Re: light gathering vs diameter of reflecting spheres

[Robert Monaghan <rmonagha@xxxxxxxxxxxxxxxx>]

Spiratone made a 220 degree bird's eye lens for circa $20 US; it used a 
lens thread mount, clear plastic tube to hold an aluminized spheroidal 
surface, and a closeup diopter lens to bring it into focus. Folks 
suggested you could do the same thing with a +10 diopter lens, a silver 
xmas tree bulb (epoxied inside for strength?), and a clear PVC tube and 
broken out filter epoxied to the inside of the PVC tube. 

see http://www.tbk.de/news/birdeye1.htm for somewhat similar newer item
and http://www.smu.edu/~rmonagha/third/weird.html Wierd Lenses pages
and ~rmonagha/bronfe.html fisheye pages on related low cost options...

regards bobm


* Robert Monaghan POB752182 Dallas Tx 75275-2182 rmonagha@xxxxxxxxxxxxxxxx  *
* Third Party 35mm Lenses: http://www.smu.edu/~rmonagha/third/index.html    *
* Medium Format Cameras: http://www.smu.edu/~rmonagha/mf/index.html megasite*