Anyone have a good procedure to follow to collimate a refractor (5"
Meade APO)?

I have Meade's procedure and it is pretty useless. It is based on
creating a mask over the focuser with two holes in it at equal distance
and in a line, with both on one side of the center of the mask. Then,
with the lens cap on, install the mask over the focuser and shine a
flashlight thru the hole in the mask closest to the edge and look thru
the other hole, look for the image of three points of light reflecting
back off the lens cap and adjust the appropriate lens cell adjustment
screws to get the points of light to line up with the two holes in the
mask. You do this procedure in two axisis, horizontal and vertical.
After I did this, I had to really adjust it to get alignment in both
axis, and the resultant star test images got a lot worse with the
"comet" effect then I previously had. Meade then changed their mind and
said to do the procedure in the vertical axis only (in line with the
focuser rack) and forget about the other axis. Didn't sound right, but I
tried it, still no joy.

I have now put the cell adjustment as close to where it originally was
as I can get, but I am still getting some of the characteristic "comet"
effect with the stars that is indicative of off-collimation for a
refractor.

BTW, several star tests were done previously, diffraction rings were
clearer on one side of focus then the other. Very slight off center of
center rings, very difficult to see. Ronchi done at 120 and 150
lines/inch with no anomalies, looked real good. It is very difficult to
see the off center of the difraction rings

Here is my game plan for collimating this thing. Set the scope up, get
it in ggod focus on a good Mag 2 or 3 star at about 120X and just adjust
the screws until I can get the comet effect to disappear. Then go to
200x or greater and repeat. I think seeing the off-center of the
diffraction rings is too difficult and precludes doing this out of
focus. The comet tail is much easier to see.

Any coments??? Anyone have a better procedure, short of sending it down
to company 7? Also, if I do it my way, how should I shift the cell in
relation to the direction the comet tail is pointing, should I move the
cell in or out in that quadrant?

Thanks for any help!
m.

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