David's Images of the Day Photoblog
Multi-Exposure Waxing Gibbous Moon — Going Up, Going Down. A ten exposure image of the waxing gibbous moon going up or down using the in camera multi-exposure function. The exposure times were varied in 1/3 EV increments (1/1000, 1/800, 1/640, 1/500, 1/400, 1/320, 1/250, 1/200, 1/160, 1/125, second). The exposures were taken every 30 seconds and used mirror up to minimize camera/lens vibration.
Waxing gibbous moon with 100% illumination (data from the US Naval Observatory site). The full moon is on the 15th. This month the full moon is known as the “Thunder Moon”. Image taken just after midnight with a Nikon D3s camera and Questar 3.5″ telescope (ISO 1600, ~1500 mm, f/16, 1/1000 sec). Raw image processed with Capture One Pro and Photoshop CS5.
A DSLR video and still image of the July “Thunder Full Moon. These were taken with a Nikon D3s camera and Questar 7” telescope. The moon disk just fits within the D3s sensor, and is clipped in the video. The official full moon is on the 15th, but these images and the video were taken within 4 hours of the full moon on the 14th. I used Adobe CS5 Premiere Pro to edit the video. The digital art version of the full moon was created using Nik Color Efex Pro — Weird Lines Filter.
Jet Transiting the Waxing Gibbous Moon. I am still having issues with the video mode automatic gain “feature” with the Nikon D3s. In doors with normal light levels it doesn’t seem to be that much of a problem. However, when trying to take video images of the moon through a telephoto lens, the moon is over-exposed. During the testing, I managed to catch a jet transiting in front of the moon. I happened very quickly (less than one second). The video below shows the transit across the lower part of the moon 1) as is; 2) zoomed in from 100% to 250%; and 3) zoomed in at 250% and slowed down to 33% speed. There was also some cloud cover moving during the sequence.
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I also took some still images of the moon with the same camera and lens, but with a TC-E III 20 teleconverter. The goal was to see how sharp an image of the moon I could get with a 1200 mm lens. Focusing was through “Live View”, and to minimize camera shake used the “mirror up” mode to allow the system to stabilize. The D3s allows the use of “Live View” and “mirror up” because “Live View” is now selected via a button on the back of the camera. You don’t have the ability to use “Live View” and “mirror up”. The first still image of the waxing gibbous moon at 92% illumination was taken at ISO 200, f/8, and 1/200 second. The second at ISO 200, f/16, and 1/50 second. If I did my calculations right for a 1200 mm lens on a FX sized sensor, the moon should only move ~0.2 pixels for a 1/50 second exposure.
A composite of 897 images looking south taken after midnight. I used the Startrails program for creating the composite.
Second day attempts for a DSLR video of the moon continued to be problematic. It appears that the camera is controlling the exposure and not allowing manual selection of aperture, shutter speed, or ISO. The only way I could get an exposure that was not way over exposed was to add a TC-E III 20 teleconverter (effective 1000 mm).
To confirm that there was not a problem with the camera or lens I took this following single image of the waxing gibbous moon with the same setup (Nikon D3s and 500 mm f/4 VR lens + TC-E III 20 teleconverter (ISO 800, 1000 mm, f/8, 1/200 sec))
