First Greenscreen

Shareece & James - Photo by Blackburn Images

My son and his girlfriend were going to a prom recently and I’d offered to do some photos for them. I got the idea to try my hand at some greenscreen (chromakey) photography. This is where you photograph the subject in front of a green or blue chromakey background and then replace the background with an image. In this case the prom theme was “ red carpet affair” so I thought it would be cool to show the couple on a red carpet with paparazzi in the background.

I ordered an inexpensive green background, received it the day before I “needed” it, and went about trying to achieve some respectable results. A quick search on the web showed that the main elements to successful greenscreen shots is a wrinkle-free background, very even lighting on the background, and keep the subject a good distance away from the background to avoid getting green “spill” light back onto the subject.

In my first tests, I used only one off-camera flash (SB800) to try and light the background. My goal was to light it, but not so much that a lot of light reflected back off to the subject. I couldn’t get very even coverage with the SB800 so I tried a single strobe (White Lightning x800). Again, not very even coverage so I opted for two White Lightning x800 for the background through white umbrellas to diffuse the light. My flash meter said I was pretty evenly light across the background. I light the subject with another x800 with a 30x40 softbox directly in front of the subject and as high as my eight foot ceilings would allow it go. I set the main light to be about 1.5 stops brighter . My tests shots were still showing some green spill onto the subject, but I had to background lights down to their minimum power and the subject as far in front of the background as I could with my limited space (6 feet from subject to background).

The shots of the “real” subjects (4 couples) came off pretty well. I still got more green spill than I wanted on the subject. I used Photoshop (select/color range) to select the green background to drop out. I still had to do a good bit of “clean up” around the edges (layer/matting). I also tried the OnOne Mask Pro plug-in (Plug-in Suite 5) to see if it did a better job. I was a little disappointed with the Mask Pro results, but that was probably due to my haste in not defining enough drop colors and keep colors. I had some of the pixels in the black tuxes masked out.

Just like everything else in photography I’ve tried you can get results pretty quickly, but to really master a technique takes time, study, and practice.