About to be a collectors item? Maybe not

My solar projector has been the best solar projector on the market but I have used up all the optical windows used to make the lenses and mirrors.  However I think I can make more lenses and if I can find a source of mirror I may offer these again.

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.

 

 

Advertisements

6 inch F/8 Chief

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.

 

6inchf8 220-250