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Comment: Re:Dobsonian (Score 1) 187

by SteveAstro (#47744567) Attached to: Slashdot Asks: Cheap But Reasonable Telescopes for Kids?

The steppers are now all "microstepped", which basically means you don't see quantisation from the drives, but you can't "beat" field rotation, and you'd be surprised how few de-rotators are out there - the imaging guys pretty well all use equatorials, with their attendant problems.

ALL mounts have their issues - an equatorial can't view the area around the celestial pole, and is rarely as stiff as an alt-az for the money. An Alt-az has the field rotation issue, and can't view its zenith.

Mount wars get like computer language wars....

Comment: Legend (Score 3, Interesting) 57

by SteveAstro (#45983757) Attached to: Telescope Designer and Astronomer John Dobson, 1915-2014

Another, probably apocryphal, story was John claimed to have star tested a scope using the glint of light off the eye of a blackbird, perched on a telephone wire down the street - really, really good telescope makers can identify the condition and quality of a mirror by studying the shape of the image from the scope just inside, and just outside focus.

Comment: Re:Nice guy (Score 4, Interesting) 57

by SteveAstro (#45978409) Attached to: Telescope Designer and Astronomer John Dobson, 1915-2014

John stayed with us in the UK back in 2002 - that Wikipedia article picture should have me just out of shot... We took him to see the city of Chester - which John insisted on seeing the city walls "The last city I saw with walls was Beijing in 1920" I think he said. We took him to North Wales to see the sights there, and then he stayed in my home for a couple of memorable nights, when he baby-sat my eldest son while I rushed my baby son to the ER having found him bleeding and screaming after climbing a bookcase and cutting his head open. "John, I really, really need to get this little guy to hospital. Can you tell my wife where we've gone and look after this one ? " "Aw, sure, no problem". I came back to find John reading a book to my son. I have video of John "lassoing" the kids out in the yard with a rope he always carried to demonstrate with !

One of those visits that will stay with me forever- the youngest son is now 13, and still has the scar......

Comment: Re:Bad call (Score 1) 611

by SteveAstro (#45932203) Attached to: Bill Nye To Debate Creationist Museum Founder Ken Ham

Not many atheists go to warlord controlled countries to delivery medical supplies while unarmed and unprotected. Christians do and that resonates with people.

No, what happens is that many "atheists" go to warlord controlled countries etc , etc, they just don't feel any need to mouth off about why they are doing it, and they are only doing it because they believe in a sky-fairy.

The number of arguments is unimportant unless some of them are correct. -- Ralph Hartley