What is an ME &
Do I have a 5 ME switcher?
If you, like many over this last year, are new to pro video switchers, their terminology, and features you may be wondering about ME’s. ME’s are where the magic happens in video switchers and are comprised of controls each with a row of buttons for Preview and Program.  Program is the video source you are sending out and Preview refers to the video source you are intending to transition into next.  
Let’s start by talking about what ME stands for. An ME stands for Mix Effects Bus.  To understand what this is we will break down each word. First, we can start with M or Mix. Mixing is the combination of two or more elements.  At its most basic function, a video switcher does just this by mixing different sources such as multiple cameras or a GFX source.  
Next, the E refers to Effects. In a switcher Effects mainly relate to transitions or how you mix them.  Some effects are referred to as a Cut which is a simple changing of sources for your visual. This could mean switching from one camera source to a second camera or from a camera source to media. You can then mix a gradual change or dissolve between the two sources or even apply a quick wipe or shape movement between sources. You could also use a DVE, which we will get to in another article, or use a Fade which is a transition to or from black.  
Lastly, Bus is a term borrowed from audio. We can think of it as a funnel or pathway for video.  So, in essence the Mix Effects Bus is the place where you make choices on video camera or graphics sources by using effects. 
Do I have a 5 ME switcher? Most likely not. Switchers usually come in 1, 2, 4 ME flavors.  
Why would I want more than one ME?  The answer is nesting and effects.  Generally, in a video switcher you can create something on a higher number ME and then bring that up for use in a lower number ME.  An example of this would be cutting cameras in ME 2 and then cutting between your camera’s bus and your graphics in ME 1. You could also use this to add a small overlay box like the ones you generally see on the news showing cameras cut over graphics.  
Some switchers also have something called an aux bus.  An aux has no preview/program and no transition effects, so it’s mainly used for sending a single source such as a computer to a projector while your ME is used for your livestream.
Ok, so thanks for all that, but how do I star wipe? Well, there are some rules for switching that make things generally more pleasing to for the viewer to watch. We suggest keeping things simple for now: cut between cameras and dissolve to or from graphics.  Why? Because it is how our eyes and brain process things naturally. Cutting is a natural break similar to blinking and dissolving helps to signal our minds that we are changing to something totally different.
Enjoy this new terminology and we hope it helps you get to know your switcher.  Ryan, Lambda’s owner, came from a broadcast video background at PBS. When he was being trained on video switchers, he had to complete a test that required him to use only ME’s and internal switcher feature to build a mostly complete American flag in the switcher without the use of any graphic sources.  Think you can do it? Tell us how you did it on your switcher and maybe there is a free t-shirt in it for you!