By Phil Holt, Mornington, Vic, Aus. in association with the Mornington Peninsula Astronomical Society
All sky camera
These experiments were inspired by Chris Schur in Sky and Telescope Magazine, June 1982, (Vol 63, pp621-624) and August 1982, (Vol 64, p199). He used a convex chrome plated car hubcap and mounted a 35mm SLR camera above it photographing the reflection of the whole sky. He now has material of this nature on his web site.
I have conducted experiments with a saucepan lid and a truck hubcap so far and found that it is necessary to prefocus the camera on the virtual image in daylight (focus on clouds) as it is impossible to see stars in the viewfinder at night. You also need to look at your slides through the wrong side to correct for the fact that you are photographing a reflection. This gives the impression of looking up at the sky, with a camera silhouetted (in the way).
Aurora October 29, 2003
Spectacular aurora visible on south horizon at 1130 UT, October 29, 2003. South is to the bottom, east to the left. The crescent moon illuminated the clouds. Note the rays and the blue colour band above the red. Kodacolor Gold 200 print film, 1/2 minute with 50mm lens at f2.
Faint Aurora May 30, 2003
Aurora just visible on south horizon (marked with an S) 1154 UT, May 30, 2003. Fujichrome 400, 3 minutes with 50mm lens at f2.
Aurora April 18, 2002
Faint aurora just visible on south horizon at 1230 UT, April 18, 2002. South is to the bottom, east to the left, the Milky Way runs East-West across the centre of the image. The image of Alpha Centauri was distorted by a flaw in the surface of the hubcap. Ektachrome 400 pushed 1 stop, 3 minutes with 50mm lens at f2.
Summer sky with Orion
January 02, with the camera mounted on a single supporting strut. South is to the top, Orion is visible near the bottom, Saturn and Jupiter below that.
Spring sky, Milky Way
September 01, South is to the top. Milky Way runs across the centre. Southern Cross and Pointers are top left. Mars is the bright object just below the camera.
This image was taken in July 2001 with a new hubcap. It was more spherical and the reflection of the camera is less obtrusive. The bright object in Scorpius (centre right) is Mars. South is at the top, West to the left.
Aurora 2000
Aurora on April 7 2000 11:11UT. South is to the top, West to the left. When I was taking the photo, I was not aware of the aurora, it was obviously very faint and covered much of the sky. This was taken using an earlier flat-ish truck hubcap.
The hubcap camera
Pictured right, is the hub cap camera on a wooden single strut mount. This results in pictures with less of the sky obscured by legs. Some of my photos were taken with the camera on a tripod placed above the hubcap, and these are the ones with 3 legs in shot.
Jeffrey R Charles has plenty of detailed information about reflecting all sky cameras, including a way of avoiding tripod legs in the image. He gives details on the construction of an axial strut.