You jest! But I have thought about writing the penumbra widths for each time point on the dial face. (not on the actual dial but on a drawing or in list form) With a lot of work, it would be possible to do this, but would be of little or no practicle value in face layout. Would this be a penumbra width dial? (of course it would only be correct for two days of the year since the projection distance to a particular timepoint varies with the solar declination.
John John L. Carmichael Jr. Sundial Sculptures 925 E. Foothills Dr. Tucson Arizona 85718 USA Tel: 520-696-1709 Email: [EMAIL PROTECTED] Website: <http://www.sundialsculptures.com> ----- Original Message ----- From: "Mac Oglesby" <[EMAIL PROTECTED]> To: "John Carmichael" <[EMAIL PROTECTED]> Sent: Saturday, June 15, 2002 1:52 PM Subject: Re: Fabulous photos > > John, > > Thanks for the photos. Let's see---we have sundials, and we have > moondials. How about working on a lightening bolt dial in your spare > time? <G> > > Mac > > > > > > > >Hi Bob (and others): > > > >You must see these great photos (taken from postcards). One is a dramatic > >one-minute time exposure capturing multiple lightening bolts illuminating > >Kitt Peak. > >The other is an interesting double exposure, combining sunrise and > >mid-afternoon pictures of the McMath-Pierce Solar Facility. Hope nobody > >gets upset that I sent these unasked-for. > > > >Can you use these Bob? > > > >John > > > >John L. Carmichael Jr. > >Sundial Sculptures > >925 E. Foothills Dr. > >Tucson Arizona 85718 > >USA > > > >Tel: 520-696-1709 > >Email: [EMAIL PROTECTED] > >Website: <http://www.sundialsculptures.com> > > > >Attachment converted: Macintosh HD:Kitt Peak Lightning Time Exposu > >(JPEG/JVWR) (00046DFD) > >Attachment converted: Macintosh HD:McMath-Pierce Double Exposure.j > >(JPEG/JVWR) (00046DFE) > > -
