EXPERIMENTS WITH FLASH
by Flo Deems
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List of equipment and supplies used:
- Nikon D300 camera body
- ISO: 250
- White Balance: Auto
- Aperture: f/5
- Mode: Aperture Priority
- Flash Mode: Regular
- Focus: Manual
- Nikkor SB900 flash gun, set to TTL
- Nikkor SC-29 flash extension cord
- Nikkor 50mm 1.4 lens
- At least 2 vases, blocks, books, etc, about 8 inches high (about 20 cm)
- A clear sheet of picture frame glass, to place on top of the vases
- 2 sheets of white copy or typing paper
- Small plant sprig
This is an account of one of my flash experiments in which I tried to back-light a sprig from a plant. I set up 3 glass vases of sufficient height to allow the tethered Nikkor SB900 flashgun to lie beneath on its backside with its head bent upwards. I used the Nikkor SC-29 extension cord, which allows the camera to send a focus light in low light. The other cord models do not allow this. Over the vases I placed a sheet of clear glass. On the glass I placed the small plant sprig, a type of coarse grass. Over that I put a sheet of white copy or typing paper.
Next, I put a Nikkor 50mm 1.4 lens on my Nikon D300 body. The flash was set to TTL. ISO 250. White balance, Auto. Aperture set at f/5. Camera was set to shoot with Aperture Priority, which means it selects the shutter speed. I set the focus for manual.
Standing on a chair, I attempted to shoot the paper hoping to get shadows of the plant. Trial and error produced many unsatisfactory compositions. One big problem was that the flash cord pulled the flashgun off center slightly, resulting in an unevenly lit piece of paper. The other big problem was that since I couldn't see through the paper, I had to guess at where to aim the camera.
But one time my finger accidentaly hit the Preview Button on the camera's front, which caused the flash gun to light up--and lo and behold, I could see the silhouette. Since the light stays on only briefly, I had to compose quickly. But the percentage of decent compositions rose. A nice trick to know about!
The results surprised me. Wouldn't you think that I'd get a black and white, or gray and white silhouette? But instead, the power of the flash gun was strong enough to go through the leaves to register their green color in the images! So I switched the White Balance to Flash, and then got sepia-toned silhouettes, instead of green.
I selected one image and took it into Photoshop CS3 and diddled with it. After converting to a sepia tone, I duplicate the image with a blur layer. Gaussian blur set to 57. First I moved the blur layer, so there are 2 images with different placements of the "shadow." I did not crop these. Next I moved the blur layer back to register with the sepia image and tried out different blend modes. Below are the original image plus the 7 images resulting from my playtime in CS3.
Please click on the images to see a larger version.