Setting up a good key can be hard sometimes. Here are some basic steps that you can use to help you with keying using your Roland switcher.
THE SCREEN
- Always try and find the best quality green screen.
- Good Keying always starts with a solid even background.
- There are various scenarios where you would use a portable green screen background, some of which involves fabric.
- If you are using a fabric green screen make sure that the fabric doesn't have wrinkles, stains or the obvious tears.
- For permanent painted background installations of course just make sure the maintenance on green screen is kept up.
- Have extra paint in case you need to touch up the background before your shoot.
THE LIGHTING
- Before putting your subject in front of the screen first you have to make sure that the background is lit very well to ensure the green is bright and even.
- Overhead lights illuminating the back ground is recommended.
- Check if lighting is even on a background using a waveform vector scope, or camera's zebra pattern setting.
- The Zebra tool will allow you to see if you have hot spots (overexposure points) on your background.
- After adjusting lighting, you should see an even zebra pattern on the camera's LCD screen.
THE SUBJECT
- Make sure that your subject is far enough from the background that you don't cast a shadow onto the background or worse have green from the lighting reflect on your subject.
- This will vary depending on the space you have to work with.
- For head and torso shots a safe distance is about 5 ft-10 ft.
- If you want a full body key then you will need a larger space and add more lighting.
- Subject lighting should not be as bright as it is on the green screen background.
- That will create hot spots on your subjects face and hair.
- An overhead light should face the subject lighting the face, hair and upper body.
- A floor light facing upward or towards your subject to light the arms, legs and lower body.
- Lighting the floor helps avoid a shadow casting on the green screen floor.
CONCLUSION
So these are some basic tips to help you achieve a better key. I hope this helps you with you production. Make sure that you give yourself plenty of time for setup. A good setup and test run will give you the best results on your production.