Bosque del Apache National Wildlife Refuge  (page 6)

 

Shooting the moon

While at Bosque, one of my objectives was to capture some images of the cranes or geese silhouetted by a full moon. We coincided this trip to a time when we know the full moon would be present. You will need to stake out a location where the birds will be flying in for their evening roost such that the full moon rising will be in the background. The area to the left of the Flight deck worked out well for this positioning. On the first day, the moon was already about 5 degrees above the horizon at sunset. This was good news for having some reasonable amount of light for the birds and a moon that would not be as bright relative to the rest of the composition elements. One of the challenges is controlling your exposure to not blow out the highlight details of the moon. So as it gets darker, this becomes more difficult while still maintaining any detail on the bird or surrounding scenery. The other challenge as it gets darker is maintaining a high enough shutter speed. You will definitely be having to make some trade-offs in trying to balance the speed with the relatively low light, while also avoiding to blow out the details on the moon. I found for this first night when the moon was higher in the sky at sunset the best strategy was to identify a bird or group of birds that you believed would be passing in front of the moon, with the camera shutter control in burst mode, and the exposure metered for the moon pushed to the far end as you can get away with. Then you should track the bird for your auto-focus lock with one eye in the viewfinder, and keeping the other eye outside the camera waiting for it to pass in front of the moon. Then as the bird gets close, just let it rip on the shutter release in the fastest burst mode your camera supports. If you get lucky you may have multiple opportunities with each new wave of birds fly-in for their evening roost. As it gets darker you will have to continue to adjust your exposure settings, and the situation will become more difficult to maintain focus lock on the bird. I ended up capturing the following photo of a Sandhill Crane against the moon as shown above.

On the second night of photographing the bird-moon silhouette effort, the moonrise occurred about 30 minutes after sunset. As a result, by the time the moon was high enough in the sky, most of the cranes had landed for the evening. But the good news was that the later arriving geese where just starting to come in. However, it was too dark to easily acquire and track the geese in the sky with the auto-focus or get any kind of reasonable exposure without the geese being a full silhouette. So I decided on a different strategy instead: I fixed the camera to point at the moon, and setting a manual exposure metered for the moon and a shutter speed of 1/800th of a second and maximum aperture (f/4), setting the ISO to whatever I needed to maintain this. I then manually focused on the moon, then slightly backed off toward the foreground in an attempt to guess on what setting would be needed for any birds passing in front of the moon. Then while staring into the viewfinder I then would fire off a burst of shots whenever I saw a bird pass in front. This technique worked surprisingly well given the challenges of the situation, but did require some quick chimping in the middle of the action in order to tweak the focus. You will also need to make continuous tracking adjustments as the moon rises in the sky to keep it centered in your viewfinder. .