The ATEM 1 M/E Constellation HD Live Production Switcher (1 RU) is the entry model in the HD Constellation line, delivering live-event HD switching from up to 10 individual 3G/HD-SDI inputs in a 1RU chassis. It supports both 3G-SDI and HD-SDI signals, with programme output via six 3G-SDI BNC outputs or a webcam output via USB Type-C. A multiview output gives up to 16 routable windows, able to display inputs, keyed video, graphics and stills from the media pool alongside the programme output, and each input connects to a built-in Fairlight audio mixer supporting up to 28 channels of audio. A reference video input is built in, and every input carries its own frame synchroniser, frame rate converter and format converter. Keying runs to 4 upstream and 1 downstream keyer, with chroma and luma keying plus colour and pattern generators, and the switcher can be controlled as hardware or via software for Mac and Windows.