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View Full Version : Giant Astrocam Astrograph ? Aerial Lens 3,5/606 mm huge



Dr Klaus Schmitt
11-Feb-2010, 15:41
what IQ to expext from such a monster as listed on german 'bay here 270530197820 ?

Peter K
11-Feb-2010, 16:26
what IQ to expext from such a monster as listed on german 'bay here 270530197820 ?
A little bit too expensive for such a big door-stopper.:D

Peter

Dan Fromm
11-Feb-2010, 16:32
Klaus, the USAF data sheets show two 24"/3.5 Perkin Elmer lenses that cover 9x18.

The sheet on the first monster says it weighs 125 pounds, doesn't report AWAR, astigmatism and curvature of field, distortion, longitudinal chromatic aberration or relative illumination, but it does report "average radial and tangential resolution" at full aperture a 0, 10, 20, and 22 degrees off-axis with unspecified film, target contrast, and filter. 25, 20, 15, and 10 lp/mm respectively. At least fit for contact printing. Not clear whether it is fixed aperture.

The second monster looks somewhat like the one on offer, is fixed aperture, no weight given. Radial resolution on IR film at 0, 5, 10, 15, 20, and 22.5 degrees off axis is 27, 27, 25, 21, 16, and 10 lp/mm respectively. Tangential resolution within +1, -2 lp/mm. Nice flat field. Again, full (only) aperture. And the same lack of other data.

Cheers,

Dan

Dr Klaus Schmitt
12-Feb-2010, 07:40
Thanks Dan, I would have expected a bit more resolution!

Well Peter, that door will certainly stay open!!

Dan Fromm
12-Feb-2010, 07:48
Klaus, many, not all, of the lenses made for aerial cameras are snares for the unwary.

AstroZeiss' asking prices encourage wariness.