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New setup for telescope 167/1145 (November 2009)

The 167mm Newton telescope is now attached to a Takahashi EM-200 USD3 mount.

Several parts have just been removed from the old tube:
- the 114/900 telescope in parallel (it was making sense for photographic long exposures before the era of CCDs...)
- the declination motor system.
Its weight has been reduced from 13.8kg to about 8kg.

I did not spend much time or efforts on the adaptation of the optical tube. Still, it is made with four aluminium bars. Aluminium has a high coefficient of thermal expansion (twice higher than for steel) and the thermal drift of the focus is noticeable. It's easy to deal with it, I just have to accept to wait 1 to 2 hours for thermal stabilization and to check the focus point every 30min/1h. The focus drift is always in the same direction, with a similar amplitude which makes it almost predictable.