Night photography can be pretty cool. During the day, generally speaking, the human eye sees more variations of color and shadow than your camera, hence the reason for HDR and all that. At night, the camera has the ability to accumulate light and color over time, which your eye can’t do, so in a way it sees more. I don’t do enough night photography, but I got out the other night for this.
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I was pretty pleased, reviewing on the camera. Pleased enough that I forgot about the downsides. Doing things in the dark is just difficult. I generally like shooting things a bit farther away, because it’s really hard to tell what is and isn’t in focus. If you have more distance between your camera and the beginning of your subject, it’s easier to get enough depth of field to get them all sharper. I did bring along a flashlight to check focus up close, but… it becomes a pain. I also stepped in a lot of goose shit. That’s just how it is. This being Greenlake, I wasn’t even worried about getting mugged for my backpack full of camera lenses. All was good, right?
Well… yes until I got home and saw a line of blue across all my shots:
All. The. Way. Across.
You don’t see it in the panorama above because they have all been laboriously removed in Photoshop. After I found the problem, I immediately shot a few more pictures with other lenses, batteries, whatever – I wasn’t happy about this. They’re all the same, including with the lens cap on. Any aperture, ISO speed, whatever. I did some research.
If you want to get technical, this is called a stuck pixel or maybe a whole row of them. It is slightly different from a hot pixel, which would be white all the time. All that matters is it is going to ruin my pictures. The internet is rife with folk remedies about taking off your lens, setting your camera to manual cleaning mode (where the mirror flips up) for a few minutes and then turning it off and reattaching your lens. Maybe it works for some people, but it didn’t do anything for me.
Since hot or stuck pixels (at least a couple of them) are nothing new, there are some other options out there. Some cameras have options to use a dark frame (basically a picture taken with the lens cap on which should contain light only on the problem pixels) to cancel out the noise in the good frames. The theory is that since the bad pixels are always in the same place, you can map them and work around them. I’ve yet to find any software that works correctly with my camera and since I’m a few weeks past the grace period on Canon’s warranty, I’m still unsure what happens next. I see a lot of healing brush in my future!