I find myself well past the point of no return on the rocky road of live stream video. There are, of course, experts in this subject, and businesses built around providing streaming services for corporate meetings and educational venues. If you willing to pay (or charge) upwards of $5K a day for a team, go for it. Working alone or with at most one assistant on a tight budget is on the challenging side. I am strictly mobile, going to where the work is. Nothing comfy like a studio, more like a table in a corner. I'm not touting any particular brand or model. I hope to relate which features I find most important, and some idea to the stumbles and solutions I found on the way. I can do UHD and DCI 4K, but HD is best for live streaming at this point in time. Streaming is like a podcast, but in real time. Everything has to work right the first time around. You get a second chance with a delayed broadcast, but you lose the immediacy of the event If you use multiple cameras, you need a computer with multiple inputs, or a video switching device feeding a single adapter or laptop. All the cameras and switching devices must be set to exactly the same resolution and frame rate! If you can't see a signal, read this line again. The computer must re-package the video signal for streaming, and transmit the results. I use Wirecast for this task, on recommendation from others. For HD, you also need a fast connection to the internet. Wired is best, but WiFi will work if you can reliably get 6 MB/s upload speed (10 MB/s for a safe margin). If you want good sound, microphones on the camera won't do. They're not in the right position for good pickup, and camera microphones are hardly the best choice even if you could detach and move them. I do mostly classical music concerts and contests, which typically employ between 4 and 8 microphones. In addition to feeding a stereo mix the video stream, each microphone is recorded on a separate track, so you can really polish it up for delayed broadcast (or production). It is best to use SDI connections for video. This is thin, shielded cable with locking BNC connectors at each end. Runs can be as long as 100 meters (328 feet) for 1080p60 video. HDMI is limited to 15 feet, the cables are stiff and unwieldy, and the connectors are easily dislodged. Nearly all professional cameras have SDI outputs, but HDMI to SDI adapters are relatively cheap ($50) for HD video. SDI signals can be easily split and sent to multiple destinations, such as monitors and recorders. The switcher is the key device in the signal chain. You send one camera to the output, with another camera cued up for a switch. The transition can be a cut (instantaneous), cross-face, or any number of creative variations called wipes. The best choice would be a hardware panel, with all the buttons, lights and gadgets in easy reach. However hardware panels are large, heavy and expensive - impractical for mobile operations without a box truck and riggers. You also need a multiview monitor, showing what's on each camera, what's playing and what's cued up. My first switcher was a Black Magic ATEM Studio Pro 4K. It's great, in that it does everything I need, and can be controlled by software or a hardware panel. The connection is by ethernet cable, so the computer/controller can be a long way off (but usually sits on top of the box, which also contains a monitor panel). Two problems. I found I can't run the switcher and Wirecast on the same computer. It takes too much time to switch screens, and Wirecast can get dicey if it doesn't have your full attention. Secondly, buttons on the virtual panel don't coincide with those on the multiview. You have to look and think twice before pressing a "button." Buttons on this ATEM itself don't serve a useful function. They control an auxiliary output, without any multiview or transition options. My second iteration is an ATEM Television Studio HD, but a simpler version which serves as controller and switcher in one. There are four HDMI inputs and four 3G SDI inputs, for a total of eight useable ports. Buttons on the panel are red for live and green for cued, and correspond to the multiview. Unlike the new ATEM Mini, this one has a multiview output, which can be any TV or monitor screen with an HDMI or SDI input. I'm using an Atomos Shinobi, 5" monitor intended for on-camera use. Everything fits in a small case, ready to deploy. However, neither can be rack-mounted, and rack cases are a lot easier to transport and set up in the field. A third iteration looks promising - an Atomos Shogun 7. This is a portable monitor/recorder with a 7" screen, battery operated, with a removeable SSD hard drive. The Shogun 7 has one HDMI and four SDI inputs, and can switch those inputs to a single SDI or HDMI output. Each channel can be recorded at the same time as the output (switched) channel. A 1 TB SSD would give you about 1 hour of five channel recording. In addition to two audio channels for each camera, there are two balanced (XLR) analog inputs. Switching is via a touch screen, with various transition options. Recorded in this way, all the video and audio channels are synchronized - a huge time saver when editing. The 3000 cd/m^2 is bright enough to see in broad daylight.