Quote:
Originally Posted by DavidU
Simon, in years gone past I have found that the secondary needs to be off set away from the focuser (as you have said) but also it needs to be moved towards the primary as well. If you draw the light cone to scale within a drawing of the OTA you will easly be able to measure these 2 off sets.
I also found that standard collimation techniques did not work with a very fast astrograph.
If you could give me all the measurements I can have a look for you.
Dave
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Thanks David, the Primary-Secondary offset was done correctly by the original builder, was only the Secondary-Focuser offset that was incorrect.
I have drilled the new holes, which also allowed me to correct one vane that was a bit askew.
Now to reposition the primary so I can achieve focus(there's an extra 8.5mm of light path, the Feathertouch focuser only has ~20mm travel) and then have another go at collimating with the Catseye's.
Fingers Crossed!