Creating the Cliffhanger
- • A brief history of the green screen technique
- • Choosing a concept that works with green screen
- • Suspending the model with climbing ropes
- • Placing the green screen material background
- • Putting the green FlexDrop in place
- • Posing your model to conform to the substitute background
- • Achieving realism with lighting techniques
- • Isolating and clipping out the subject
- • Placing the subject onto a new background
- • Tips for merging photo elements
- Olympus E-5
- Olympus Zuiko 12-60 mm
- BackDrop: 10 x 20-foot chroma green
- BackDrop: FlexDrop®2
- Constellation®3 large SilverDome® kit
- LiteDisc® accessory: LiteDisc® holder
- LiteStand Accessory: Boom
- LiteStand Accessory: BoomStand
- LiteStand: large
- SilverDome nxt: medium
- StarLite® QL
- StarLite®: medium digital kit
- DedoLight DLH200D with Barn Doors
- FlexDrop®2, a folding screen with a reversible blue and green surface.
- Chroma Green cloth background measuring 10x12 feet
- Chroma Green cloth background measuring 10x20 feet
- Focal Length: 17 mm
- Aperture: f/3.5
- Shutter Speed: 1/100
- ISO 250
- Focal Length: 14 mm
- Aperture: f/2.8
- Shutter Speed: 1/125
- ISO 250
- DedoLight®
- StarLite® in Medium SilverDome® back light
- Constellation®3 fill light
- StarLite® in Medium SilverDome® key light
- All Lights
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Do you ever take shots of wild adventures? Would you like to take a photo of a mountain climber clinging to a rope 1000 feet above the ground? You can do it! Photographer David Cross shows us how to merge a studio shot with an outdoor location using ‘green screen’. The green screen technique is so common in motion pictures, advertising and video game production, we don’t notice it any more. It’s the technique that enables images to be merged with one another in realistic looking, yet impossible scenes. For those of us that take the time to learn the process, it opens up creative possibilities that have been the sole domain of Hollywood directors. This lesson reveals the secrets to this interesting and useful technique in a simple step-by-step process. Have fun! (Click on any thumbnail image below for an enlarged view.) |
Topics Covered:
Equipment Used:
Camera/Media
Lighting Equipment
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What is "Greenscreen"? Greenscreen and bluescreen background dropout techniques began around 1940 as a way to achieve special effects, like having The Thief of Bagdad fly on his magic carpet. The approach is essentially the same as it was then: A special colored background (intense green or blue) is placed behind a subject. The subject must not contain that same color. In post processing, the special green or blue is removed from the scene, leaving the subject free to be placed upon another background. We see this technique used by television weather presenters every day. The weatherperson is actually standing in front of a large green wall and the weather maps (backgrounds) are added electronically. Photoflex® manufactures three products for the chroma key process: |
Figure 1 |
Figure 2 |
Figure 3 |
To get started, Jaron and I prepped the studio with the chromakey backdrop. Because I needed my model, Lisa, to look as though she was hanging from a rock, we took down our traditional backdrop setup in exchange for the bare wall of the studio. Using about twenty push pins, we secured the backdrop to the wall. [figure 3) |
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I made sure to mark where on the wall the wooden support columns that held up the sheet rock before the backdrop was 100% in place. Above where the backdrop would hang, I drilled a hole into the support column and screwed in a large eye bolt that I picked up at the local hardware store. I made sure this hook was extremely secure, as my model's weight would rest solely on that hook. In addition to the main support hook, I screwed four more bolts into the wall to act as hand and footholds. I sliced small holes in the backdrop fabric to allow the bolts to poke through. [figure 4] |
Figure 4 |
Figure 5 |
On the left side of the set, Jaron unfolded a FlexDrop®2 and mounted it onto a medium LiteStand and a LiteDisc® Holder. [figure 5] The FlexDrop®2 would act as a background on the side of Lisa when I decided to shoot at an angle other than straight behind her. For the best result, it’s important for the greenscreen background to remain as flat as possible during shooting so the special green color is easily selected and deleted in post processing. The FlexDrop®2 background does that quite well because the wrinkle free material is stretch-mounted onto a metal frame to eliminate dark and light areas that can hinder the masking process. Additionally, FlexDrop®2 is very lightweight and can be easily repositioned to conform to various model posing. |
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I secured the climbing straps to Lisa and mounted her to the wall while Jaron and Jeffery finished setting the lights. [figure 6] |
Figure 6 |
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To light Lisa, we initially chose two StarLite® fixtures and a Contellation®3. Our key light would come from a StarLite® with a 1000watt bulb boomed overhead and to the right. Our fill light, the Constellation®3 with two 1000watt bulbs on, would serve to both fill in shadows behind Lisa but would also light the FlexDrop®2, making post production much easier. Finally, to give some separation, we mounted a second StarLite® on a boom and boom stand up above and behind the FlexDrop®2 as a hair light. [figure 7] Both booms were counterbalanced with RockSteady bags filled with sand. |
Figure 7 |
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Our model and lights in place, I prepped my camera. I chose my Zuiko 12-60 mm and my Olympus E-5. I stepped back and stood directly behind Lisa and instructed her to use the eye bolts and act as though she were climbing. [figure 8] For this shot, my camera was set to the following: |
Figure 8 |
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Now I know it doesn't look like much yet, but trust me, once we get this into post production it will all start to come together! Lisa was definitely looking like she was climbing from this angle, because she was supporting herself in the same way she would have been on a rock face. Notice that the lighting is quite soft. That's intentional because the background we'll be using later for this shot was photographed on an overcast day. It is essential that both photos have the same kind of lighting if the final image is to look natural. [figure 2] |
Figure 9 |
For the next shot I moved over behind the boomed StarLite® on the right side of the set and stood on a step ladder to get a better angle on Lisa. From this angle I planned to capture an image that would fit one of my background choices. I compared a print of the proposed background to the angle and lighting of this setup. I asked Lisa to make some minor adjustments so her feet would conform to the outline of the rock formation. [figure 1] Though I knew a real climber would rarely find themselves in such a position, I asked Lisa to sit back in the harness and hold on to the rope. Sure it was impractical in the real world, but it was a flattering position and I liked how it was looking. [figure 9] |
Figure 10 |
I took a test shot to see how I liked the lighting here. [figure 10] |
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Though it was looking pretty close to what I would need for the backgrounds I had chosen before the shoot, both Jeffery and I felt that we needed a hard light to help mimic the sun on the back of her head. Jaron took a DedoLight® focusing lamp with barn doors and mounted it to a large LiteStand to get it up as high as the boomed StarLite®. He then focused it into a beam that would cast over the side of Lisa's head and give us that sharp hard light we were looking for. [figure 11] |
Figure 11 |
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Even as Jaron was still focusing the DedoLight®, I could tell it was making a big difference. With the addition of something so simple, we were very much closer to creating a perfect lighting scenario for the pre-selected background. [figure 12] |
Figure 12 |
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Once the DedoLight® was perfectly in place, I took a series of photos from this angle until I had one I was really happy with. [figure 13] From this angle, my camera was set to- |
Figure 13 |
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I really liked this result. Her pose was nice and the light looked believable given my pre-chosen backgrounds. To help illustrate why we needed four lights, I took progression images showing each step in order: [figure 14] |
Figure 14 
Figure 15 
Figure 16 
Figure 17 
Figure 18 |
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To emphasize the difference of using the hard light from not using it, compare the following. [figure 15 & 16] Each of the two back lights is performing a different duty. The StarLite® does an excellent job of giving soft coverage along Lisa's back and separates her from the background. The DedoLight® is a far more focused beam and only covers a small area. However, it acts much like how the sun would outside in the middle of the day, casting hard, high contrast light. |
Figure 19 |
Figure 20 |
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The next step was to take my results back to my office and form composites with the background images I had already selected. |
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The first step in creating my composite was to extract Lisa from the background. I used a combination of the quick selection and the pen tools. [figure 17] |
Figure 21 |
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Once Lisa was selected, I just extracted her onto a transparent background. [figure 18] |
Figure 22 |
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I then took that layer and dropped it onto my background and resized Lisa to a believable size. [figure 19] |
Figure 23 |
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Though her size and position were believable, I still needed to adjust the curves and contrast balance to fit the background. Because she was so well lit in the studio, it was easy to adjust the levels. I masked a layer and selectively darkened Lisa. [figure 20] |
Figure 24 |
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For the second image, I followed the same initial steps as before using the Quick Selection Tool and Pen Tools to extract Lisa. I then placed her on the chosen background. [figure 21] |
Figure 25 |
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This composite didn't look believable for more reasons than the differences in quality of light, contrast, and color temperature from the original scene. My photo of Lisa would need more than simple adjustments of contrast and curve levels, it would require me to create accurate shadows that would have occurred naturally.
First, I created a duplicate layer and overlaid black onto it. I then adjusted the feathering on the edges and the opacity to create a shadow. [figure 22] |
Figure 26 |
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Though better, it still didn't look quite right. To fix that, I took another layer and burned in some shadows all around the rock formation to create a light pattern that matched the lighting on Lisa as well as the rock formation. The result looks best as a full frame image where Lisa is smaller in the frame, not just because it minimizes the paste-up, but also because the scale of the photo is more interesting. I also noticed that the final image looked more natural on some monitors that others, depending upon how they were adjusted for color and contrast. |
Figure 27 |
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With that, I ended with my two finals. [figures 24 & 25] |
Figure 28 |
Figure 29 |
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That does it! I hope you enjoyed this lesson and consider trying green screen composites yourself. I don't profess to be the know-it-all when it comes to this technique, but I certainly know more now than I did when I began this project. If a commercial job requiring a green screen photo came along now, I'd know how to explain the pitfalls and merits of the process to the client. I can also imagine many possibilities for this technique in future projects. --- Photographed by David Cross Post Production by Deborah Ortiz Assisted by Jeffery Jay Luhn and Jaron Schneider Modeled by Lisa Spencer |