Celestron 6x30 LER Adapter for Takahashi Mount

https://orlygoingthirty.blogspot.sg/2018/05/takahashi-em-1s-ersatz-polar-scope.html

This is an adapter that allows a cheap Celestron 6x30 LER finder to be used as a polar scope for an EM-1S mount (may work with other Takahashi mounts as well). This is not a substitute for the superb Takahashi polar scope, but an ersatz replacement if you don't have the polar scope and don't want to pay $300+ for one.

Note that the finder must be inserted in the adapter before the adapter is placed in the Takahashi mount! the adapter is a very tight fit and you will not be able to remove it without a strap wrench.

You must also tap the three circumferential holes with an M4 tap and insert three M4 grub screws which hold the finder scope in place and can (to a limited degree) adjust the pointing of the finder scope.