Re: ATM A different telescope

[Hugues_Laroche@ses-astra.com]

You wrote:

> What I'm wondering is, has anyone looked at having
a fast spherical primary ( F1.5-2.0 ) and placing a smaller
convex mirror close to the focus to bounce the
image back to the primary such that it forms a
about f8 cone. I was wondering how good the
image would be at the final focus point if
some correction was done at this secondary.
For a Newton style, it would be 4 bounces,
for a camera, it would be 3.

Poor Dwight, I did not see any echo on your question.
I do not have alot of idea either, but.

I guess that if the final goal is a f8 system it is far
easier to do it from the start as is.

But, if one has an ultra-fast mirror, for example from
an unsuccesful other ATM attempt (hope I will not be
soon in the case :-( ), is it interesting?

About the optical quality: I wonder if the double reflection
on the spehrical primary does not partly cancel out the
spherical aberration? I assume the convex secondary
would have to be aspheric, and what about other aberrations?
Guess obstruction can be left to a relatively low value.

Any opinions?

Thanks, and clear skies!

Hugues