Dark Skies

An audio-visual sequence. The photos were all taken with a Canon DSLR. Most used a 5D MkII. The red hydrogen images are more recent and were taken with a 5D MkIII, just by placing a narrow-band (7nm) H-alpha filter in front of the camera lens. They demonstrate that it is not necessary to modify such cameras to photograph at that wavelength.

The camera mountings for the images in the sequence were as follows, illustrating that a telescope really is not essential for getting some interesting shots.

8 shots were simply taken by a camera on a fixed light-weight (Velbon) tripod.
15 had the camera on a basic HEQ5 equatorial mount, driven at a constant rate (no guider).
12 had the camera body at the prime focus of a 254mm aperture f/4.8 Newtonian telescope on the same unguided HEQ5 mount.

In all cases except the opening and closing wide shots of Orion, multiple exposures were stacked, each short enough to avoid stars trailing on whichever mount was used. That required high ISO settings because of the faintness of the subjects. Stacking was done in my own GRIP program. Further details can be found elsewhere in these pages.

The "music" was created (composed would be too grand a term) in 1991 by using a sequencer program and a Yamaha keyboard. It seemed appropriate and it gives me full ownership of the copyright, so I can show the sequence here. You can always keep the sound turned off of course.