Re: Hemicyclium correction - a figure might be needed

I can't find an image on the internet, of a Circumference-Aperture Cylinder-Equatorial dial, but I'm going to post a drawing of one. By the way, I use a broad definition of Equatorial Dial. Instead of only dials with a dial-face parallel to the equator, I include all dials that directly measure

Re: Hemicyclium correction

Correction: I'd said: (Tan dec)(R*2Sin(h) ). ...where h is the number hours from 12 noon.where R is the cylinder's radius. Here's the correction: Instead of "hours from 12 noon", It should say: "...where h is 15 degrees times the number of hours from 6 a.m., during the a.m. hours, or the

Re: Hemicyclium correction - a figure might be needed

gt; *From: *Michael Ossipoff <email9648...@gmail.com> > *Sent: *Tuesday, October 24, 2017 1:32 AM > *To: *Brad Thayer <wissenschaft...@verizon.net> > *Cc: *sundial list <sundial@uni-koeln.de> > *Subject: *Re: Hemicyclium correction > > > > > > In the Hemicycli

Re: Hemicyclium correction - a figure might be needed

> *Sent: *Tuesday, October 24, 2017 1:32 AM > *To: *Brad Thayer <wissenschaft...@verizon.net> > *Cc: *sundial list <sundial@uni-koeln.de> > *Subject: *Re: Hemicyclium correction > > > > > > In the Hemicyclium discussion, the OP mentioned having 6-inch copper >

Re: Hemicyclium correction - a figure might be needed

regards, > > Wojtek > > > > *From: *Michael Ossipoff <email9648...@gmail.com> > *Sent: *Tuesday, October 24, 2017 1:32 AM > *To: *Brad Thayer <wissenschaft...@verizon.net> > *Cc: *sundial list <sundial@uni-koeln.de> > *Subject: *Re: Hemicyclium correction

RE: Hemicyclium correction - a figure might be needed

, 2017 1:32 AM To: Brad Thayer Cc: sundial list Subject: Re: Hemicyclium correction In the Hemicyclium discussion, the OP mentioned having 6-inch copper tubing. So, though it was a bit off-topic, I suggested that the tubing could be used for an additional, quicker, project, to make a south

Re: Hemicyclium correction

In the Hemicyclium discussion, the OP mentioned having 6-inch copper tubing. So, though it was a bit off-topic, I suggested that the tubing could be used for an additional, quicker, project, to make a south windowsill sundial--a Circumference-Aprerture Cylindrical Equatorial Dial. But, when I

Re: Hemicyclium correction

I find the video below extremely instructive! https://youtu.be/0hs6QqwJIhs The sundial is marked in old temporary (or seasonal) hours. Changing them to modern hours does not make much sense to me. For it to become a hemicyclium I guess you just have to leave out the unused part of the

Re: Hemicyclium correction

@compuserve.com> > *Sent:* Sunday, October 22, 2017 12:40 PM > *To:* Brad Thayer <wissenschaft...@verizon.net> ; sundial@uni-koeln.de > *Subject:* Re: Hemicyclium correction > > Hi Brad > > Further to your interest in an hemicyclium you might like to know of this > link to

Re: Hemicyclium correction

today. My sincere apologies to Frans! Patrick From: Patrick Powers Sent: Sunday, October 22, 2017 12:40 PM To: Brad Thayer ; sundial@uni-koeln.de Subject: Re: Hemicyclium correction Hi Brad Further to your interest in an hemicyclium you might like to know of this link to the former webpages

Re: Hemicyclium correction

Hi Brad Further to your interest in an hemicyclium you might like to know of this link to the former webpages of the late Frans Maes who set out his instructions for “Construction of Hemispherium” some time ago and which is based on several earlier documents – all referenced. You might find

Re: Hemicyclium correction

gt; would seem it would be mathematically similar to a section of an armillary >> sphere. >> >> >> >> With a proper adjustable mount, I can adjust for the longitude correction >> (I am currently about 4 degrees away from my nearest meridian) and DST >>

Re: Hemicyclium correction

ection > (I am currently about 4 degrees away from my nearest meridian) and DST > twice a year as well. > > > > *From:* Michael Ossipoff [mailto:email9648...@gmail.com] > *Sent:* Tuesday, October 17, 2017 8:44 PM > *To:* Brad Thayer <wissenschaft...@verizon.net&g

Re: Hemicyclium correction

Just one safety quibble: If you mount the spike sticking up, then it will be an eye-hazard, even with the ball on its end. That's a good reason to mount the spike horizontally, at the rim of the bowl. It could be mounted in a north-south groove at the south side of the bowl. Mounting the spike

Re: Hemicyclium correction

Dear Brad, I'm delighted that you enjoyued my "tutorial"... > However, its your step 19 I am > interested in. Ah yes. That's where I mention marking out equal hours. I thought you would be most interested in that step :-) You add... > And if I do tilt the hemispherium > so that the horizon

Re: Hemicyclium correction

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

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> Subject: Re: Hemicyclium correction On Mon, Oct 16, 2017 at 8:48 AM, Brad Thayer <wissenschaft

RE: Hemicyclium correction

Subject: Re: Hemicyclium correction Dear Brad, You say: > I am looking to make a > hemicyclium-type sundial > (half-hemisphere) in a > metal working class. > Am I missing anything? Er, yes. Rather a lot alas... Before you start bashing metal it may be worth spending rather

Re: Hemicyclium correction

When I have a clock and not a sundial, clock time has to be converted into sundial time (Local True Solar Time) to make it day-relevant. So, if you make a sundial, shouldn't it just show sundial time? Isn't that really what a sundial for--showing Local True Solar Time? You could make a

Re: Hemicyclium correction

But, if you're willing to give up the Horizontal-Dial's advantages, then an Equatorial-Dial has the following advantages: 1. Its equally-spaced hour-lines allow perfectly accurate linear interpolation of the time, when the shadow is between hour-lines. (But, when usiing pocket horizontal

Re: Hemicyclium correction

On Mon, Oct 16, 2017 at 8:48 AM, Brad Thayer 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 being very clear on the problem. > But the way,

Re: Hemicyclium correction

Dear Brad, You say: > I am looking to make a > hemicyclium-type sundial > (half-hemisphere) in a > metal working class. > Am I missing anything? Er, yes. Rather a lot alas... Before you start bashing metal it may be worth spending rather less effort on a prototype. > ...they are