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Messages 7113 - 7142 of 12111   Oldest  |  < Older  |  Newer >  |  Newest
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7113
I would not waste time reading anything published in the anti-science Los Angeles times. They are guilty of trash journalism at its worst. If I want to know...
Richard Schwartz
theoboehm
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Sep 1, 2005
2:53 pm
7114
... science Los ... If I ... have done ... and ... I believe John still does. He's still fighting anyway. My impression of John ( I only met him this summer,...
grayco4
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Sep 1, 2005
4:12 pm
7115
Greetings, I've been thinking about this and have a question that some of you might like to comment on. The light from celestial objects arrives here...
grayco4
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Sep 1, 2005
10:56 pm
7116
A binoviewer gives the illusion of 3D. For true 3-dimensional effect, each eye must view the scene from a slightly different perspective. Remember the old...
Bruce MacDonald
vorpalswordsman
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Sep 2, 2005
12:42 am
7117
I have tried PLOP to calculate the deform of primary mirror. A 15mm thick 16" mirror on a 9 point support, will have 4.23354e-05mm P- V error, which is less...
Wah!
wah_is_me
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Sep 2, 2005
4:32 am
7118
... effect, ... Since the rays of light from celestial objects are essentially parallel, wouldn't you get the same perspective whether you are looking through...
grayco4
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Sep 2, 2005
5:00 am
7119
You are quite correct on all points. The 3-D effect IS an illusion, but it is a very useful one. So whether you're using a binoviewer, binoscopes or even...
Bruce MacDonald
vorpalswordsman
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Sep 2, 2005
2:59 pm
7120
Glen Ray Glen, You could try a good beam splitter to form two images with a full light cone (but setting up such an opticle path array would be a nightmare) or...
talquence
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Sep 2, 2005
3:45 pm
7121
... 05mm P- ... it ... Hi: That's your /surface/ error, the wavefront is 1/6th PV for your example, and of course only if you build it perfectly. Still, it's ...
toolontop
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Sep 3, 2005
7:15 am
7122
I have had the good luck to look through a 6" and 12" binocular in my life, as well as a binoviewer or two. My impression of the binocular is a resounding OH...
Alan Scott
alanne1956
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Sep 3, 2005
7:50 am
7123
In a message dated 9/3/2005 3:15:30 A.M. Eastern Daylight Time, toolontop@... writes: ... 05mm P- ... it ... I think the limitation to a thin mirror...
timavv@...
tiafolla6505
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Sep 3, 2005
1:09 pm
7124
... different ... don't get a bunch ... thickness ... be happy with ... Hi Tim: That's why the original poster should search the archives both for this list...
toolontop
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Sep 5, 2005
2:48 am
7125
Is there any softwares or formulas can show how a mirror is too thin? And how to minimize the astigmatism while slewing the scope around to different...
Wah!
wah_is_me
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Sep 5, 2005
5:54 am
7126
Hello Mark, Below you seem to alude to developing a thin mirror for an active cell technology. Are you refering to astatic type cells or something more...
Preston
preston_enge...
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Sep 5, 2005
2:08 pm
7127
In a message dated 9/4/2005 10:49:53 P.M. Eastern Daylight Time, ... Mark, I wasn't trying to steer him away from thin mirrors per se, only that he needed to...
timavv@...
tiafolla6505
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Sep 5, 2005
3:42 pm
7128
Hello, has anyone made a SCN or SCT? I like to know how to translate the parameters in ZEMAX into something I can use to make the corrector. Thanks Don...
glasspusher2001
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Sep 5, 2005
6:23 pm
7129
There's no formula or such as to when a mirror is too thin. It is just that as the thickness of the mirror is decreased, the skill of the grinder needs to be...
Bob May
a52chevybob
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Sep 5, 2005
7:23 pm
7130
There is an Excel calculator available on the web for doing the corrector by the vacuum pan method. All it needs is the diameter and focal ratio of the...
Bob May
a52chevybob
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Sep 5, 2005
7:25 pm
7131
Hi Preston: I believe it was more of a direct reference ;) but I'll say what I can. It's something I was asked to make for a prototype technology; it's not...
toolontop
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Sep 5, 2005
9:10 pm
7132
Hi Tim: Oh good, that's what I thought but it wasn't too clear. The standard recommendation is still make thicker mirrors first than go thinner but the...
toolontop
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Sep 5, 2005
9:16 pm
7133
Thanks just what I needed, now is there a guide to the thickness needed? For a 11" can I use 6mm thickness glass? That's probably what the big C uses in their...
glasspusher2001
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Sep 5, 2005
11:05 pm
7134
... The number I've seen a lot of is D/40, but I've also seen D/50. With a diameter of 11 inches, though, you can't use a metric corrector thickness; you'll...
rflrs2000
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Sep 5, 2005
11:22 pm
7135
... http://www.bbastrodesigns.com/tm/tm.html A student in my mirror grinding class has completed a 16 inch that is 1/4 inch thick. We are surmising that...
Mel Bartels
Mel_Bartels
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Sep 6, 2005
12:31 am
7136
... GR True Bino-scopes are about achieving noise cancellation giving you 40% higher contrast than a single mirror. This can result in views equivalent to an...
Mark Suchting
starspangled...
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Sep 6, 2005
12:53 am
7137
Amazing Mel, how did he support the mirror during polishing and figuring? How good did it turn out? Don ... is 1/4 ... f/3.5, ... the ... notebook ... piece of...
glasspusher2001
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Sep 6, 2005
3:01 am
7138
Thanks Mark, I've followed these systems in the pro scopes but did not know that the technology could be applied to ATM's budgets. Do you know how the wave...
Preston
preston_enge...
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Sep 6, 2005
2:33 pm
7139
... I agree,, How did he support it during working phases? I have a similar mirror from almost 20 years ago, that i tried making LONG before i ever heard of...
Joe
nssdz
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Sep 6, 2005
8:11 pm
7140
From a post by David Davis: "I took the completed uncoated mirror, mounted in a foam tube, to the Oregon Star Party last weekend. Star testing showed the...
Mel Bartels
Mel_Bartels
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Sep 6, 2005
10:51 pm
7141
Hi Preston: I'm not really free to provide details, but you're going in the right direction for the most part. I can say that if it works as it was described...
toolontop
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Sep 7, 2005
2:12 am
7142
Thanks Mark, I'll just await it's public unveiling. Please do keep us updated. I've just done a cursery search of Shack-Hartmann and Lenslet arrays and am...
Preston
preston_enge...
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Sep 7, 2005
3:02 am
Messages 7113 - 7142 of 12111   Oldest  |  < Older  |  Newer >  |  Newest
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