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Free mirror testing
Don't know who out there has seen this:
http://www.wodenoptics.com/freetest.html Anyone sending in their mirror? My Meade 8" mirror is now about 10 yrs old, and the Aluminum coating is flaking off from the edges badly, Would this adversely effect an optical test? I would not have time to get this recoated and sent to Woden by the Nov cut off time. Any comments? Clearskies! Orion |
#2
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"Orion" wrote in
: Don't know who out there has seen this: http://www.wodenoptics.com/freetest.html Any comments? Let's hope they test better than they type :-) -- Pierre Vandevenne - DataRescue sa/nv - www.datarescue.com The IDA Pro Disassembler & Debugger - world leader in hostile code analysis PhotoRescue - advanced data recovery for digital photographic media latest review: http://www.pcmag.com/article2/0,1759,1590497,00.asp |
#3
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Orion wrote in message ... Don't know who out there has seen this: http://www.wodenoptics.com/freetest.html Anyone sending in their mirror? My Meade 8" mirror is now about 10 yrs old, and the Aluminum coating is flaking off from the edges badly, Would this adversely effect an optical test? I would not have time to get this recoated and sent to Woden by the Nov cut off time. Any comments? Clearskies! Orion what is "Woden Optics" ? Never heard of it . It's not Torus Optics Nova or Zambuto , or else people would know . I wouldn't send any object I actually paid for with time or money to just some unknown website . What if my mirror never makes it back ? What if this Woden Optics is just some startup that will vanish tomorrow and leave my mirror in their storage due to not having paid the rent (I'm not assuming any ill intentions, but things happen with very small companies) ? What testing is done there, what test equipment, what test method is used ? Could be the largest and most expensive Zygo or a home made "wooden' Foucault tester , it's not stated, not shown and not known . And besides, why would a reputable optician who is busy making money bother with this type of free work ? Who would benefit ? I just don't see how the economics of this could work, unless the said optician I'm assuming placed the ad actually would skew the test results to convince people to have their mirrors refigured by woden optics . It just looks too risky , I'm looking forward to learning from other people's experiences before doing such a thing . best regards, matt tudor |
#4
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"Pierre Vandevenne" wrote in message ... "Orion" wrote in : Don't know who out there has seen this: http://www.wodenoptics.com/freetest.html Any comments? Let's hope they test better than they type :-) Caveat emptor... -- Jan Owen To reach me directly, remove the Z, if one appears in my e-mail address... Latitude: 33.662 Longitude: -112.3272 |
#5
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"Orion" wrote in message
... Don't know who out there has seen this: http://www.wodenoptics.com/freetest.html Anyone sending in their mirror? My Meade 8" mirror is now about 10 yrs old, and the Aluminum coating is flaking off from the edges badly, Would this adversely effect an optical test? I would not have time to get this recoated and sent to Woden by the Nov cut off time. Any comments? Clearskies! Orion It is better to test the mirror uncoated anyway, so you could strip it and then send it in. Depending on the results, you could then refigure it before having it coated. Dennis |
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testing is done there, what test equipment, what test method is used ?
Could be the largest and most expensive Zygo or a home made "wooden' Foucault tester , it's not stated, not shown and not known . And besides, why would a The Foucault test is very accurate when done by someone skilled, and the material out of which it is made has nothing to do with it. Also, the possession of a Zygo printout is no guarantee that that instrument was properly used. There may or may not be issues/problems with the mirror test offer, but I don't think that Foucault/Zygo is one of them. Dennis |
#7
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Dennis Woos wrote in message ... testing is done there, what test equipment, what test method is used ? Could be the largest and most expensive Zygo or a home made "wooden' Foucault tester , it's not stated, not shown and not known . And besides, why would a The Foucault test is very accurate when done by someone skilled, and the material out of which it is made has nothing to do with it. Also, the possession of a Zygo printout is no guarantee that that instrument was properly used. There may or may not be issues/problems with the mirror test offer, but I don't think that Foucault/Zygo is one of them. Dennis not sure if it was intentional or you simply didn't get my point. I'll attempt to clarify. I would not send my optics , pay for shipment and then make a decision , be it to keep the optics or refigure , based on some unknown parameters, an unknow test performed by an unknown person with an unknown equipment and unknown skill level. I couldn't care less that Foucault COULD be very accurate . So could interferometry . The problem is the UNKNOWN related to the person who performs the test . Besides, this is for suckers anyway, for people who are afraid of and have no knowledge for testing their own optics .. Any respectable ATM-er would rather learn to test optics himself and would have a few other buddies to double check . I hope I made it clear enough this time . best regards, matt tudor |
#8
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the person who performs the test . Besides, this is for suckers anyway,
for people who are afraid of and have no knowledge for testing their own optics . Any respectable ATM-er would rather learn to test optics himself and would have a few other buddies to double check . I hope I made it clear enough this time . Why do you talk about "wooden" Foucault tester if it isn't germane to your point? In any case, now you say that "Any respectable ATM-er would rather learn to test optics himself". I don't believe that this offer is aimed at folks who make their own mirrors, as they will only test commercial mirrors. In fact, I do think that you raise an issue worth considering, which is the risk inherent in sending someone a mirror. However, I think that many of us have incurred the same/similar risk when sending a mirror for coating. I don't know anything about Woden Optics, but it would certainly be wise to check them out before sending them anything. Given this, it remains an interesting and tempting offer, and I would certainly like to know the results of the tests! Dennis |
#9
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"Dennis Woos" wrote in message
... the person who performs the test . Besides, this is for suckers anyway, for people who are afraid of and have no knowledge for testing their own optics . Any respectable ATM-er would rather learn to test optics himself and would have a few other buddies to double check . I hope I made it clear enough this time . Why do you talk about "wooden" Foucault tester if it isn't germane to your point? In any case, now you say that "Any respectable ATM-er would rather learn to test optics himself". I don't believe that this offer is aimed at folks who make their own mirrors, as they will only test commercial mirrors. In fact, I do think that you raise an issue worth considering, which is the risk inherent in sending someone a mirror. However, I think that many of us have incurred the same/similar risk when sending a mirror for coating. I don't know anything about Woden Optics, but it would certainly be wise to check them out before sending them anything. Given this, it remains an interesting and tempting offer, and I would certainly like to know the results of the tests! Dennis Good! Then, send them YOUR mirror... -- Jan Owen To reach me directly, remove the Z, if one appears in my e-mail address... Latitude: 33.662 Longitude: -112.3272 |
#10
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On Wed, 17 Nov 2004 18:53:14 -0500, "Dennis Woos"
wrote: It is better to test the mirror uncoated anyway, so you could strip it and then send it in. Depending on the results, you could then refigure it before having it coated. Or strip it and star test uncoated it on a bright star. Newtonian paraboloids are straight forward enough with the star test.; I routinely figure my mirrors with an uncoated glass star test. If at one time, the mirror gave great high power images, no real need to test it. Dan Chaffee |
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