Quote:
Originally Posted by leinad
Collimation was ok, but I feel the secondary mirror needs to turn clockwise so that the sec. mirror reflection is centered in the focuser circle.
I'm a bit scared of touching the sec. mirror as yet and not sure how to do this.
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Don't be worried about adjusting the secondary. With no eyepiece/tool in the focusser, reach in with your left hand and practice getting a grip on the secondary mirror holder without allowing your fingers to touch the mirror surface. With the focusser empty, you can see where your fingers are, to get a feel of what you need to do to rotate the secondary. While you are there, put a bit of slight sideways pressure on it. You'll see that the spider vane will flex a little so the mirror moves. Relax and it should come back into position - Just a bunch of metal and plastic connected together! Now, if you back off the three collimating screws a bit (half a turn?) you should find the secondary mirror is hanging off the centre screw and is easily rotated (around the long axis of the OTA). Get a feel for that movement. Nip the collimating screws back up and put your Skywatcher tool in the focusser so that all the Secondary is seen inside the end of the tool (move the focusser in/out - adjust the position of the tool in the focusser). A piece of white paper on the wall behind the secondary should make it more clear where its edge is. Now back to rotating the secondary again (loosen the threw screws) until it appears perfectly round in the view through the tool. Tighten the screws - now proceed with collimation. I'm presuming that the secondary is squarely under the focusser - not towards the spider, nor towards the primary. If so, the central screw has to be adjusted in or out to get this correct.
