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I heard back from Ray at Newport glass today, the mirror is out of the oven and almost ready to ship, hopefully it will get here in a couple of weeks or less. Then it'll go to Mark asap. There was one small mishap (the mirror moved while being fused in the oven) and the back surface of the mirror will have diameter 400mm while the front is 406mm but no great problem.
Trevor I don't know yet what the final weight will be, I made sure Nemesis had a much stronger mirror cell than Lexx to stop some of the flexing that I think causes most of my decollimation problems with Lexx. But all up, sans optics, the metalwork would only be maybe 10kg. With optics included and all the rest (bolts etc) probably looking at close to 30kg. By comparison Lexx is 23kg fully loaded.
I have 4 Losmandy counterweights, Lexx needs 3 of them but I'll likely end up with all 4 on the bar for Nemesis. It will be more-or-less permanently mounted on the pier, so I also have to build a roll-off cover that will fit over it.
Paul, the shorter focal length is ok, I can screw on more T adapters to move the camera further away from the filter wheel if I need it. The longer term plan is to upgrade to the Grasshopper2 camera which has 5.5u pixels, that gives me back the image size I lose from the shorter mirror plus some more.
I went shopping today and bought some of the nuts and bolts I need, also re-checked everything against the measurements I put into newt, still looks ok.
cheers, Bird
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