Stars around this planet

Tonight, the sky was exceptionally clear, especially for summer, and I trekked (well, drove) down to Jordan Lake to see what I could capture. Jordan Lake is about the only place in the area with largely unobstructed views and relatively dark skies, and that “relatively” is key – there are too many cities nearby pumping light up into the sky for really good night views.

Nevertheless, I managed to capture a first for me, believe it or not: a detailed stretch of the Milky Way. This picture has been enhanced slightly from the original, correcting the color cast a bit and increasing contrast, because digital doesn’t work as well as film on the night sky. This was also taking a chance, because I’m aiming mostly south here, which is not the best move from the Northern Hemisphere – the stars to the south show the most apparent movement, and smear across your photo frame more. This is a mere 26 second exposure and movement is still visible in the full res version. For further specs, this is ISO 800 at f2.8.

The stars at the bottom of the photo, curling around and upwards to the right, are the constellation Scorpius – look for the two pairs of close stars. The pair towards the middle of the frame are the “stinger,” and the other pair is the base of the tail leading into the scorpion body facing towards upper right. Portions of Sagittarius are peeking in from the left, which would make, I believe, the center of the Milky Way Galaxy appearing towards the top left of the frame. It isn’t apparent from our position, because too much dust obscures our view. And somewhere in there is a massive black hole.

One of these days, I’ll do a beach trip during good weather and get out on the shore during really clear nights. The Outer Banks has lots of areas well away from city lights, and of course, half of the horizon is ocean and free from light pollution. When I do this, I now know I’ll need some decent high speed film to get results like this. Alternately, I could construct a tracking platform that counteracts the rotation of the earth, tilting the camera slowly to keep the sky “unmoving,” which allows for very long exposures without star streaks. This plays hell with the horizon, of course, and for most of those shots you’ve seen where the horizon is sharp and the sky is intricately detailed, the horizon has been patched in digitally afterwards. Film and digital sensors just don’t handle the sparse light from the night sky in short exposures, and most especially without grain or noise. ISO 800 is far from ideal – I usually shoot 100 for detail and color rendition, and some films I use are rated at ISO 40 – that’s less than 1/16th as sensitive to light as ISO 800, and so the exposure time would have to be much longer: seven minutes! Yeah, you get some pretty heavy star streaks then.

At some point later on I’ll go into the trials of long exposures, pushing film, and reciprocity failures. Dim light photography has all its own body of knowledge, almost making it a specialty in itself. I’ll warn you adequately so you can skip it if you like ;-)

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