Re: Re:

Yes, please download. illustratingshadows.xls from Illustrating Shadows and look at some of the subsheets. Use the insert chart feature in excel. Look at my h-dial-analemma worksheet which uses Cartesian coordinates creating the familiar figure of 8. Warning... aspect ratio is not preserved,

Re: Looking for minutes and seconds correction for whole year for Equation of Time plaque

there are many excellent sources for that which you seek. my own offering would be my  illustratingshadows.xls on my Web site which has an astronomically appropriate worksheet, decimal lat and long are used, not minutes and seconds. And I have also averaged 4 years of them in supplemental

Re: PS: Looking for minutes and seconds correction for whole year for Equation of Time plaque

when I said supplementalShadows.pdf I meant to type  appendix-main-appendices.pdf sorry. However my averaging fir 4 years is avtually, now I look at it, in the Excel sheet  illustratingshadows.xls specifically the "astroEOT" sheet, however I did the averaging for mid month so as a turnkey it may

Re: Circular Spreadsheet Software

I would need more info. Freecad, Nanocad, Power draw are good 2fd cad ststems, programmable, and free. Power draw has no trig functions but I wrote some for it, see my website.  Illustrating Shadows | | | | || | | | | | Illustrating Shadows Material for sun dials,

Re: Circular Spreadsheet Software PS

I have given up on my Android spell check, sorry for typos. I am beginning to long for the days of the Creed 7B teleprinters, at least they didn't "correct" spelling. Simon  Sent from Yahoo Mail on Android On Fri, Jan 20, 2017 at 16:20, Steve Lelievre

Re: Astrolabes

I have two commercial planispheric astrolabes. The Norman Greene one in the puzzler link below looks as if it might not be accurate, however it is easy to read in full sun. Another I have is clearly more accurate but in full sun rather hard to read. Mr Morrison's work is definitive, excellent.

Re: Impact of making instruments out of boxwood

Box is also a preferred wood for end grain wood engraving, used for highly detailed images in books and magazine. Wood engraving on end grain has more definition than a woodcut which is in plank grain and does not tend to use box. Box is now somewhat expensive. SimonIllustrating Shadows | |