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Aug 02

Bended pier

Usually most privately used observatories use a straight pier – made either out of concrete or steel. A problem that might arise is that, in certain positions (usually pointing towards the zenith and/or the meridian), the scope may hit the pier. We also experienced this problem, so we had to forget about imaging around the meridian (10 degrees east and west of it, actually), if we didn’t want the ccd camera to hit the concrete.

There would be a few possible solutions to this: A slimmer pier (but at the cost of stability), or a bended pier. Looking at the homepage of ASA (Astrosysteme Austria), from whom I also got my mount, I found their DDM160, a massive equatorial mount only sold together with a bended pier.

After a few rounds of calculations we went for such a solution. It looked stable enough (even if visually it somehow doesn’t look right). To get ready to mount it, we had to get rid of out old concrete pier, which by now was too high, and then we had to get the remainder level.

Knicksäule

Bended pier with ASA DDM85-XL and a GSO RC 12″ on it

Mounting the bended pier wasn’t so easy: The concrete slab was actually too small to be able to bolt the ground plate of the pier down with enough safety. With four bolts we anchored it down (later on we figured out it wasn’t enough…). The bend pier (with its 120kg) then got mounted on the base plate, and then the DDM85-XL (we let ASA upgrade it) came on it.