Celestron 127EQ Collimation Aide

This is a 3D model of the collimation cap suggested by niuno15 at astronomyforum.net.


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This is a 3d model of a cap used to aid in collimation of the Celestron 127EQ newtonian reflector telecope. This was described by niuno15 in this thread:


This is placed inside the main telescope tube, onto the bottom of the focuser, and provides a target for the reflected laser beam to hit.

This method is also known as the barlowed method, because it makes use of a barlow lens. The Celestron 127EQ has a "barlow" kind of built in to compensate for a shortened tube. This makes conventional collimation difficult, but lends well to this barlow method.

This process is described here as well for normal newtonian reflectors:


Anyway, I modeled this in Openscad, and the scad file is included, so feel free to change some parameters around.



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3775813bd83221d319daa1c54156a274?default=blank&size=40seanocaster added this to the telescope collection ago
4da27e5ea037d649cfda91aa1840c5fb?default=blank&size=40ApacheXMD published this design ago