A green screen can give you greater control over how your image appears in mmhmm. Learn how to use a green screen with mmhmm and enhance your image quality.
Green screen types and settings
You can use two types of green screens with mmhmm: virtual or physical. The virtual green screen is selected by default, but if you have a physical green screen, select I have a greenscreen in the Camera settings menu.
Green screen in-app setup
- In the bottom right of mmhmm, click the Camera settings dropdown menu and select I have a greenscreen.
- Set the threshold percentage to dictate the sensitivity of green screen detection so mmhmm recognizes the darker and lighter areas of your green screen. Adjust the range of hues that match your background using the threshold sliders. Experiment with the upper and lower bounds until you have a crisp silhouette.
Light your foreground
The existing lighting in your room should be sufficient for mmhmm, but lighting your face with other sources of light can further improve the quality of your image.
Generally speaking, studio lighting concepts translate well to mmhmm:
- Ideal studio lighting illuminates a subject with soft, diffuse lighting from multiple angles to eliminate hard shadows.
- In a typical three-point lighting setup, the main source of light (the key light) is set at an angle to one side of the subject. A second, softer light (the fill light) is used on the other side of the subject to fill in the shadow caused by the key light. The larger the difference in light intensity between the key light and fill light, the greater the shadow.
- A third light is sometimes used to light the subject's hair and shoulders from behind. This enhances a subject's silhouette and can make them stand out from the backdrop or green screen even better.
- Fabrics are placed over the lights to diffuse the light. By increasing the surface area of the light source, the light is "softened" which creates a more flattering lighting effect. To achieve this diffusion effect, studio lights are placed in softboxes or bounced off silver-coated umbrellas or through white, translucent umbrellas.
Even without professional studio equipment, these concepts can be used to combine the natural and artificial lighting in your environment to replicate these effects. For example, a desk lamp bounced off the cover of a book can be used to greatly enhance the lighting quality of your image.
For more lighting tips and types of lighting to improve your video, watch the following video.
If you're looking for a light, consider the Elgato Key Light Air.
Fix green outline when using a physical green screen
This green outline is called a green screen spill and can be reduced with the following steps:
- Shine more light on yourself instead of on the green screen behind you.
- Adjust the green screen threshold while working with your lighting.
- Crop your image in your video conferencing tool if you have a smaller green screen to work with. For example, you can use the slider in Zoom to zoom in to your image.