We had an unusually heavy fog recently and I went to Blendon Woods metro park to photograph it. I brought along a battery powered LED light I usually use for macro photography and had some fun light painting.
I attached the 10 stop ND filter and set the camera to manual and the shutter speed to 20 seconds then adjusted the ISO and f-stop to get a slightly underexposed image. The first thing I tried was dragging a string of little red LED’s along the path, but they just aren’t bright enough to show up in a long exposure.
Next I did a test with the big LED light. It’s a Neewer CN-160 – a battery powered, 160 bulb, 600 lumen light that’s roughly equivalent to a 60 watt incandescent bulb. It showed up very well. It was held behind my back as I jogged down the path. Because of the long exposure and because I’m moving fast and wearing relatively dark clothes, I don’t show up at all in the photos.
After a couple test shots I increased the exposure to 30 seconds and adjusted the ISO and aperture. The only ND filter I have that fits the lens I used is a 10 stop. To get the depth of field I wanted meant using an f/8 aperture. To balance the 10 stop filter and f/8 I had to bump up the ISO to 320 to get a 30 second exposure. Thirty seconds gave me enough time to make it around the bend in the path. By the time I walked back, the camera was finished doing the long exposure noise reduction. If I do this again, I’ll bring the diffuser for the light. When the light is close to the camera you can make out the light trails of the individual bulbs.
Click images to enlarge. All photos are copyrighted and protected by Digimarc.
ISO:320 – f/8 – 20mm – 30 sec – 10 stop ND filter
I did 16 runs and varied where I held the light and what part of the trail I followed. Jogging a path in the fog holding a light behind my back and counting to 30 – that’s not weird, is it? All sixteen shots were loaded in to Photoshop, converted to a Smart Object and the blending mode was set to ‘Maximum’. Maximum selects the brightest value for each pixel from all of the layers. All sixteen was too much. The light trails are too widely spaced and the highest trails block the view of the path going around the corner.
ISO:320 – f/8 – 20mm – 16×30 sec 10 Stop ND Filter
I picked the best six shots and composited those in to the final image then adjusted the white balance, contrast and color before finally adding some vignetting. If I try this again, I think I may set the camera the same and attach the light to something so I can hold it closer to the ground.
ISO:320 – f/8 – 20mm – 6×30 sec – 10 Stop ND filter