Southbound Storm

I took this photo last night and uploaded it to my Facebook page this morning. Thanks mainly to the guys at Higgins Storm Chasing who kindly shared it, it got a large number of comments, like and shares. Lots of people have asked about the processes behind this photo so I thought I’d do a little walkthrough of the whole process.

The Scene

I love storm chasing. I love photographing nature when it’s cutting loose. I particularly like photographing electrical storms with lots of lightning. Last night I was relaxing watching a movie when my son pointed out that there had been several large flashes of lightning outside his window. I went out onto my balcony and waited and sure enough a few minutes later there was a big flash of lightning some distance to south. Pausing only to kick myself for not spotting it earlier, I headed out to see if I could get some shots of the storm.

I always keep my camera charged up, in the car and ready to go. No harm has ever befallen it and there are many occasions where I’ve been able to capture a scene I’d have ordinarily have had to leave to the iPhone. So I didn’t have to worry about getting everything together apart from spraying plenty of Aerogard on before heading out.

I set up next to the public wharf here in Shoalhaven Heads because I like the strong foreground interest the structure creates. I setup the tripod and pushed the legs down into the sand to make it as stable as possible and then put the camera on and pointed it in roughly the right direction.

The Camera

The settings for shooting night photos vary slightly from camera to camera, but the basic rules are the same. You get as wide an aperture as your lens can allow, you set the ISO to as low as you can get away with and you expose for upwards of 20 seconds. My 550D suffers a bit from noise in higher ISO settings so I try and keep it at 1600 at night – 3200 if I really must. If you have a newer or full frame camera then you’ll be able to get away with higher settings.

I shoot pretty much everything with my 10-22mm superwide and its maximum aperture is f3.5,  so that’s what I set it to. This ensures you get as much light through the glass as possible without having to rely too much on the electronics. If I was just shooting stars then I’d have plumped for a 30 second exposure, but since I wanted to capture lightning strikes I set it to 50 seconds instead.

Now you may be wondering how I set my camera to a 50 second exposure when pretty much all DSLRs max out at 30 seconds before bulb mode. The answer is that I have a custom firmware in there called Magic Lantern, which enables me to set pretty much any exposure length I like. I’ve found that 50 seconds is a good exposure time because it enables me to capture a series of correctly exposed images and then move to another spot if required. I used the same settings on my photo of the storm over Black Head, below.

Storm at Black Head

The only other dial setting  you really have to worry about is white balance – and if you’re shooting RAW (which is highly recommended) then you don’t even have to worry about that. Cameras have a very hard time setting white balance in the dark so I tend to set mine to Tungsten which is always a good starting point – you can always warm it up or cool it down further in post.

So then there’s the focus. Sometimes it’s possible to focus using a light in the distance but I usually simply focus to infinity and then wind it back a fraction to just before the little notch. I’ve never had an out-of-focus image using this method, but if you’re concerned then turn on your camera’s liveview mode and use the zoom to focus more precisely.

The Exposures

In this image I wanted to do a couple of things. Firstly I wanted to photograph any of the lightning strikes and secondly I wanted to get some star trails in there. For this reason I decided to shoot a series of exposures in the same spot with a 50 second exposure time. This combination would give me a great chance of capturing a lightning strike and even if I didn’t get a strike then I was recording star detail that would merge into trails later.

I do own the awesome Triggertrap remote trigger, but I didn’t use it for these images. Instead I simply set a two second delay (to allow the camera to be as still as possible) and a Magic Lantern exposure time of 50 seconds. I took my exposures with only a second or two gap between them. Once I was sure I had plenty of lightning and plenty of stars I moved and set up again in a different location.

The Post Processing

Combining night shots can sometimes be very easy, but often there are some details you’ll need to fix before the finished composite is ready. I import my images into Lightroom and perform basic tweaks them. I get the white balance looking right, I increase contrast slightly and adjust highlights and shadows as necessary. When I’m happy with them then I use the Export to Layers function in Lightroom to get it all into Photoshop.

With my images in Photoshop I change the layer mode of all but the bottom layer to Lighten. This stacks the images on top of each and creates the composite star trail effect. Often there are elements of the individual image layers that need to be removed. To do this I simply create a mask and paint out those bits I don’t want. When I’m happy with it then I flatten the image.

Since I shoot with a super-wide lens at 10mm there’s often a considerable amount of distortion that needs to be dealt with. The Adaptive Wide Angle Lens filter in CS6 is perfect for fixing my images, it enables me to correct perspective, straighten edges and get the whole composition looking its best.

With perspective corrected I then do my sharpening in Photoshop, perform noise reduction and add final effects such as vignettes to create the finished image. Finally I make sure the horizon is straight, clone out any sensor dirt or light leaks and then save the image back to Lightroom.

In case you’re interested – this is what the wharf looks like during daylight from roughly the same angle.

Shoalhaven Heads Public Wharf