09-October-2011

Autumn New Jersey Night Sky Time-Lapsed Video.

After nearly two months of rain, rain, and cloudy skies — we finally have been able to see the sun and very blue skies. At night, I have been using the time to get night sky images, as well as lunar images through some of my exotic 300, 400, 500, and 600 mm lenses. One of the problems I was having for the overnight time-lapsed images was that the lens would get covered by condensation during the night and ruin the night sky images. ARRG! As the weekend progressed, the temperature rose and the relative humidity decreased. I finally got a full night image set with limited problems with condensation. The first set in the video was taken with a Nikon D3 and 16 mm f/2.8 fisheye lens looking north from my back deck. The second set was taken with a Nikon D3s and 14-24 mm f/2.8 lens @ 14 mm. There was a little bit of condensation that impacted the end of the video from this lens.

Lessons learned: 1) I need to look into a resistive heater to keep the lenses warm enough to prevent condensation. 2) I didn’t know that the 14-24 mm lens would creep if pointed straight up — during one night the focal length changed from 14 to 18 mm. For the last night, I used Gaffer tape to fix the focal length of the lens at 14 mm. 3) My tripod/heads are not strong enough to prevent movement when I change batteries. Look into an external power supply rather than batteries for long overnight image session.

Author: David Mathre

I am a scientist by training (Eckerd College, BSc; Caltech, Ph.D.). I worked for 27 years as a Chemist in the Pharmaceutical Industry developing processes to manufacture medicines for human and animal health. I now spend my time as a photographer and world traveler. My interests in photography include the natural world, wildlife, landscapes, skyscapes, and seascapes. I have traveled to over 50 countries over the last 10 years, often on Semester at Sea voyages. While at home in New Jersey, I spend time on a home renovation project and expanding my wildflower garden/meadow.

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