I was asked to give a talk at Stellafane July 22nd on the Chief and Jones medial among other things. I will also bring along my Chief and my medial refractor if I can get them packed into my car.
My solar projector has been the best solar projector on the market but there may be no more. I have used up all the optical windows used to make the lenses and mirrors and unless I can find an alternate source of optics my solar projectors are about to become collectors items.
A little history on these projectors. Back in the late 80s when I was working for US Precision Lens they were taking apart a TV projection lens and getting rid of a nice lens cell which I acquired. About the same time they were scrapping the optics for a mirror telephoto which had a nice 4.25 inch optical window. I edged some down to fit the lens cells and ground a nice long radius on them. I took them home and polished them on a LP66 lap on a polishing machine. At first I used 3.1 inch secondary mirrors from Coulter but later aluminized the windows.
I got a lot of compliments on the projector after the eclipse. I went to Tennessee to take these pictures.
Well that stinks, the 325 mm focal length lens was dropped from the available lens catalog so you can’t make the design I had posted here unless you make the lens. However there is one more 6 inch design that uses commercial lenses and hopefully they will still be available. I uses 220 and -250 mm lenses giving a little bit shorter BFL, a final F ratio of F/7.6 and a Strehl of .993.