Astro-nut wrote:
In his 2001 presentation at Stellafane, Dr. Peter Chen shared the
results of the technology at that time. He was then working on a 52"
primary that weighed in at 27 pounds. Up to 50 mirrors could be made
between cleanings of the precision mandrils:

I presume the mandrils give you a mirror that is roughly the right
shape, then you have to figure it? They can't give you an accurate
figure without post-processing, can they?

Mike Maxwell