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About Macavity

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    Main Sequence
  1. Sol - 2017-10-22 - A Few Views

    I think that a fair comment / conclusion, Gav!
  2. Sol - 2017-10-22 - A Few Views

    The main problem with Barlowing my Lunt (50!) was lack of "travel" re. the helical focuser? I could not get enough *in-focus* for most conventional Barlows to work? To Barlow by a factor of (just over?) 2x I eventually found the following setup to work... See Pictures. https://stargazerslounge.com/topic/294836-lunt-50tha-first-light/?tab=comments#comment-3227826 My trick was to use the nosepiece only of higher (3x) magnification Barlow which will give about 2x with a smaller in-focus requirement. ISTR it Works for Skywatcher Barlows. NO idea re. Powermates? DO the nosepieces unscrew? Would I even dare to with a Teleview? BUT it's hard to predict with any degree of certainty exactly where focus will occur with most Barlows?!? I did suggest testing it with a standard refractor of ABOUT the same configuration / focal length. My ED66 has a scale to help. Test with versus without a Barlow?!? Use a distant object during the day. NOT on the SUN of course!
  3. Tube rings..how tight ?

    A lot of Tube Rings function (quite happily) with Felt or Velour linings! I had to remove the existing "fluff" from one set to get them to fit a "different maufacturer" OTA. No point in tightening them too much... A bit of care seemed appropriate re. latter metal on metal scratching potential! With all tube rings: "Jiggle them a bit" while tightening?!
  4. I think one has to be "a bit careful" re. size of things? There are things like a "Classical radius of an Electron". But it is just that... "Classical"? There is also smearing of the quantum mechanical wave functions in atoms. The polarisability of the vacuum where an electron is surrounded by a cloud of virtual e+/e- pairs etc. etc. There is a characteristic length (cross section etc.) for the "electromagnetic interaction" at High Energies. But electrons (and photons) are held to be "structureless" down to the smallest measurable dimensions AFAIK? But the above might contain any number of incorrect statements... Plus I forget so much stuff these days!
  5. Chameleon First Light

    A little confused, I thought the Chamelion was 1296 x 964? (But I might join up too) So (!) [if I'm not wrong] this is a 3.75 micron 1/3" CCD chip that gives ~1280x960 and (seemingly) without any Newton's Rings. To a good approximation ALL I need. A 17% reduction of Pixel sizes and a replacement for my "slightly non-uniform" DMK41. Recently been doing ZWO "tilting" experiments, but I remained rather unconvinced.
  6. Nothing as exciting as that! I did make one of my "whimsical" comments at the time of the great "Diamond rubbing controversy" (qv) - "Coxy" suggested I "Buy his Book!". ISTR I got "Tweet Forwarded" by one of his "standup" mates. For a while terrifying! I only got THREE responses. One NASTY... Another: "Too right mate!" and the third: "Didn't agree", but would "Defend my right to opinion...". Whatever our differences, it is still GREAT to be a citizen of these generally Polite, Scientific and Apatheist Isles?
  7. This has been a thought provoking thread... We have got(ten) away with it so far? lol. I don't have a problem with anything Hawking said. I find the question as to whether scientists should express a personal, political or religious (God) view a *difficult* one. Yes, Brian C, anyone who tells you not to be "political" gets an instant (Twitter) Ban! Sometimes I wonder what it would be like to be famous? A "celebrity scientist" notably! The slavish adulation... The elevated salary... I might be tempted... I'm only human! But such seems to carry an increased credibility / responsibility re. the "Science Fans"? I think I would post exclusively about SCIENCE under my own name. Anything else, I might chose anonimity? No *young person* should follow "old" folks uncritically?
  8. Another question I've often wondered about! That of passive fandom. Reflecting wry comments re. popular Cookery Programs on UK TV. But there could (well) be a LEGION of frenetic "Bun Bakers" out there!
  9. It is possible to see the merits of BOTH sides / protagonists of an argument: https://youtu.be/_2Aw9UGYNsA (Tyson versus Dawkins) Warning: Contains Swearing! But Tyson gives voice to a lot of my circumspection re. "Popularising Science". And, for his part, Dawkins notes that it could be far Worse? (And often is!) Heheh. I avoided all "Philosophical Discussion"... Too "thick"? But I preferred to go "Mess with the Hardware".... The random fun arguing with Engineers... enduring playful taunts of the Technicians... Minorly *worry* as some French Crane driver skimmed my head with 75T concrete blocks after a "good lunch"!
  10. Benzene & Cyanide clouds now... Not looking to great for my Hols? https://phys.org/news/2017-10-noxious-ice-cloud-aturn-moon.html
  11. Drifting off topic again(?), but... I was prompted to wonder about the (latest studies of) "Anisotrophy of the Fine Structure constant". All set to irretrievably damage science a few years back? Or at least cause a slight rethink [teasing] of some theories! I can understand those who might get fed up with science proselytisers publicists and their crusades. There is now a separate discipline they call "Popular Science"? And KUDOS to the grass roots scientists and conventional educators at all levels. But I do feel sorry (exasperated and more) about the stuff (abuse) the National Labs ... NASA, CERN etc. have to suffer "for their science" on a daily (social media) basis. Maybe we should adopt J.K.Rowling of "Science Publicist in Chief": "Go Jo!" And almost FIVE time the "followers" as other claimants!
  12. Antares 2" 1.6x Barlow

    A need for basic funds mostly? But <bumping> the thread anyway... I think it reasonable to await a better review. lol. But I do recall it came recommended on the wider internet. I found little to fault it anyway?
  13. Antares 2" 1.6x Barlow

    Pretty good when I last had one... Japanese Optics? I used it with my Baader Hyperions? One of my first ever SGL sales (to DAZ maybe)? I often wonder what became of stuff...
  14. *Science* will always "assimilate" any dissenters. For folks interested in Physical Constants I used to get a Free (CERN) Book! Perhaps reading for the "terminal nerd" but I could sit for (a few) hours? Remembering now... It's held on the LBL (Lawrence Berkely Lab website): http://pdg.lbl.gov/ (They are openly available to the Public, I suspect...) http://pdg.lbl.gov/2017/html/computer_read.html Random, but... stuff? In past editions there was a PLOT of evolution of measured Speed of Light with time... From (Galileo!) Roemer onwards. At the start the points (error bars) vary hugely! Slowly the values close to the currently accepted value, the error bars get smaller & smaller... then suddenly "boom" it all shifts! After that (certain) constants can become *defined* quantities... But such things are an interesting study in the evolution of experimental technique. Maybe there is a (Scientist) "Psychological" factor at work sometimes...
  15. "Good thinking, Bataman" wo/men? I'm becoming reasonably confident with my stackings, so I delete .AVI files now. I retain (16-bit) .TIF's for the moment. I think I can reasonably exist on these generic Terabyte USB3 disks for now. I do retain some .AVI's that seem to demonstrate something "important" --- Or perhaps reflect exceptional seeing? Thanks for thoughts! All quite reassuring.