Shooting on a Chromakey

Are you bored with shooting the same old identical poses on the same old identical backdrops? You have heard “Blue Screen” could be the path for you but you just art not sure how to get started and don’t what to invest a fortune to get started.

I faced a learning curve back in the early days of this technology through trial and error. Today the entire process is simplified through the use of Photoshop , processes and/or plugins as well as stand-alone applications. First lets put the meths to rest and explore the process to a quick and successful digital background swap.

The color Blue or Green makes little difference although green is quickly becoming the trend today. I use both, but also use Black and white more often then not. The original thought was that both blue and green contain less colors that conflict with skin. As cameras progressed in technology green became favored because of fewer conflicts with clothing. Any backdrop can be used with some careful planing it’s sometimes more advantageous to use one over the other, but we will explore veracious situations later in this article..

To Make Life Simple on Yourself, Flat Lighting is Essential.
Flat lighting is essential because shadows on the background will effect your final results. This could give way your look of realism and destroy the effect of the background. If you have practiced for years to never let the light from your main fall onto the backdrop, you will need to retrain yourself. Uneven lighting may result in other shades of the background color, which may not be extracted accurately.

In the diagram to the left you can see how I gridded my Beauty Dish for directional control, then feathered the the softbox to spill directly on my backdrop. I still have dark, harsh shadows falling on the backdrop, so an additional strobe with a 7″ reflector and barn doors is needed. The barn doors are to help with in the reduction of light from hitting the back left of my model. This would be a typical White, Blue or Green screen setup for me. I am not as concerned with shadows hitting a Black backdrop, which I usually use for work intended to be night scenes.

In an Ideal Situation

In an ideal situation I’m going to put some space between the background and my model posing in the foreground. Generally I like to have 6′ to 10′ between the subject and the Chroma-key backdrop. This will eliminate the background color spilling onto your subject, Color Reflecting back on the subjects clothing and hair. I’ll light the backdrop very flat and evenly with large softboxes. Using my flash meter, I’ll over expose the background 1/4 stop. This is important because I will loose that later with the added distance. Now with some working space I will turn off the background lights and light my model as I normally do. Once you’re happy, turn on the background lights and shoot away. A lot of people tell me to put as much distance as possible between the subject and the background. This is not required. You only need to eliminate the color from spilling over on your subject. White clothing will reflect more color, blondes will reflect more color. Pay attention!!

It’s important to have a plan or at least some general idea how the finished shot will look with the new background, so that you light your model to fit the scene. Most Background swaps fail because the lighting on your subject does not match the lighting in the surrounding finished photograph.

The Eight Golden Rules to Chroma Key Success:

  1. Light the background as even as possible. I like to use 2 strobes at a 45 degree setup.
  2. Pull muslin backdrops tight to remove as many wrinkles as possible. This will make your life easier in the long run.
  3. Set your camera’s white balance of flash, not auto. Hot Lights will require adjustments!
  4. Distance your subject from the background to avoid color spill. This is especially important with blondes, who’s light hair will naturally reflect color.
  5. Turn off the background lights, then light and pose your subject as normal. Keep your final photograph in mind. It will look fake if the sun is in the background to the right and your subject is lit from the left. Try to anticipate your hair light to mimic the sun, etc.. Backlights can be very tricky and may require some experimentation.
  6. Do whatever you must to compose your subject without feet. Shooting with Chroma Key’s become extremely difficult once you start painting in shadows from legs and feet.  Especially with irregular surfaces, such as sandy beaches, etc.
  7. With all lights turned on shoot.
  8. Take the time to learn your Plugin. All of the plugins mentioned below have slightly different characteristics and preform slightly better or worse under various lighting conditions.

Photoshop is not required:

Before I get into the processes and plugins I use I should point out there are some very effective inexpensive programs that will give you outstanding results without the need for photoshop. While I use Photoshop for my work a Google search for Chroma Key Applications and Plugins should reveal a complete list. I would advise trying several until you find something you are comfortable with.

As I mentioned earlier Photoshop plugins provide a very high degree of accuracy and simple to use. You can remove a background without third party plugins. Removing a background or anything in Photoshop starts by creating a Mask. How accurate you wish to be is dependent on the time you wish to invest in any given project. You should review my Quick Mask tutorial or Google Masking in Photoshop.

What I like about the Plugins is the accessory and detail. If properly lite you can remove the background while leaving a single strand of hair. This would be next to impossible masking in photoshop without a third party plugin.

Adobe recommends Primatte Chromakey 3.0 in the Extension exchange, I have tried it and found it a bit overly complex, but excellent. With the ability to do Black, White, Green and Blue. Its priced at $199.00
I really like (and own) The Green Screen Wizard, it’s simple and very accurate. It has the ability to remove Blue and Green backgrounds. The Photoshop Plugin starts at about $199.99. They also offer several stand-alone versions which are very simple to use, but good luck moving it to a new machine or recovering from a hard drive crash!!
A friend gave me MaskPro by OnOne from my birthday. This is not a Chromakey plugin, but this Plugin ROCKS! It’s very effective for doing fine detailed masking and background processing work, its a real lifesaver!! What i love about this plugin is you can select the background color to remove or the foreground color to keep. Then you simply erase the other. I have used this on some very diffacult and poorly lit images. It took me about one minute longer then the Green Screen Wizard (had I shot on a chromakey).

The Screen itself:

Chroma Key backdrops come in a verity of shapes and sizes. I don’t go anywhere without a 5’x7′ Flexy Blue/Green Chroma Key in the car, because you never know. 🙂 I use a 9′ roll of green in my Sacramento studio and a 12′ roll of blue in my San Francisco studio. I’m told by some video friends that they prefer green for several reasons. It really makes little or no difference to me, but I seem to prefer the blue for other reasons.

I have found companies that make chromakey body suites, boots and gloves, tape, the possibilities are limitless. As for the digital backdrops. E-Bay has so many its sickening. I usually make my own…

Have fun 🙂

Professional Models used in this article: (from top down) Jessa Garlets and xo Danielle and should be contacted directly for booking inquiries.