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Tom and Jennifer Polakis | profile | all galleries >> 2005 >> Steward Mirror Lab -- February 26, 2005 tree view | thumbnails | slideshow

Steward Mirror Lab -- February 26, 2005

Jenn on 8.4-meter LBT mirror, Tucson, AZ, 2005
Jenn on 8.4-meter LBT mirror, Tucson, AZ, 2005		 Jenn lies on 8.4-meter LBT mirror
Jenn lies on 8.4-meter LBT mirror		 Her thermal impression locally changes the mirror's figure
Her thermal impression locally changes the mirror's figure

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Herb Johnson 02-Mar-2005 19:31
The interferogram is very interesting for another reason: the zoning or rings on the mirror. If I read the associated chart correctly, those zones are +/- 20nm (nanometers). If you use green light (510nm) as a reference, that would be +/- 1/25th wave or 1/12th overall. I don't know if the chart adjusts for either spherical or parabolic curve; but surely this mirror does not have a long focal length and so any parabolic correction would be large.

In any event, my slightly smaller mirror with slightly larger zones is described in process via this link:http://retrotechnology.com/herbs_stuff/mymirror.html
..and I'll add a link to this gallery page with your permission.

Herb Johnson
John Brinegar 28-Feb-2005 22:41
Great shots of two good subjects. Destined to be classic in the ATM world.
Tom Osypowski 28-Feb-2005 05:23
What a hoot! Including the interferogram was a neat touch. I still can't believe Jenn was actually standing on the mirror.

TomO
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