Tord
Well-known member
Hi
Is anyone else experiencing slightly loose extension tubes, and misaligned setup?
I found out the other day that there is no way to tighten the screws in such a way that the tube is perfectly aligned with the focuser. For some reason there are two screws only on the focuser, positioned at about 120 degrees angle from each other. On purpose? The slight play that exists between the extension tube and the focuser allows the screws to excercise a radial pressure that will result in a slight angle, yet noticeable at close inspection.
Is this a defect, or could the tube or focuser be manufactured outside tolerances? Or is it "by design"?
What I did to workaround the issue was to wrap the extention tube in one layer of plastic adhesive tape, which pretty much provided a tight fit so now the misalignment is gone, at least it is not measurable with the naked eye.
Maybe I should also have added that the extension tube is manufactured with an "undercut", I suppose it is a measure of safety to prevent the extension tube from accidentally sliding out of the focuser.
/Tord
Is anyone else experiencing slightly loose extension tubes, and misaligned setup?
I found out the other day that there is no way to tighten the screws in such a way that the tube is perfectly aligned with the focuser. For some reason there are two screws only on the focuser, positioned at about 120 degrees angle from each other. On purpose? The slight play that exists between the extension tube and the focuser allows the screws to excercise a radial pressure that will result in a slight angle, yet noticeable at close inspection.
Is this a defect, or could the tube or focuser be manufactured outside tolerances? Or is it "by design"?
What I did to workaround the issue was to wrap the extention tube in one layer of plastic adhesive tape, which pretty much provided a tight fit so now the misalignment is gone, at least it is not measurable with the naked eye.
Maybe I should also have added that the extension tube is manufactured with an "undercut", I suppose it is a measure of safety to prevent the extension tube from accidentally sliding out of the focuser.
/Tord
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