If the manufacturing for the 2.4 meter mirrors existed a decade earlier, and Hubble used the existing processes, does that mean all the KH-11 satellites also have the spherical aberration problem that Hubble has?
The spherical aberration of Hubble's main mirror was caused by a manufacturing defect.
Perkin-Elmer designed a new null corrector to verify that the mirror was made to spec, but the null corrector was incorrectly assembled (one of the lenses was out by a few mm). They also used the previous null corrector to test, which showed that the mirror was incorrectly ground, but decided that the new null corrector's measurements was correct.
But wouldn't they have needed to do that for KH satellites too? If they're making new equipment and processes, they'll be saving a lot less money from using KH mirrors
It was a new piece of test/validation equipment used on Hubble first. Reread it, they used the new equipment to test Hubble that had an error during assembly, they also crosschecked against the old machine which showed the mirror was flawed, and incorrectly decided that the newer machine was correct when it passed the Hubble mirror.
The test equipment is a much smaller part of the cost than developing, building and testing the machines required to actually grind the mirrors to spec in the first place.
or hubble has the aberration because the design optimized for cost on that bandwidth, because nobody would ever need to zoom individual fibers on a newspaper page? remember those where pointed the other way around.
but that's an awesome rabbit hole you pointed out!
