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Messages 11192 - 11221 of 19605   Oldest  |  < Older  |  Newer >  |  Newest
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11192
I have a 12.5" Telekit with a Pegasus full thickness astrosital mirror and am thinking of adding a second mirror to blow on the face of the mirror. Wondering...
Dave A.
adamsdp1
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Dec 2, 2004
9:53 pm
11193
Dave, I have a fan blowing at an angle of about 45 degrees, from one corner of the mirror box above the mirror. It seems to help a lot. I built a bracket out...
C. Starks
cstarsnc
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Dec 2, 2004
10:09 pm
11194
What ever happened to your quest for a 1 meter mirror? Corning Glass could make you one as well as GE. The folks who built the 100 incher are still in...
william rowland
Ludwigvan_Be...
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Dec 3, 2004
4:31 pm
11195
Bill- Finished mirror or raw blank? Gordon...
Gordon Pegue
gtpdeepsky
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Dec 3, 2004
4:53 pm
11196
A recent off the cuff quote on a 45" was in the $100K range... I suspect these companies would be in the same range if not higher.... my thought is to get 8 -...
Gary Myers
garyk9rx
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Dec 3, 2004
5:58 pm
11197
Have you considered to buy a big telescope from a professional observatory? IIRC there may be a dutch telescope in La Palma for sale? Roger Persson ... 50" ......
gubbenimanen
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Dec 3, 2004
9:00 pm
11198
Exactly your goal was accomplished more than 15 years ago in Southern California. A group built a 48 inch RC on a fork mount in a two- story roll-off roof...
Gregg
starryskyn
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Dec 4, 2004
12:37 am
11199
Yes I believe I am aware of this group - they bought a HiSIS22 CCD camera from my company (RXDesign - US Distributor for the LE2IM camera line) about 10 years...
Gary Myers
garyk9rx
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Dec 4, 2004
1:33 am
11200
A. Jaegers Optics now has a website: http://www.ajaegers.com/ mirror blanks, refractor objectives, etc, etc for sale...
dpertini
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Dec 4, 2004
1:41 am
11201
... i think the most realistic plan of attack would be to get the 48" cellular blank from rockenberger: http://tinyurl.com/5vkqu then get united or newport to...
vid1900
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Dec 4, 2004
2:41 am
11202
Looked at it - do not want another pyrex mirror. If I am going to invest into something of this magnitude it HAS to be such that it can be much more readily...
Gary Myers
garyk9rx
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Dec 4, 2004
3:07 am
11203
Making a thicker mirror as a plain disk will mean you will have to refridgerate it in the daytime heat. The glass will perform like a very good insulator....
Gregg
starryskyn
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Dec 4, 2004
5:14 am
11204
This may or may not have been discussed before, I do not know. I have a question for some of you that have much more experience then me. I have a Meade...
Paul Cather
pcather23964
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Dec 4, 2004
5:38 am
11205
The 4" is grossly oversized. Meade designed this scope (more specifically, some early GEM mounted version of it) back when dinosaurs roamed the earth and...
John Mahony
jmmahony
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Dec 4, 2004
10:40 am
11206
sorry - did not mean to imply the "webbing" was the issue... indeed if I were to spec it out it would be say a 48", 5" thick cored mirror. Then because the...
Gary Myers
garyk9rx
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Dec 4, 2004
4:06 pm
11207
Paul, I wouldn't assume a 4" secondary is too large, but if you can determine where the focal plane should be, relative to the end of the focuser when racked...
pensack1
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Dec 4, 2004
8:02 pm
11208
You still have boundary layer ... that would be my concern; with a full thickness even if were made of zerodur, the the stored heat rising from the thick glass...
vid1900
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Dec 4, 2004
11:10 pm
11209
Hi Bill, I threw out a few emails and received two replies, Vaughn Parsons had a (quote)36" F/4.5 - 6" Thickness Pyrex - Lightweighted mirror ~200lbs with/ 7"...
Bill
astronutski
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Dec 4, 2004
11:32 pm
11210
nope... still disagree... the boundary layer problem is much easier to solve as all your doing is reducing its thickness - this is accomplished by blowing...
Gary Myers
garyk9rx
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Dec 4, 2004
11:41 pm
11211
... If the observatory has power, why not cool the observatory - roof, dome, walls, concrete, scope, mirror, etc - all day to meet expected night time temps?...
Bob Bunge
bungerob
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Dec 5, 2004
1:17 am
11212
a roll off roof should take care of this... g. ... observatory I ... with a ... layer ... dome, ... night ... domes - is ... move...
Gary Myers
garyk9rx
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Dec 5, 2004
1:26 am
11213
... Can't really agree with this... the Arizona Mirror lab uses old fashion pyrex for the 8-meter and smaller mirrors it makes. The Keck scopes are also...
Bob Bunge
bungerob
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Dec 5, 2004
1:31 am
11214
Still have heat build up in the concrete floor and the walls. If you cool the entire structure there won't be a boundry layer to deal with (in theory), or at...
Bob Bunge
bungerob
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Dec 5, 2004
1:33 am
11215
... Why else would ALL the pro's ... gary, i think the problem of the boundary layer is even a more difficult problem b/c of the larger surface area of the...
vid1900
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Dec 5, 2004
1:41 am
11216
Your points are well stated. I was not aware that the pro's were still using pyrex. I assumed, obviously incorrectly, they were not. Interesting. I do know I...
Gary Myers
garyk9rx
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Dec 5, 2004
3:47 am
11217
... Vid, the pros are back to pyrex because they now have adaptive optics which corrects not only seeing but also any mirror deformation effects. As long as...
Udo Thiel
mojo_blues66
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Dec 5, 2004
4:13 pm
11218
Hi folks, I have a couple of questions about the Kendrick barlowed laser. I own an 11 inch f / 4.3 truss Newtonian and I've always had one small problem with...
Michael Gilbreath
michaelgilbr...
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Dec 5, 2004
5:24 pm
11219
... If you'd asked me ;-), I'd have said the powermate, despite its magnification, won't spread out the beam much at all, and nowhere as much as a regular...
Nils Olof Carlin
nilsolofcarlin
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Dec 5, 2004
6:26 pm
11220
My understanding from a working with some pros a few years ago, is that cost is a big factor combined ease of active cooling both the structures and the...
Bob Bunge
bungerob
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Dec 5, 2004
7:15 pm
11221
... one cloudy day when you are looking for a project, borrow a dry ice fog mach from your local bar and see how evenly you can adjust your fans to push the...
vid1900
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Dec 6, 2004
12:33 am
Messages 11192 - 11221 of 19605   Oldest  |  < Older  |  Newer >  |  Newest
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