Monday, April 19, 2010

Palomar History Photo of the Week - April 19, 2010

Last week we showed you the 200-inch Pyrex disc as it arrived in Pasadena in April, 1936. This week's photo shows the face of the disc before the opticians had a chance to do their work.

As you can see in this picture from April 24, 1936 there were a number of large defects in the surface of the glass. It was the optician's job to grind past the surface defects before the process of placing the f/3.3 curve to the surface.

1 comment:

jay said...

What a great photo! It still has its lifting brackets from the train ride attached.