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Paul M

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About Paul M

  • Rank
    Trailer Trash
  • Birthday 29/09/64

Profile Information

  • Gender
    Male
  • Interests
    Astronomy, Scuba Diving and walking my daft Labradoodle.
  • Location
    Fylde Coast (Home), or Rural Cumbria (Away)
  1. paying for astronomy software

    I've spent a lot of money on planetarium software from various vendors over the years, particularly in the 90's. Now I use Stellarium on desktop and Skysafari on my mobile devices. I recently upgraded SkySafari 4 Pro to 5 Pro at full price. Not that I needed the extra features, such as they were, but because I think it's very good value for money and I wanted to support future development. I wouldn't pay hundreds of pounds for some of the high end PC packages unless I needed a particular feature only available at that price.
  2. I saw the pair this morning on my way home from a night shift. I'll be sleeping tomorrow morning so won't see the best of it. Just a shame it didn't happen near Venus' maximum elongation, in a black sky. It's going to need a really low and clear horizon to allow an observer to get a good view in a reasonably dark sky.
  3. Aurora alert

    The sky has cleared here on the Fylde but it doesn't seem very transparent. No sightings for me but my horizon is nowhere near low enough to see the limited displays shown in the images above. Looks more promising for N Scotland and beyond.
  4. Overseas supplier dispute advice?

    I'd have named them in the first post where their behaviour is already beyond acceptable. They have the money and the goods and show no sign of following up with what they have told you so far. If they get some bad publicity from it - tough! We live in a world where the internet can make or break a business. I spend hours looking through reviews and forums before I make a big or high risk purchase. I've owned a couple of businesses over the years and although not open to the internet I relied heavily on reputation and word of mouth. If I felt (didn't wait for complaints!) that I was underperforming I'd give fair warning in advance, give a status update and knock myself out to rectify the situation. I expect others to do the same.
  5. Indeed, an enjoyable watch and a very approachable approach to imaging the night sky!
  6. A couple of years ago I had the very great pleasure of visiting the Hayden Planetarium (NYC) and watching the then current main show. Written and narrated by Neil Degrasse Tyson. The subject was dark matter and dark energy. It offered no answers, just an insight into the size of the holes in our understanding of the large scale Universe. Deeply thought provoking!
  7. I did exactly that with two young ladies last winter. I pointed them towards the Pleiades without any prompting of what they might see. They both counter well over 7 stars each. Now and for some years they've been a fuzzy blob to my unaided eye Yet I seem to pick out more and more each time I look a jupiter through my scopes. So I'm still on the upslope of increasing skill outpacing deteriorating eyesight
  8. Intere Interesting! It's possible to put the "whole" Mandelbrot beetle within a circle of precisely known circumference. So the infinite length border of the beetle must require an infinite spatial regression to make room for the fractal complexity. Then we have a problem with the Plank Length? A simple "yes" or "no" will suffice
  9. New puppy naming challenge

    Our girl Labradoodle was called Jess (or Jessica when she's in the dog house). Then a young lady called Jess (Jessica when she's in the dog house!) moved into our lives and the dog had to be renamed. So now she's known a Doodle or The Doodle or Doodleburger. Calling "Doodleburger!" gets the strangest looks out and about On that basis I think dogs respond to any name so long as your intonation is on their wavelength.
  10. I'll agree that if the scope, mount and handset are all in agreement then the mount is sucessfully star aligned. Everything else is to the users taste and requirements!
  11. Yes, it's the only means of positional feedback from the axes. Some mounts have two per axis so the mount can be slewed with the drives disconnected (clutches released) without losing it's positional fix on the sky. The NEQ6 only has 1 per axis so once the clutches are released the mount has no way of knowing if and where the mount has moved.
  12. The OP said he selected Vega as an alignment star and the mount/scope slewed to a point miles away. Two things here, I think. The home position wasn't calibrated. The encoders had no idea where the mount was pointing while in the home position. So no chance of finding Vega. Also, if the mount thinks it's pointing at Vega make it so! Undo the clutches so as to avoid moving the encoders (remember, it thinks it's already on Vega), get Vega in the eyepiece, lock the clutches and fine tune with the hand control. Using the handset to fine tune an alignment star also fine tunes the encoders positional fix. After accepting the Vega alignment the second alignment star should be within or very close to the field of view. I've never used the home position because I have to set up each time I use the scope. Too much room for movement and loss of calibration. My way of doing it takes no time and cuts out what I consider an unnecessary step for portable set-ups.
  13. Ah Mandelbrot! Back in the early 90's I read a book called "Chaos" by James Gleik. It was my introduction to Chaos Theory and the Mandelbrot beetle. The book showed the simple iterative formula and how Mandelbrot "mapped" the results on a simple graphical display. I had a BBC model B computer then, running good old BBC BASIC. I had a go at writing an algorithm to see if I could generate my own beetle. Against all the odds it worked. It was unbelievably slow by today's standards and took a whole evening to generate the simple 1:1 beetle. I didn't write a user interface so zooming was a matter of changing variables in the algorithm and letting it run. It was a huge success but at high zooms, still only thousands of times, it took days! Colour was the key. The beetle was anything but black and white. In fact, as explained in the video, each pair of coordinates would be run through the algorithm. They either tend towards 0 or infinity very rapidly dictating that they were either within the "set" or outside of the "set". Some coordinate pairs would be slower to diverge either way and the number of iterations required to "test" each pair would decide what colour to plot those coordinates on the screen. So all that crazy detail in the beetle is actually the "coastline" of the beetle, the infinitely complex boundary between those point within the set and those points outside the set. The graphical representation is only part of the beauty. Having played with it numerically is truly mesmerising. There is no way of knowing if any point in the plane is inside or outside of the set without testing it. You can't look at the surrounding pattern and assume anything because on a finer scale it changes to something else. Infinity at your fingertips!
  14. I must agree that the box standard manual is by far the weakest aspect of the Skywatcher products I own!
  15. The equatorial mount is designed so that once an object is in the field of view you only need to track it in one axis, right ascension. This is achieved by having that axis aligned with Earth's axis. That is where polar alignment comes in. Long before GoTo was invented we could have a simple motor drive (even clockwork) or hand operated knob on the RA axis that would keep an object in the field of view with minimum effort. It also meant that setting circles could be used to locate objects but in reality setting circles on mass produced amateur mounts are an almost useless novelty. It is important that the polar axis is aligned accurately so that only the RA axis need moving to track an object. So we make every effort to do so. Then came along computerised GoTo mounts. They don't need to be equatorial. AltAz can be driven with a GoTo computer but it's not ideal for astrophotography due to field rotation. On an equatorial mount the computations are made on the basis that it's polar aligned but that only tells the mount how to expect the sky to move and not where in the sky it's pointing. Somehow the position encoders on both axes need to be "aligned" with a couple of points in the sky to inform the computer where the telescope is pointing. That is exactly what 2 or 3 star aligning achieves. The mount needs to know your geographical position, your time and where the telescope/mount is pointing. Then it's away! If it's fully aligned and then placed in the home position and not disturbed it can be powered down and then GoTo operation resumed without re-alignment next time you use it. It looks at elapsed time since power down and calculates where the axes should now be pointing. But for "home" to have any meaning it needs to be place in "home" from a known position. Polar alignment is the mechanical process of getting the mount aligned with Earth's axis. Star alignment gives the mount's software a positional fix on the sky.
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