[EMAIL PROTECTED] wrote: > > Hi All - > > I would like to set up a reflection dial (similar to the set up in "Sundials" > by Waugh) but have a couple of > problems and not sure if it is even feasable in my situation any help/comment > would be appreciated. > > The window(s) I have available are facing SSW (~220 deg.). I can get a nice > reflection on the ceiling BUT > here is the tricky part I would like to reflect the dial to a wall that is > facing NNW (~310-320 deg). > > My question/s - Is it possible to "double" reflect to the wall? And if there > is a way how would I go about it. > > Regards > Henry > In the Pacific NW (USA)
Hi Henry, This is an interesting problem which can be solved with my sundial program 'zonwvlak'. In America this program is for sale for a small price to members of the North American Sundial Society. To give a real answer to your question more information is needed. What is the latitude of the place of the sundial? What is the distance from the NNW wall to the first window in the SSW wall? What is the height of the NNW wall and the height of the point where the mirror will be placed? As an example I calculated for your window and wall and for a latitude of 45 degrees such a dial. The mirror is facing SE and has an angle of 45 degrees to the horizontal plane. The result is given in the attached gif picture. By variing the declination and inclination of the mirror other solutions are possible. You also see that the possible number of lines is limited. The SSW wall should be in the sun, the mirror should catch the sun and the light spot should fall on the NNW wall. And will the spot of light on the sundial be visible if the sun itself is shining on that wall? You can follow the suggestion of Chris Lusby Taylor, but then you need a year before the dial is finished. But it will be a nice experiment of course. Let us know if you are going on with this interesting project. Happy dialing, Fer de Vries, Netherlands. Attachment converted: MAC Hard Disk:mirror4.gif (GIFf/JVWR) (0000631E)
