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My VC200l was collimated as follows:
a friend turned up an adapter to screw a laser collimator directly to the focusing tube.
The secondary was completely removed (after carefully marking orientation and ensuring I did not lose the packing spacer between the secondary holder and the spider). The laser was then, after screwing in to the focuser tube, shone through the secondary support hole in the spider (a bit of tracing paper was fitted to the end of the scope to make the laser beam visible) - the focuser needed a tweak, enough to be noticeable,
The secondary was then replaced and adjusted such that the return beam hit the centre of the lasers 45 deg cutout.
This now means that the focuser and secondary are perfectly aligned. They should not need further work.
The primary can now be checked by looking up the focusing tube and centering the secondaries image by adjusting the primary.
Then look (easy with a ccd attached) at a centred defocused star - adjust until when the star is centred the rings are also centred.
At this point the scope has a roughly collimated primary and will still produce triangular stars.
According to CCD inspector the best I was ever able to get the primary using a star was to about 20 arc secs off line.
The using CCD inspector in collimation mode, adjust the primary progressively to improve collimation. You will find that once you hit about 3 ar secs of error, the triangular stars just disappear. Mine is collimated to about 1.8 arc secs, and stars are great right across the field. To get it this close you need to be adjusting the screws so that you are hardly moving them at all, otherwise they overshoot. Just lean on them....
This is the second VC200l I've had - I was an idiot and sold the first one - the current one ain't goin' nowhere!
If you get desperate, pm me and I'll lend you my laser adapter thingy and a collimated laser that is a heat fit to the adapter....
I also have an adapter for fitting a Takahashi collimation scope to the VC200l as well, though to use this fully the secondary mirror needs to be centre spotted - this needs a lathe to be accurate enough to use.
hope this helps,
cheers
Gary
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