Photogrammetric surface measurement of the KOSMA 3m-Telescope

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

1

Scientific paper

We have used digital photogrammetry to accurately measure the surface of the KOSMA 3m-telescope's primary mirror. The method uses a large number of optical photographs of the telescope, taken from many different viewing angles to reconstruct the three-dimensional mirror surface. Thin retro-reflective targets are applied to the mirror in the places of interest. With a large format, high resolution metric CCD-camera a series of pictures is taken under many different viewing angles. A computer program compares the image data and constructs a three dimensional model of the target positions. We used approximately 100-230 targets distributed over the primary mirror and about 50 exposures to reconstruct the KOSMA telescope surface. The measurement accuracy is approximately 10 μm (RMS). The measured mean deviation between the initial surface setup and the ideal parabola was confirmed independently by planetary observations at 345, 492, 660, and 810 GHz. The frequency dependence of the beam efficiencies, derived from scans on Jupiter, follows the Ruze-formula for an initial surface error of 35+/-5 microns. This error was reduced by subsequent adjustments using surface maps of the deviations derived from the photogrammetric data sets. New observations of Jupiter to confirm this improvement are pending.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Photogrammetric surface measurement of the KOSMA 3m-Telescope does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Photogrammetric surface measurement of the KOSMA 3m-Telescope, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Photogrammetric surface measurement of the KOSMA 3m-Telescope will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-918804

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.