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Today I bought a Telrad and delivered to David. Tomorrow, it's the turn of my Moonlite CR2.

David told me that he will order the mirror from John Nichol this week. :)

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    • By Piero
      Could someone post a photo of the altitude bearing, please?
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      I wouldn't want to miss observing the Sun in a full-size 300mm filter, the detail compared to smaller instruments is such a joy to see. I do have an off-axis mask for my 300mm dob but not all the time. If daytime seeing is too bad for such a large scope, I'll switch to a smaller one, but the extra resolution and ease of spotting micro-detail thanks to the brightness is something I can't do without.

      A sheet of 500mm wide Baader fillm allowed me to craft this. I had enough left to cut several smaller filters.

      To protect it I made a storage box from cardboard of obvious origin. The box had to be custom-made to save space in my dwelling, and it also hosts a bahtinov mask for nighttime. At f/5 fine focus is not too hard with the smooth single-speed focuser, but in order to enjoy moments of clarity immediately at high power, I pre-focus with the bahtinov, which sees through turbulence, what a nice invention, and simply wait for calmer air. No need to rush to fine focus and waste precious moments. This mask needs to be copied in some sort of plastic, the cardboard trial proved the number and width of the slits are fine.

      The rear of the filter shows the four clips mating the four button screw heads outside the tube.

      And this lateral view shows the sandwiching. A rigid backing plus two layers of lightweight neoprene foam cut from a cheap mat in tiger-stripe deco, its poor taste matching its 7€ price. The bottom sheet used to be a shower booth panel, my neighbor had in its garage. Hey, do you need that? No? Okay, thanks!

      The Baader film is held between the neoprene sheets by staples and many strips of tape. The neoprene is held to the shower booth sheet by little collars, and its edges are sewn together for a finished look. Oversize 10mm stitches didn't take too long to do, and the foam layers can be separated for replacing the film, something glue would prevent. Holes in the neoprene allow to check that the clips' bolts are always tight.

      Close-up of a clip. They are made of a material whose name I forgot, I only remember it is made in the UK (thanks, guys!). This is a PVC foam that's much easier to cut, drill and sand than full-density PVC, and it's much lighter (thanks, air bubbles!), which is essential for an item that's at the front of a scope where leverage is maximal.

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      Hi Guys,
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      Dear all,
      Recently I purchased one of these dobsons from ES following the good critics I read in several forums.
      The Gen II includes some improved features with respect to Gen I, 2 Nylon pad brakes, Virgin Nylon alt and azimuth support bearings (instead of plastic), counterweight bar included with a couple of 1kg counterweights, a classical ES dovetail for the finder.
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    • By 25585
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