Your webcam feed is one of the most important aspects of a high-quality presentation. This article covers our tips for getting the most out of your camera setup.
While mmhmm will work with the built-in Mac camera, we recommend using an external HD webcam. External HD webcams will have a higher image quality and have the added benefit of greater control of your recording angle.
- If you're using a physical green screen, note that the larger the field of view of your webcam, the larger or closer a green screen needs to be to completely fill the frame. For this reason, wide-angle webcams (typically those with 110° fields of view or greater) will need to be placed closer to you if you are using a physical green screen.
- If you own a DSLR, it may be possible to use it as an external webcam. With this approach, you can use your DSLR lenses, which can produce a richer image and be more suitable for some types of broadcasts.
Green screen types and settings
You can use two types of green screen with mmhmm: virtual or physical.
The virtual green screen is included with mmhmm and requires no special setup. It automatically detects the position of your head and body in the foreground and separates it from your background, allowing you to take advantage of mmhmm's rooms, or backgrounds.
Physical green screens are usually made of a green fabric and hung from a stand or frame in your physical environment. Frequently used in Hollywood and online streaming, the bright green of these backdrops makes it easier to digitally superimpose the subject in a virtual scene. While these require a bit more effort to acquire and set up, they are currently the best way to make the subject "pop" in a virtual room.
You can change select your greenscreen type in your camera settings, found in the top right corner of mmhmm.
The default is the virtual green screen, but if you have a physical green screen, select "I have a green screen".
Green screen color - by default, this is set to the color of most commercially available green screens, chroma key green. If you are using a monochrome backdrop that isn't chroma key green, you can use the color picker to select a color closer to the color of your backdrop.
Threshold - when using a physical green screen, you can toggle the sensitivity of mmhmm's background detection with the threshold slider.
Lighting your foreground
The existing lighting in your room should be sufficient for mmhmm, but lighting your face with other sources of light can go a long way in improving the quality of your broadcast.
Generally speaking, studio lighting concepts translate well to mmhmm. Here are some of those for you to consider for your own setup.
- 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, or the key light, is set at an angle to one side of the subject. A second, softer light, called 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 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/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," creating a more flattering lighting effect. To achieve this diffusion effect, studio lights are placed in soft boxes 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. Even something as simple as a desk lamp bounced off the cover of a book can be used to greatly enhance the lighting quality of your broadcast.