ATM A cage as secondary holder

[Marinus Lugt <Marinus.Lugt@dss.dornier.dasa.de>]

While considering alternative secondary holders I came up
with the following idea:

Inside the upper cage (of a truss tube design) a second cage
could be made. This second (inner) cage would be contained
within the outer cage. The outer cage would be connected with
truss poles, and support the focuser holder. The inner cage
would support the secondary holder (via a wire spider).
The inner cage would be mounted inside the outer cage such
that it would be possible to adjust it in all directions,
including rotation and tilt. (More or less like a 3-point
support for the primary)

I am thinking of the following advantages:
- The secondary holder itself would be really simple because
  it does not need adjustments screws (or the likes) this is
  especially usefull for secondaries < 1".
- Adjusting the collimation for the secondary can be done
  while looking through the eyepiece, and you do not need
  to reach inside the lightpath.
- The secondary holder could easily be made such that the
  secondary itself is replacable.

What do you think ?


Rien.