Thunderstorm

This Summer we already had several thunderstorms crossing my city but either it happened at a time when I was in office or I was busy with other, more important things. This was very frustrating to me, because I love hunting lightning strikes, as I already mentioned in a former post.

Yesterday evening a non-forecasted storm came closer to the city. First I saw those huge dark clouds and soon they were also some flashes within them. The thunderstorm was moving very slowly, so I had plenty of time to get my camera and tripod ready. It was late in the evening and quite dark which is good for achieving long exposure times. After choosing an area where I expected to happen most lightning strikes I've set up my camera to continuous shooting. Every now and then a flash appears, but not very often. I immediately reviewed the last taken photo to check if I catched the strike. After about an hour with the storm coming closer slowly the was a bright flash suddenly. Again I checked the just taken photo and was amazed. What a beautiful lightning strike did I catch!

29mm  f/4.5  15sec  ISO100

For those of you who are interested I will explain how I do try to catch lightning strikes. I used my EOS 600D camera and chose the standard zoom kit lens with 18-55mm focal length. Using a lens with standard zoom or wide angle gives you the chance to frame a larger part of the sky. The key in catching flashes is long exposure time. I tend to use some between 10 and 30 seconds. Since flashes occur unexpectedly and last fractions of a second you are not able to release the shutter just in time. That's why I switch my camera to lowest possible ISO value, which is 100. This reduces image noise and enlarges shutter speed. Both is very welcome here. Then I switch the camera to shutter priority mode, which is Tv mode at my Canon. Depending on daylight situation I adjust shutter speed between 10 and 30 seconds. Aperture is calculated automatically. Luckily, in a city there is always enough light to get autofocus working. Even at night. So I adjust the focus with autofocus first and switch to manual focus afterwards. All the following shots are taken with this one focus setting. Furthermore I disable image stabilization which is recommended when the camera is mounted to a tripod. A tripod is essential with those long exposure times. To not miss any second I setup my camera for continuous shooting. By using a remote control with lock feature I can permanently press the release button and thus take photos continuously. With these settings I maximise the chance of catching a lightning strike.

Catching one flash is one thing. Post-processing the image is another. When using semi-automatic mode during night time you will always get quite bright images with usually a too warm color temperature. Furthermore, aperture is calculated on a night scene, but flashes are very bright, which usually results in overexposed areas. To get a more dramatic result I turn the color temperature to some lower and colder value. This results in a more blue shaded scene. I darken the image to increase the night feeling and reduce overexposure of the lightning. With adjusting the white balance I darken dark areas and brighten bright areas to increase contrast and intensify drama. From the original frame I crop out a frame that brings the lightning strike to best attention. At last, re-sharpening the image gives the final touch. To demonstrate all these post-processing steps, here is the original, un-edited photo of the above shown scene. (The dotted line is a departing airplane.)

29mm  f/4.5  15sec  ISO100

For rounding up today's post I present two more lightning strike from yesterday's thunderstorm. They are by far not as dramatic as the one above, but I also like them very much.

29mm  f/4.5  15sec  ISO100

29mm  f/4.5  15sec  ISO100

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