The projection distortion could be somewhat compensated by distorting the number cutouts, so the early and late hours are comparatively narrower.
Dave -----Original Message----- From: sundial [mailto:sundial-boun...@uni-koeln.de] On Behalf Of Fabio nonvedolora Sent: Friday, April 24, 2015 1:49 PM To: sundial@uni-koeln.de Subject: Re: A "Digital" Sundial on Instructables Hi all I think it can also work with a square section, so it should be easy to laser-cut. I also think the holes on the other side of every number may become a window, with inside frames, to allow a projection with any declination of the Sun (a bit more complicated) The problem may be the projection: the ratio between the size of the holes and the distance of the projection may blur it and it could become unreadable. ciao Fabio Fabio Savian fabio.sav...@nonvedolora.it www.nonvedolora.eu Paderno Dugnano, Milano, Italy 45° 34' 10'' N, 9° 10' 9'' E, GMT+1 (DST +2) -----Messaggio originale----- From: Richard Mallett Sent: Friday, April 24, 2015 10:01 PM To: Robert Kellogg ; sundial@uni-koeln.de Subject: Re: A "Digital" Sundial on Instructables On 24/04/2015 17:00, Robert Kellogg wrote: > Interesting digital dial. I must admit I looked at this design about 20 > years ago. The author has one 3D moveable drawing of the completed dial. > If you look closely on the underside of the gnomon, there are cut-outs of > hour numbers that match the obverse side. > > Therefore, this sundial works correctly only two days a year (I'm > inferring that the numbers were aligned for the equinox). Pity that such > a beautiful digital dial is nearly useless. Exactly the same problem with > Voshart's digital cube (see > http://gizmodo.com/this-digital-sundial-tracks-the-sun-through-a-laser-cut-1 545753402). > This may force me back to the drawing board since I hold US Patent > 5,596,5533 Jan 21 1997 "Digital Sundial". (See also Scharstein's US > Patent 5,590,093 Dec 31. 1996 "Digital Sundial". Dan's patent is earlier, > but he had to reference my article in NASS' Compendium). Ahhhh the modern > digital world. > > I understand that Apple's digital watches are being delivered to those few > lucky souls today. > --------------------------------------------------- > https://lists.uni-koeln.de/mailman/listinfo/sundial > > At a time when digital watches are hardly ever seen in the shops. -- -- Richard Mallett Eaton Bray, Dunstable South Beds. UK --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial
