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JamesF

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Everything posted by JamesF

  1. Yup, set things up to record the series earlier today myself. James
  2. On mine I have a motorised Moonlite, because that was what was fitted when I bought it. Sadly rather like Göran, mine has been sitting on a shelf for some time, waiting for other work in the observatory to be completed. James
  3. Not Doris "The Gripper" Brown, known throughout Warwickshire for her generous disposition and the warmth of her chinese burns?! James
  4. The Met Office freely admit that they're naming storms so they get publicity with the intention that people will pay more attention and take whatever measures might be appropriate. Then for some reason they go and give them names like "Storm Doris". Who's going to be worried about Storm Doris? You might as well call it Storm Chuckles. Now, Storm Attila or Storm Genghis would have me panic-buying enough tinned food for a month! James
  5. That looks like something from a cartoon, where Roadrunner scoots straight across it when being chased by Wile E Coyote, who falls down the hole in the middle. James
  6. And then there's this piece of, errrm, well, I'm not sure how to describe it really. https://astronomytechnologytoday.com/2018/06/28/miniwasp-parallel-imaging-array/ James
  7. Someone pass the brain bleach! James
  8. I've just read "Carrying the Fire" by Michael Collins (the one who got to stay behind when Armstrong and Aldrin went down to the Moon's surface). He talks about this, because obviously they had to practice docking as part of the preparation for the trip. For Gemini 10 they had to dock with an Agena booster that had already been put into orbit and use that to boost themselves up to higher orbit and "catch up with" a second Agena booster from Gemini 8(?) where he performed an EVA. His description suggests that it is certainly not a simple process to meet up with another object in orbit and you certainly can't just "point and shoot". James
  9. Yes, I agree that not everyone will be able to manage that. He does offer an alternative solution though James
  10. Here's the video. He's showing off, and using a C14. Perhaps he thought a C9.25 would be too easy. James
  11. There's a video on youtube of a method for working around this problem for large SCTs, though perhaps it still wouldn't suit everyone. I believe it involves putting the OTA "corrector down" on a chair or stool and then moving the mount axes to meet it. I'll see if I can find it. James
  12. The roof is about 2.5m wide and getting on for 4m long. I needed two rails (or nearer one and three quarters) end-to-end for each side. This photo taking during construction probably gives you a better idea: My entire build thread is here, if it's helpful. There are a fair few photos. James
  13. I have to admit that I'd not thought of my V rails as noisy, but I have nothing to compare them with and I'm in the middle of nowhere anyhow. It doesn't squeal or anything like that, at least. Quite possibly the roof moving is quieter than a NEQ6 slewing at full speed :) I appreciate the need to keep noise to a minimum when you have near neighbours though. James
  14. Definitely. Nothing has made a bigger improvement to my enjoyment of visual astronomy than working from a comfortable seat. I can't now imagine doing anything else. James
  15. I used FH Brundle for my roof rails, as already linked. My roof is quite heavy -- I welded a steel frame and then fixed OSB to the frame before cladding the sides and covering the roof with EPDM (and it's about 2.5m wide by 4m long). With a smaller, lighter roof I'd certainly be concerned about the wind lifting it off. A shallow pitch roof acts like a wing in the wind and generates lift which can be sufficient to allow the entire weight of the roof to be overcome, at which point it flies off. This has happened to SGL members in the past, even with a fairly substantial roof. Using a C-section runner with the wheels inside, such as is often used for sliding doors, would keep the roof fixed down (one would hope), but may be a little more awkward to make, especially given the additional complexity of horizontal wheels as suggested by Peter (which I agree would be a good idea). One of my greenhouses actually has a slightly more complex "C" section runner which has a "gulley" down the middle that the wheels sit in, effectively preventing them from wandering from side to side. Something similar might remove the need for horizontal wheels. Some of the benefits of using an open inverted V or semi-circular track such as quite a few of us have used are that there's no side-to-side movement to worry about, and the track is easy to fit and keep clear of debris (and potentially ice, which can build up if rain gets into exposed sections, or even form just as a result of condensation on cold metal subsequently freezing). The negative side is that there's nothing to stop the roof lifting off other than its own weight. Some people use turnbuckles or latches to hold the roof down when it isn't in use, and unlock them manually before opening up. I used something similar to these: https://www.amazon.co.uk/Toggle-Action-Release-Holding-Capacity/dp/B075GZRK4K (the actual ones I bought don't appear to be listed any more). Another option is to have some horizontal pins that slide into holes as the roof closes, thus preventing it lifting. This allows remote opening of the roof, but ultimately you may still need something like the above catch to lock the roof firmly in place when bad weather is expected because you don't want it blowing open during a torrential rainstorm. I don't know what other people have used, but I was toying with using some pins like the ones I have on my tractor implements to fit on a 3-point linkage when I get as far as automating my roof. Quite possibly that's overkill One thing to consider regarding freezing conditions: imagine water got into some part of the roller system on a winter day thanks to some blown-in sleet, and as darkness fell and the temperature dropped, producing a night of outstanding best-in-several-years clarity, you then found the roof wouldn't open because that water had frozen. How easy would it be to clear the ice from your chosen design? Ultimately I think I prefer the open rail approach because it's simpler to install and to use, but I see no reason the C-section runner couldn't be made to work if that's the way you prefer to go. James
  16. Nice one. Now you need a remote controlled finger to work the buttons on the remote James
  17. Somehow I have contrived to miss this one, but the images online appear to show a very pretty cluster so I shall certainly attempt to find it next time the opportunity presents itself. Thanks to John for drawing it to my attention. James
  18. Actually, on the topic of levelling, it has just occurred to me for the first time... If my pier tops are absolutely level, and, say, Olly's pier tops are absolutely level (I bet if they are it's only by accident because I'm pretty sure he's not that fussed, but anyhow...), our pier tops will not be aligned with each other because I'm at 51°N and he's at 44°N (and in fact he's eight or nine degrees east of me, too). However, once polar aligned, the RA axes of a mount at my home and a mount at his will be in alignment regardless of the difference in alignment of the tops of the piers. James
  19. It really doesn't matter. By polar aligning you'll take all of that out of the equation. Having the pier adapter level may make it simpler to polar align, but once you're aligned, you're aligned, and whatever state anything below the RA axis is in really isn't important. I actually considered deliberately making the tops of my piers at an angle of twenty-ish degrees to the horizontal so that the alt adjustment on the mounts could be nearer the middle of its range and less prone to bendy-bolt syndrome. James
  20. I'll take either. I really don't have a sweet tooth and I'm not particularly into chocolate, but for some reason I do enjoy a Bounty. Certainly the plain chocolate variety is better, I'll grant you that. James
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