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RC focuser decouplers in Australia
Hi,
I've been following this thread over on cloudy nights where a guy (Nate) has gone to the trouble of creating an extra back-plate that effectively decouples the focuser from the mirror, which is different from the tilt-plate that many use.
The difference being that even if you collimate the primary with a tilt-plate, the focuser will move too, and the field changes. With the decoupler plate, the field stays the same and you only see the effect of the collimation changes without the field moving. Effectively the DSI collimation method then works flawlessly, without having to recentre the telescope. At least that is my understanding.
Has anyone in Australia done anything like this? What are your thoughts? Good? Bad? It involves drilling precision holes in the backplate (yikes! But he is an engineer and knows what he's doing.) and the milled aluminium would add weight and an extra expansion coefficient.
Markus
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