Bulletin of the Eastbay Astronomical
Society
Founded in 1924 at Chabot Observatory, Oakland, California
Volume 77, Number 5, January 2001
The Schmidt Camera and
Amateur Astrophotography
Dr. Kenneth Lum
President, Peninsula
Astronomical Society
Saturday, 6 January, 2001
General Meeting 7:31 p.m.
Lecture 8:20 p.m.
Astronomy Classroom, 2nd Level, Spees Building
Chabot Space & Science Center, 10000 Skyline Boulevard, Oakland,
California
Image
of Comet Hale-Bopp taken with a Celestron 8" f/1.5 Schmidt camera on April
7, 1997 from Lake Sonoma State Park in Sonoma County, California.
The Schmidt camera is a clever coupling of a spherical mirror
and correction lens that permits wide-field images with exceptional
acuity. The 48-inch Schmidt at Palomar Observatory generated the
invaluable Palomar Sky Survey and is perhaps the premier instrument
of this class.
This will be a summary
of the life of Bernhard V. Schmidt, inventor of the Schmidt camera,
from his birth in Estonia in 1879 to his death in 1935 in Hamburg,
Germany. Being interested in mechanical experimentation from an
early age, he sustained a traumatic amputation of his right hand
at age 15 when a pipe bomb he was experimenting with accidentally
detonated. He was subsequently educated in Goeteborg, Sweden and
Mittweida, Germany. He set up an optical shop in Mittweida where
he worked alone making excellent telescope mirrors for sale and
taking on contract work with professional observatories. Schmidt
finally obtained permanent employment at the Hamburg Observatory
in 1926 where he went with Walter Baade, the great German, and
later, American astronomer on a four-month eclipse expedition
to the Philippines in 1929. During this trip Baade expressed the
need for an aberration-free wide-field astronomical camera for
survey work. Upon return to Hamburg, Schmidt invented and built
the first Schmidt Camera in 1930 and showed it to be a camera
capable of extraordinarily sharp, aberration-free images. He subsequently
built one other camera before his death from complications of
alchoholism in 1935.
The ‘secret’ of the Schmidt camera was revealed after
his death by his Director in Hamburg, Richard Schorr, in Germany,
and by Walter Baade in the U.S. in 1931 after his immigration.
Within a short period after WW II, all of the old wide-field astrocameras
based on portrait lenses were replaced by this remarkable innovation.
Dr. Lum will show and demonstrate the operations of a Celestron
Schmidt Camera at the meeting.
Dr. Kenneth Lum is an Emergency Department physician at Kaiser
Medical Center in Hayward. He has been interested in astronomy
since high school in Chicago where he made three telescope mirrors
in the basement optical shop of the Adler Planetarium. He received
his B.S. from the University of Illinois, Ph.D. from the University
of California, Berkeley, and M.D. from Stanford University.
You can learn more about Schmidt cameras by visiting the Astronomy
in California: 1850–1950 exhibit at Chabot Space &
Science Center, and at www.chabotspace.org/vsc/exhibits/califastronomy/schmidtcamera.asp.
DINNER WITH THE SPEAKER
5:27 pm, Saturday, 6 January 2001
PEARL OF SIAM RESTAURANT
5498 College Avenue, Oakland (510) 420-8600
Please call Betty Neall at 510/533-2394 by Friday, 5 January to
confirm your place. Note the time has been advanced to allow everyone
to be able to get to the meeting promptly at 7:31 pm.
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