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Adjustment of the main mirror

DIY Collimation
Takahashi Epsilons •3 replies•173 views
Markus Gorski avatar
Markus Gorski avatar
Hello, everyone,

Again and again I was amazed that the adjustment of the main mirror of my Epsilon 130D often didn't hold until I realized that it wasn't protected at the back. If you touch it too hard, you might shift it.



I solved the problem by attaching a Bahtinov mask to the back. This protects the main mirror against accidental touching.




Maybe this will help someone...

Kind regards and clear nights, Markus
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Götz Golla avatar
Götz Golla avatar
Hi Markus,
the mirror of my E130 doesnt shift when I touch it at the back. When the mirror shifts by touching it, chances are it also will shift when the orientation of the telescope changes.  Could it be that your mirror is not properly fixed by the holding brackets ? I would investigate this further by removing the mirror case and carefully observe the behaviour of the mirror when you touch the back while the case is sitting on your desk.
Regards,
Götz
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Markus Gorski avatar
Markus Gorski avatar
Götz Golla:
the mirror of my E130 doesnt shift when I touch it at the back. When the mirror shifts by touching it, chances are it also will shift when the orientation of the telescope changes. Could it be that your mirror is not properly fixed by the holding brackets ? I would investigate this further by removing the mirror case and carefully observe the behaviour of the mirror when you touch the back while the case is sitting on your desk.
Regards,


Hello,
Thanks for the feedback!
It's not like the mirror moves at the slightest touch. It happens when I put the telescope on the mount and accidentally grab the back of it too tightly.

In fact, the dealer fitted the mirror with a ring bezel, so it may actually have some play.
However, the mirror has so far held its position perfectly when the telescope is swivelled.
But I'll take your tip when I get a chance and see how the mirror is fixed in the mirror cell.

Best regards Markus
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Götz Golla avatar
Götz Golla avatar
Markus Gorski:
Götz Golla:
the mirror of my E130 doesnt shift when I touch it at the back. When the mirror shifts by touching it, chances are it also will shift when the orientation of the telescope changes. Could it be that your mirror is not properly fixed by the holding brackets ? I would investigate this further by removing the mirror case and carefully observe the behaviour of the mirror when you touch the back while the case is sitting on your desk.
Regards,


Hello,
Thanks for the feedback!
It's not like the mirror moves at the slightest touch. It happens when I put the telescope on the mount and accidentally grab the back of it too tightly.

In fact, the dealer fitted the mirror with a ring bezel, so it may actually have some play.
However, the mirror has so far held its position perfectly when the telescope is swivelled.
But I'll take your tip when I get a chance and see how the mirror is fixed in the mirror cell.

Best regards Markus

OK, I understand. I like the idea of using the Bathinov mask as an additional protection for the mirror.
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