Wednesday, July 22, 2009

In the Still of the Night

I was playing out on the deck the other night at about 9:45 and came up with this image. Naturally the camera was on a tripod, but there is no unusual filtering. We'll be heading out to do some night photography in the next couple of weeks and I wanted to work out any kinks in the methodology well before leaving. I will admit to color correcting the image, but it was exactly the same workflow I use on daylight shots. What I see is three different light sources, with two color temperatures. The lights on the posts are solar powered LED lights. At best they give a soft glow when viewed in real time. Here they appear to be high illumination, powered lights. The next light source is a street light about 150' away. A tree stands between street lamp and the wall of the house, casting the mottled shadows on the wall. It shows the relationship of light temperatures between the white of the LEDs and the warm, reddish color of the incandescent street light. The third source lights the sky. It's light pollution from the center of town about a mile away. The reason for the red glow is the same as for the mottled light of the rear wall. The street lights and, probably, the lights in most of the buildings are the same incandescent type found right outside along our street. I may have to do something about showing this image to the town fathers and asking them to reduce the town's electrical bill by going to more energy efficient bulbs. Well, that explains the experiment. If you'd like to know more about the night photography project, hit the "read more".

Before getting to the project I'll have to explain a little about night photography. It is a little bit of "by guess and by golly" photography. There are a couple of traps to watch for and things to remember. First would be that it ain't like daylight photography. There's no grab shots in night shooting. You have to do some preplanning and you might want to bring a tripod, some sort of remote release, a flashlight, a chair and an adult beverage. You're going to be awhile. It doesn't hurt to be able to visualize what the camera to doing without needing to put your eye to the viewfinder. Trying to look through probably isn't going to help a lot anyway. It's also helpful to understand hyperfocal focusing. That's where the flashlight comes in. You may want to put a red filter over the business end of the flashlight so you don't wreck your ability to "see" in the dark. The red filter won't effect your "visual purple". Chances are you don't want to wait a half hour after each time you light the flashlight to be able to find your camera. Sort of counterproductive.
Back to the original intent of this post. If you understand where the "in focus" range for a given focal length falls you'll be able use the flashlight to help set the focus using the focus ring on your lens. (Make sure you have the lens on manual focus, any vibration reduction off.) "Most" night photography falls into the wide angle category. If you're looking for star trails or a big ol' moon you'll get into longer focal lengths, but "most" will be wide. So, we're at a small focal length. Something like 18 or 24mm. If the camera is on a tripod, set to a "normal" height and you use a small F-stop (F11, F16, F22) your shortest focus distance would be about 6' or 8' in front of you. You "should" have everything in pretty sharp focus. If you're down low to get the rocks at the edge of the water you have an different set of focusing problems to deal with.
Now, sit back, get comfy and have that adult beverage. You're on the bulb setting for your shutter speed. Make sure whatever way you have your shutter release set up you follow that routine. If you can click to start the exposure and click again to end the exposure, great. If you have to hold the release to keep the shutter open, make sure you use your non adult beverage holding hand. You can start making your exposures. With the lens stopped down you're going to be a while. One thing to keep in mind is that the write time to get the image onto your memory card is going to be just about the same as your exposure time. If your exposure is one minute, as in today's image, your write time will be about one minute. A five minute exposure would have about a five minute write time. Ten minutes = ten minutes. One hour = one hour. You can see that you won't be getting a lot of shots. You might as well take the camera off that high speed shutter, it ain't gonna help. There's other things to think of, but this is starting to get to be a ramble.
The project is to get some decent, salable shots. Simple as that. I'm thinking no one will be paying for a print of today's image, unless your my wife (wait a minute, she won't pay me either. rats!) The immediate purpose is education. I'll figure out how to sell something later.