!

2015-12-04 Thread Michael Ossipoff
The photographer must chosen in advance to take such a picture, and chosen the right time for the picture. Michael Ossipoff On Tue, Dec 1, 2015 at 9:11 AM, Dave Bell <db...@thebells.net> wrote: > Yes, the surprise is not so much that it happened, but that the > photographer was ther

Re: dodecahedron

2016-01-06 Thread Michael Ossipoff
as the whole cube is. Michael Ossipoff On Tue, Jan 5, 2016 at 11:46 PM, Roger Bailey <rtbai...@telus.net> wrote: > Thanks Fabio and Riccardo, > > This is really cool. It makes the design so easy, that it almost feels > like cheating. Consider the classic painting by Holbein

Re: It's still summer in Sydney (or is it?)

2016-04-06 Thread Michael Ossipoff
going to define 4 seasons, then March is part of Southern Hemisphere summer. December through March. But it would make even more sense to speak of March and September as 1-month seasons, as described above. Michael Ossipoff --- https://lists.un

Re: Re:

2017-01-22 Thread Michael Ossipoff
on with open office however because I once got malware from the > official site, not detected by the virus checker I used back then, which > was a top of the line. > > Simon > > www illustratingshadows . com > > > > > Sent from Yahoo Mail on Android > <https://over

Re:

2017-01-22 Thread Michael Ossipoff
I mean, just using Excel, without using VBA. Michael Ossipoff On Sun, Jan 22, 2017 at 11:45 AM, Michael Ossipoff <email9648...@gmail.com> wrote: > 1. I don't understand how a spreadsheet's rectangularly-arranged table of > values is a problem for designing circular things. The value

Re:

2017-01-22 Thread Michael Ossipoff
: Is it possible (without purchasing or downloading additional software) to print out graphics from Excel? ...to calculate, in Excel, co-ordinates of points along some curve, and then print-out the curve? ...useful for drawing a map, or a sundial, or any of lots of other things. Michael Ossipoff 2017-01-20

Re: Why we should reform the Calendar

2017-01-29 Thread Michael Ossipoff
year-rule allows the luxury of making our own choice of those two adjustment-parameters. This posting is already very long, and so I'll save the Minimum-Displacement leapyear-rule for a (immediately subsequent) next posting. Michael Ossipoff I seems to me that the March Equinox tropical year

Re: Why we should reform the Calendar

2017-01-29 Thread Michael Ossipoff
but it isn't necessary to base a calendar on a day that isn't today's mean solar day. Michael Ossipoff > Dennis and Ken, if you're listening to this discussion, please chime in. > > > On 1/29/2017 12:27 PM, sundial-requ...@uni-koeln.de wrote: > >> Send sundial mailing lis

Re: Why we should reform the Calendar

2017-01-29 Thread Michael Ossipoff
above. . ..and of course, any time when the current year is a leapyear, that fact will be amply announced long before the end of that year. Michael Ossipoff approx. 26N, 80W --- https://lists.uni-koeln.de/mailman/listinfo/sundial

Re: Why we should reform the Calendar

2017-01-28 Thread Michael Ossipoff
nciest leapyear system. I also propose a fancier, deluxely-adjustable system, but I won't try your patience with that here, because Nearest-Monday is entirely good enough, and is the system with obviously by far the best acceptance-potential. Michael Ossipoff. On Sat, Jan 28, 2017 at 3:38 PM, D

Re: Genuine or not?

2017-02-20 Thread Michael Ossipoff
for the latitude-marks on the inside of the vertical, piece--other than to make it look adjustable for latitude. Michael Ossipoff On Mon, Feb 20, 2017 at 9:57 AM, Dan-George Uza <cerculdest...@gmail.com> wrote: > Hello! > > There's a diptych sundial on sale for about 80 euros su

Re: Dial face colouration

2017-02-24 Thread Michael Ossipoff
onto the lamp-post. I'd consider declining-dials on the four faces, to that the shadow-casting edge would intersect the dial-face, on all four faces. Were pillar-dials usually, often, or ever made that way? Michael Ossipoff > > --- https://lists.uni-koeln.de/mailman/listinfo/sundial

Re: Dial face colouration

2017-02-25 Thread Michael Ossipoff
it allowed me to conveniently use a carbon-paper template that I'd prepared for drawing the hour-lines. Maybe the plain cardboard dial-face would have easier construction in one way, and less easy construction in another way. Maybe I tried one all-cardboard dial. It was a long time ago. Michael Ossip

Re: Dial face colouration

2017-03-01 Thread Michael Ossipoff
What am I saying?? You don't need the formula for the sun's brightness at different altitudes. You just need to tip the color-sample card, from the horizontal, toward the sun by an amount that's equal to the amount by which the summer-solstice deciination (23.44 degrees?) will be greater than

Re: Dial face colouration

2017-03-01 Thread Michael Ossipoff
that is bright enough when the sun is at its visible lowest at the dial-location, and still isn't too bright at solstice noon (on a horizontal dial). I'd bet that some brown or tan would be likely to meet both requirements. Michael Ossipoff On Tue, Feb 28, 2017 at 5:09 PM, Steve Lelievre

Re: Dial face colouration

2017-03-01 Thread Michael Ossipoff
it will be on the horizontal dial at summer solstice noon. (unless I've made another error) Michael Ossipoff On Wed, Mar 1, 2017 at 10:27 PM, Michael Ossipoff <email9648...@gmail.com> wrote: > What am I saying?? > > You don't need the formula for the sun's brightness at different alt

Re: First sundials

2016-12-15 Thread Michael Ossipoff
ound. Equatorial disk sundials supported by the disk and by the end of the gnomon on the ground are still in use. Michael Ossipoff On Thu, Nov 24, 2016 at 4:15 AM, Darek Oczki <dhar...@o2.pl> wrote: > Dear all > > I would like to ask your opinion on the first sundials which

Re: Precise locations

2016-12-26 Thread Michael Ossipoff
dn't it be good for people to be able to request that the square containing their front-door have the name of their house, if that word-combination (or something too close to it) isn't already in use? Thanks again. Michael Ossipoff On Mon, Dec 26, 2016 at 3:15 PM, Ian Maddocks <ia

Re: Precise locations

2016-12-26 Thread Michael Ossipoff
tude & longitude? ...or, if preferred, some widely-used plane-coordinate system? Michael Ossipoff On Sun, Oct 16, 2016 at 1:35 PM, Ian Maddocks <ian_maddo...@hotmail.com> wrote: > Hi Doug > > If you haven't been concentrating I added the W3W address to my signature > a few mo

Re: Capuchin and Regiomontanus dials

2017-05-14 Thread Michael Ossipoff
on the horizon, if the horizon is visible. A small paper tab, sliding on one of the edges, and casting an edge-shadow on a date-scale, gives a declination-reading that can be used to azimuth-orient the dial. Michael Ossipoff On Sun, May 14, 2017 at 5:18 PM, Fred Sawyer <fwsaw...@gmail.

Re: Capuchin and Regiomontanus dials

2017-05-14 Thread Michael Ossipoff
-motivated two-measurement method that I described above. Michael Ossipoff On Sat, May 13, 2017 at 9:23 PM, Michael Ossipoff <email9648...@gmail.com> wrote: > When I said that the vertical hour-lines should be drawn at distance, to > the left, from the middle vertical line, that is

Re: Capuchin Dials

2017-05-10 Thread Michael Ossipoff
Hi Peter-- Thanks for the reply and info. Yes, I hope that Fred Sawyer will post about the derivation of the construction of the Capuchin and Universal Capuchin dials. Fred, would you paste some of your lecture material, about that, into a list e-mail here? Michael Ossipoff On Wed, May 10

Re: Construction-Principle of Capuchin & Universal Capuchin Dials

2017-05-10 Thread Michael Ossipoff
a difficult explanation can give me a good hint, regarding the nature of where the construction came from. So thanks again for the help, the information, the links! Michael Ossipoff On Wed, May 10, 2017 at 4:56 PM, Yvon Massé <ymas...@wanadoo.fr> wrote: > Michael, > > Some years ago

Re:

2017-05-10 Thread Michael Ossipoff
Sure, analytic geometry verifies that the Universal Capuchin dial agrees with the formula that relates time, altitude, declination and latitude. But that isn't how medieval astronomers &/or dialists arrived at the construction of the Capuchin dials. Michael Ossipoff On Tue, May 9, 2017 at

Construction-Principle of Capuchin & Universal Capuchin Dials???

2017-05-09 Thread Michael Ossipoff
nstruction of a Capuchin or Universal Capuchin dial? Can anyone here explain that? If so, the explanation would be appreciated. Michael Ossipoff [image: Inline image 1] --- https://lists.uni-koeln.de/mailman/listinfo/sundial

Re:

2017-05-09 Thread Michael Ossipoff
the article to which I was referring. So my question is, "What would be a genuine explanation and justification for the construction of the Capuchin and Universal Capuchin dials? Michael Ossipoff 2017-05-09 15:49 GMT-04:00 Putowsky via sundial <sundial@uni-koeln.de>: > Diese Nachricht wurd

Re: Capuchin and Regiomontanus dials

2017-05-15 Thread Michael Ossipoff
. Michael Ossipoff On Mon, May 15, 2017 at 11:32 AM, Michael Ossipoff <email9648...@gmail.com> wrote: > Thanks for the Regiomontanus slide. > > Then the original designer of that dial must have just checked out the > result of that way of setting the bead, by doing the calculation

Re: Capuchin and Regiomontanus dials

2017-05-13 Thread Michael Ossipoff
ver the Shepard's dial, or the related Roman Flat altitude dial.) Michael Ossipoff On Sat, May 13, 2017 at 3:47 PM, Fred Sawyer <fwsaw...@gmail.com> wrote: > Take a look at A.W. Fuller's article Universal Rectilinear Dials in the > 1957 Mathematical Gazette. He says: > > &qu

Re: Capuchin and Regiomontanus dials

2017-05-13 Thread Michael Ossipoff
horizontal line, from the right edge to the point where the vertical line is drawn, is one unit. Michael Ossipoff On Sat, May 13, 2017 at 7:03 PM, Michael Ossipoff <email9648...@gmail.com> wrote: > Fred-- > > Thanks for your answer. I'll look for Fuller's article. > > One or twice,

Re: Capuchin and Regiomontanus dials

2017-05-15 Thread Michael Ossipoff
arrived at. So thanks for pointing out that natural approach, making choices than make more sense than the approach I was considering. Michael Ossipoff On Mon, May 15, 2017 at 2:54 PM, Geoff Thurston <thurs...@hornbeams.com> wrote: > Michael, > > I seem to recall that sec

Re: Capuchin and Regiomontanus dials

2017-05-15 Thread Michael Ossipoff
Of course, because only the four squared-terms are present, the two binomials have to be chosen so that, when they're both squared, their resulting middle terms cancel eachother out. (tan lat tan dec + 1) and (tan lat - tan dec) meet that requirement. Michael Ossipoff On Mon, May 15, 2017 at 9

Re: Capuchin and Regiomontanus dials

2017-05-15 Thread Michael Ossipoff
from being accurate. Michael Ossipoff On Sun, May 14, 2017 at 5:18 PM, Fred Sawyer <fwsaw...@gmail.com> wrote: > Michael, > > See the attached slide from my talk. All the various dials work with a > string of this length. They vary simply in where the suspension point is &

Re: Golden Ratio and Sundials

2017-06-21 Thread Michael Ossipoff
ph of something where do you put the > markers to make the measurement? > Along two mutually-perpendicular edges, measured from a common corner? :^) Michael Ossipoff > Brooke > Clarkehttp://www.PRC68.comhttp://www.end2partygovernment.com/2012Issues.html > > Origin

Re: Capuchin and Regiomontanus dials

2017-05-20 Thread Michael Ossipoff
ous suspension points were part of my > presentation. > What were some of the alternatives, and some of their relative advantages? Michael Ossipoff > > > Fred Sawyer > > > On Sun, May 14, 2017 at 4:40 PM, Michael Ossipoff <email9648...@gmail.com> > wrote: >

Re: Cast resin sundial

2017-06-06 Thread Michael Ossipoff
ve dials on its 4 vertical sides. Michael Ossipoff On Thu, May 25, 2017 at 1:30 PM, Dan-George Uza <cerculdest...@gmail.com> wrote: > Hello! > > I'm looking for advice on how to cast a sundial from epoxy resins, > specifically a cubical multiple sundial. Any ideas on how to go

Re: Cast resin sundial

2017-06-10 Thread Michael Ossipoff
dial-face. Michael Ossipoff On Tue, Jun 6, 2017 at 7:59 PM, Michael Ossipoff <email9648...@gmail.com> wrote: > Hi Dan-- > > I don't claim to have an answer to your question, because (evidently like > most) I don't know anything about casting resin. > > At least one 5-fac

Re: Hemicyclium correction

2017-10-18 Thread Michael Ossipoff
r bowl will have a cool ancient look when it weathers. Michael Ossipoff > > *From:* Michael Ossipoff [mailto:email9648...@gmail.com] > *Sent:* Tuesday, October 17, 2017 8:44 PM > *To:* Brad Thayer <wissenschaft...@verizon.net> > *Cc:* sundial list <sundial@uni-koeln.de>

Re: Hemicyclium correction

2017-10-17 Thread Michael Ossipoff
when adjusted for Equation-of-Time and for your longitude). I'd suggest changing your project to a garden-style Horizontal-Dial. Michael Ossipoff > > > --- https://lists.uni-koeln.de/mailman/listinfo/sundial

Re: Hemicyclium correction

2017-10-18 Thread Michael Ossipoff
way that a Disk-Equatorial does. ...but their dial-surface is parallel to the Earth's polar-axis so someone could argue that they should be called Polar Band or Cylinder dials. So what are they correctly called? Michael Ossipoff .. On Wed, Oct 18, 2017 at 3:29 AM, Nathaniel Shippen <shippenn..

Re: Hemicyclium correction

2017-10-17 Thread Michael Ossipoff
in the winter. Michael Ossipoff On Mon, Oct 16, 2017 at 8:48 AM, Brad Thayer <wissenschaft...@verizon.net> wrote: > I am looking to make a hemicyclium-type sundial (half-hemisphere) in a > metal working class. What little I can find on them says they are > inaccurate, without b

Re: Hemicyclium correction

2017-10-23 Thread Michael Ossipoff
, the drinking-cup would need a way of hanging it in the right orientation, and so it wouldn't be much like an ordinary drinking-cup. ...and the line-marking would be complicated by the non-cylindrical shape of the cup. Michael Ossipoff On Mon, Oct 16, 2017 at 8:48 AM, Brad Thayer <wissensch

Re: Hemicyclium correction

2017-10-19 Thread Michael Ossipoff
better of ancient realism. Besides, with the spike horizontal, its tip-nodus will still have a shadow that the spike itself doesn't get in the way of at equinox noon. Michael Ossipoff f . On Thu, Oct 19, 2017 at 11:13 AM, Frank King <f...@cl.cam.ac.uk> wrote: > Dear Brad, > >

Re: Hemicyclium correction

2017-10-19 Thread Michael Ossipoff
Of course, for the Cylinder Equatorial with circumference aperature, you could have declination-ilnes, which would be circles around the cylinder's circumference. Michael Ossipoff On Wed, Oct 18, 2017 at 10:23 PM, Brad Thayer <wissenschaft...@verizon.net> wrote: > Michael, > >

Re: Sundial books for children

2017-11-05 Thread Michael Ossipoff
someone's child is taking such courses. Michael Ossipoff On Sun, Nov 5, 2017 at 10:46 AM, Dan-George Uza <cerculdest...@gmail.com> wrote: > Hello, > > I am looking for titles of sundial books for children. I particularly > liked Annos sundial pop-up book by Mitsumasa Anno.

Re: Hemicyclium correction - a figure might be needed

2017-10-28 Thread Michael Ossipoff
Equatorial if it directly measures the Sun's apparent movement parallel to the equator, on a uniform circular scale that measures along a line parallel to the equator. ...even if the dial-face isn't parallel to the equator. Michael Ossipoff

Re: Hemicyclium correction

2017-10-25 Thread Michael Ossipoff
the a.m. hours, or the number of hours from 6 p.m., during the p.m. hours." ...which could also be said as: " 15 degrees times (6 minus the number of hours from 12 noon)". ...for the hours from 6 a.m. to 6 p.m. Michael Ossipoff On Mon, Oct 23, 2017 at 7:31 PM, Michael Ossipoff

Re: Hemicyclium correction - a figure might be needed

2017-10-24 Thread Michael Ossipoff
on the window-sill, of course the cylinder's inclination above the horizontal is easily adjusted by sliding the cylinder (or cone) northward or southward ...to incline the cylinder or cone with its axis parallel to the Earth's axis. Michael Ossipoff On Tue, Oct 24, 2017 at 4:33 AM, <wsga

Re: Hemicyclium correction - a figure might be needed

2017-10-24 Thread Michael Ossipoff
Typo: When I said: "So, in north declination, the south-notch would be used." ...I meant "*north*-notch". Michael Ossipoff On Tue, Oct 24, 2017 at 4:33 AM, <wsgalin...@gmail.com> wrote: > Thank you for your nice considerations. > > I think that some ki

Re: Hemicyclium correction - a figure might be needed

2017-10-24 Thread Michael Ossipoff
Another typo: When I said: "And in north declination, the circumference-aperture would be used." I mean that in *south* declination the circumference-aperature would be used. Michael Ossipoff On Tue, Oct 24, 2017 at 4:33 AM, <wsgalin...@gmail.com> wrote: > Than

Re: Hemicyclium correction

2017-10-19 Thread Michael Ossipoff
equal to the local latitude. ...and read the time from the hour-lines marked inside the cup. Obviously the circumference-aperature would limit how high you could fill the cup, when using it for drinking. Michael Ossipoff On Thu, Oct 19, 2017 at 2:31 PM, Michael Ossipoff <email9648...@gmail.

Re: Fwd: Re: The utility of sundials today.

2018-01-15 Thread Michael Ossipoff
That's true--A sundial shows things that a clock doesn't show, a direct showing of nature's day and year. Michael Ossipoff On Mon, Jan 15, 2018 at 2:55 AM, Kurt Niel <kepler...@gmail.com> wrote: > In some practical matter: > Using sundials you can: > - directly observe beha

Re: The utility of sundials today.

2018-01-14 Thread Michael Ossipoff
of whether there's practical need. Michael Ossipoff On Sun, Jan 14, 2018 at 2:26 PM, Willy Leenders <willy.leend...@telenet.be> wrote: > > When I talk about sundials, I get the question: "What utility can sundials > have today?" > In order to be able to give an answer as

This year a probe will be sent through the Sun's corona.

2018-02-08 Thread Michael Ossipoff
breeze is rustling the chlorophyll leaves of the green trees. So, with the warm sunshine warming your face, you say, “Ah yes, let’s intrusively experiment on the Sun, and dump garbage into it!” . Michael Ossipoff --- https://lists.uni-koeln.de

Re: This year a probe will be sent through the Sun's corona.

2018-02-09 Thread Michael Ossipoff
to me that the probe is much smaller than the Sun :D . II mentioned the matter here because people here probably aren't unanimously gung-ho about "anything for science". Michael Ossipoff On Fri, Feb 9, 2018 at 12:26 AM, Roger Bailey <rtbai...@telus.net> wrote: > Hel

Re: Lithuania wants to abolish DST

2017-12-22 Thread Michael Ossipoff
of getting hit by a car. In the morning dark, there are a lot fewer dangerous people out, as compared to evening dark. I suggest that every consideration points to leaving clocks on advanced-time all year. Michael Ossipoff On Fri, Dec 22, 2017 at 3:36 PM, Dan-George Uza <cerculdest...@gmail.

Re:

2018-08-10 Thread Michael Ossipoff
John-- But isn't it saids that Babylonian and Italian hour-lines are straight lines? Michael Ossipoff 2018-08-10 4:50 GMT-04:00 John Davis via sundial : > Diese Nachricht wurde eingewickelt um DMARC-kompatibel zu sein. Die > eigentliche Nachricht steht dadurch in einem Anhang. > >

Re: Dyptich sundial - help!

2018-08-10 Thread Michael Ossipoff
Sara and John-- But it's said that the hour-lines for Babylonian, Italian, and co-Italian hours are straight lines, as they are on all the other dials that I've seen that have Babylonian &/or Italian hours. Michael Ossipoff On Fri, Aug 10, 2018 at 4:37 PM, Schechner, Sara wrote: &g

  1   2   3   >