Archive: Oct 2015

  1. Star Trails over Lake Michigamme

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    Star Trail over Lake Michigamme

    I’ve wanted to experiment with star trail photography for some time, but the necessary conditions are not as common in Michigan as in dryer climates. For success you need a cloudless night with no moon in a location with a very dark sky. The stars finally aligned for me recently when I was camping on the shores of Lake Michigamme at VanRiper State Park.

    Lake Michigamme is midway between Marquette and Houghton/Hancock in Michigan’s Upper Peninsula. The land north of Lake Michigamme is the most remote and unsettled in all of Michigan. I knew the night sky would be as dark as any I’d ever see.

    To capture this image, I set my camera and wide angle lens on a tripod and framed the photograph so that the North Star was centered in the sky. Because the North Star is a pole star, it remains motionless in the night sky while all the other stars appear to revolve around it over time.

    To get a proper exposure, I set the aperture to f/2.8, the ISO to 1600, and took a sequence of 30-second exposures over the course of about three hours. Rather than manually tripping the shutter every 30 seconds, I set my camera’s drive mode on continuous shooting and used a remote cord that can be locked in the on position. It was a cold night, so I climbed in my┬ávan and took a nap under a sleeping bag.

    I ended up with 355 individual exposures. In my studio, I opened the raw files in Adobe Camera Raw and made a few adjustments to the images. Only one plane flew overhead during this time, so I removed the streaks it created in a few frames with Photoshop’s spot healing brush.

    I saved the edited versions as jpegs and then opened them in software appropriately called StarTrails. The software builds the image one exposure at a time, and it is interesting to watch the process. I have a pretty powerful computer, but it still took about 20 minutes to create the final rendering using the finer of the two blending modes.

    I made a few final adjustments in Photoshop to create the image you see here. U.S. Highway 41 skirts the north shore of Lake Michigamme, so headlights from the few passing cars did a nice job of highlighting just a bit of the fall colors in the trees. The faint green glow on the horizon is a distant display of the Northern Lights.