1° Forum di Astronomia Amatoriale Italiano

[...]we often
get mirrors that are unusually smooth in the large scale surface.
And sometimes something else happens that I can't precisely
explain. It has to do with energy. Sometimes it feels like the
glass is sucking energy, and no matter how hard we work it we
can only make our tolerance (which is still beyond 50X per inch).
The glass can pass every test for anneal and homogeneity
with flying colors, but it still can be problematic for unknown
reasons. It seems to require all the energy we can produce, and
still wants more. But then sometimes with other mirrors it feels
like energy is -released- when we work it. After hundreds of
optics and dealing with customers, it seems that in some cases
this extra energy is attached to the customer. Its almost as if the
customer themselves had something to do with the outcome.
(Quantum physicists and/or students of Advaita will have to
address any further details on this subject, as its out of my
league to speculate any further). In the case of this mirror, it
just laid down very tight in the tolerance, and almost without
effort. The average measured RTA is comfortably less than 1/2
the airy disk. Its just one of those unusually remarkable mirrors,
technically speaking. (And we do like longer F/ratios. No doubt
about it.)

beh, potrebbe anche voler dire che se uno specchio è buono sulla carta ma poi all'atto pratico non è prestante, pazienza, è colpa del C del cliente

Infine a sorpresa se ne esce con l'osservazione che questa specie di energia spirituale che fa la differenza fra gli specchi, dipende dal cliente.
Un modo contorto ma, ammettiamolo, impeccabile, di dire la verita'.