Omegon AZ mount, Instruction Manual

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How to carry out the adjustment:
1. Insert the collimation eyepiece into the focuser. Alternatively, you can use a film canister with a central hole
as a home-made adjusting eyepiece. However, this will only allow very imprecise adjustment.
2. Look through the eyepiece. The secondary mirror of the telescope should appear round and centrally
positioned. If it does not appear circular, the large, central adjustment screw for the secondary mirror should
be adjusted until it does.
3. Now turn the three small secondary mirror adjustment screws, a little at a time, until the main mirror with
its three retaining clamps is seen to be centrally positioned in the secondary mirror.
4. The reflections of the adjusting eyepiece and the secondary mirror spider must be now be centred.
This is achieved using the main mirror adjustment screws. While looking through the adjusting eyepiece,
turn the adjustment screws and observe how the reflections move (you may need an assistant for this).
If the secondary mirror is now centrally positioned, the main mirror with its retaining clamps can be seen
and the secondary mirror spider is symmetrically placed in the centre, the telescope has been fully
adjusted.
Tip: Adjustment it easier to carry out if the main mirror has been given a centre marking. It is best to adjust
your telescope using a Cheshire collimating eyepiece or a collimating laser.
locking screw adjusting screw
secondary
mirror
primary mirror
both mirrors are
adjusted with the
collimation cap
both mirrors are adjusted
with the eye at the focuser