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Sorry, perhaps I did not explain well. When I adjust the angular position of the elements, the internal reflections from a laser located in the focuser bounce around and some come back to the focuser, when viewed from the front of the scope.
I have a couple of times now concentrated on getting those internal reflections to all meet up at a single spot in near the centre of the focuser, and then adjust whatever was necessary to move that single reflected spot back to the centre of the focuser (right down the throat of the laser producing the beam, as for a Newtonian scope)
When I have attempted this, I cannot seem to get all the reflections back to a single point. I can merge what initially starts out as two dots, one way brighter than the other,but as I make adjustments to shift those two merged points back to the centre of the focuser, another faint dot becomes visible. And it is not at the centre.
If I check the airy pattern when the laser dots (but not the new faint one)are at the centre, the Discs are rubbish and way off.
If I readjust and get the airy patterns to look hallways reasonable, and check with the laser again, the reflected dot, and its faint companion is way off the centre.
I’m guessing that when it is right, all will come together, airy Discs and the central reflection.
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