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Posts Made By: Paul Kammueller

November 12, 2002 03:42 AM Forum: Equipment Talk

Mystery Scope

Posted By Paul Kammueller
Freakshow. I don't know who made this but I'm guessing f/10 with the converter, that would make sense of the nonsensically large central obstruction as it would imply that the mirror system is designed to f/5-f/7.

A very strange-looking beast.

November 12, 2002 10:01 PM Forum: Telescope Making

Finder scope conversion??

Posted By Paul Kammueller
Got a hacksaw? Chop the tube and grab the .965" diagonal from your old 60mm refractor (everybody has one of these from their childhood hiding in a closet somewhere). Presto!

November 19, 2002 09:00 PM Forum: Deep Sky Observing

Planetary Magnification Increments

Posted By Paul Kammueller
I would say that 225x is not necessary, and really neither is 180x if you have 160x and 200x. In my experience magnification increments of less than 20% results in eyepieces going unused.

November 19, 2002 09:51 PM Forum: Off Topic Discussions

Myth and fact in regard to spy satellites?

Posted By Paul Kammueller
Well, to read the headline would probably require resolution at least as good as 1/4 inch, which at a distance of 60 miles I think equates to resolution on the order of 0.01 arc sec or so, which would require exceptional seeing conditions indeed, not to mention an objective lens or mirror bigger than a house.

November 20, 2002 10:17 PM Forum: Off Topic Discussions

Isn't it interesting how war decorum has changed?

Posted By Paul Kammueller
Technology changes everything. The Civil War saw the first really modern military technology with exploding shells, more accurate rifles, etc. They continued to fight by old methods, massing huge armies across from each other in wide open fields, almost always with disastrous results.

Didn't take long for tactics to change. No more dressing up in your Sunday Best to salute your enemy on the field. More recently, I think covert action is being realized as more efficient, like business trying to do more with less manpower. And with the annihilative sorts of weapons there are now there's little point in making any pretense about being gentlemanly about war anymore. Now the game is played to win, period.

November 21, 2002 04:10 AM Forum: Off Topic Discussions

Astronomers vs Church

Posted By Paul Kammueller
Is this a troll post? Defending the conviction of Galileo? Even the Vatican has recanted it, this is a joke, right?

"Galileo was convicted of teaching heliocentrism, when he had been forbidden to do so. It was a case of insubordination."

In other words he was convicted of teaching the truth. Off with his head.

November 22, 2002 05:16 PM Forum: Telescope Making

Lengthening F.L.

Posted By Paul Kammueller
You must have a typo in here somewhere, it's a mathematical impossibility for a mirror to have a positive focal length less than its radius. Did you mean 60"?

November 26, 2002 10:20 PM Forum: Telescope Making

A real pain. Collimating !!!!

Posted By Paul Kammueller
I've found after getting things on pretty well by eye-balling, is easiest to use a star to de-focus on and see if the blur circle gets 'lopsided' and adjust based on which side is 'lopsided'.

In getting the secondary straight, it doesn't yet matter if the primary is level yet. Forget the centers for a minute and fiddle with the secondary until you can see the outer edge of the primary in the secondary's reflection, about equidistant in from the edge of the secondary surface all the way around.

Then worry about straightening out the primary, get the reflection of the secondary roughly in the middle and then fine-tune with a star if necessary (this seems the most accurate collimating method to me).

Have never used a laser-whatzis or cheshire or what have you. I'd probably be lost with these things, would probably laser myself or something. It seems like once you get the hang of this it gets to be very second-nature.

November 27, 2002 04:02 PM Forum: Equipment Talk

Planetary scope specs

Posted By Paul Kammueller
Go loooong! f/6-f/8 for newt, f/12-f/15 for a refractor. Saves you a lot of headaches with coma in newts, less chromatic aberration in refractors, much more forgiving of collimation errors, and can use smaller secondaries with newts. Also easier to cut out stray light with longer f/ratios which is critical to increased planetary contrast.

Also with planetary viewing you'll be using mainly higher powers and having longer f/ratios will save you from fussing around with barlows and short-eye-relief 'peep-hole' eyepieces.

Equatorial tracking mount is nice, but certainly not required. I track pretty easily at 400-600x with my 10" f/8 planetary dob.

November 29, 2002 04:16 PM Forum: Telescope Making

melting my own glass

Posted By Paul Kammueller
I think you have to get to about 3000 degrees F. That compares to your kitchen oven that probably goes to about 500 degrees.

Also might have an interesting time generating glass of sufficient optical quality without lots of bubbles and stuff. But like the idea -- talk about building from scratch!! Gonna plant trees to generate lumber to make the mount? ;-)

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