Streaming Media

Streaming Media on Facebook Streaming Media on Twitter Streaming Media on LinkedIn

Tutorial: How to Set Up a Single-Operator Live-Switched Stream with PTZ Cameras

Pan-tilt-zoom (PTZ) camera systems are now hitting a sort of renaissance for event videography, especially in live concert, government, and worship settings. This tutorial looks at how to use a PTZ-based workflow to pull off a multicam live-switched stream with a single operator at the controls.

Camera Optics

Let’s start by looking at the optics. The HEA10 (Figure 3, below) is described by Panasonic as a “control assist” camera. It’s not necessarily meant to be used as a standalone camera, although its feed can be recorded via HDMI.

Figure 3. Panasonic’s AW-HEA10 control assist camera

This control assist is designed to be used in conjunction with one of Panasonic’s other PTZ cameras and its PTZ Cntrl iPad app. Once the iPad joins a shared Wi- Fi network, the interface displays both the HEA10’s video feed as well as the feed from the PTZ camera it’s paired with. The HEA10 shows a fixed 95-degree wide-angle view of the scene. From here, the operator can simply pinch to zoom, tap, and drag to pan or tilt and even record and recall preset camera positions. Pairing multiple HEA10s with PTZ cameras gives the user the ability to manage multiple groups of cameras quickly and easily using the same application.

Using this system can be an ideal training session for an operator that finds a hardware controller a bit overwhelming at first. Even getting on-the-fly shots of unexpected events is made easier by allowing the operator to quickly tap the area of interest and have the camera move immediately to that region.

The second camera in my test kit was the AW-HE40SW (seen in the background of Figure 1). This is the white SDI version of Panasonic’s smaller PTZ cameras.

When most people picture a PTZ camera, they probably envision something that looks very similar to the HE40. It matches the traditional “dome” style of many security cameras. It also resembles an extra-large telescope (like the Giant Magellan Telescope currently underway in Chilé) in the way that it pans the entire top housing and tilts only the center section.

This 1080p camera features onboard recording that can be enabled and disabled via a browser interface. In fact, all of Panasonic’s PTZ cameras can be accessed and controlled remotely via a web interface. This doesn’t replace a multicamera hardware controller, but it does give you an emergency backup. Additionally, the HE40—and the other two cameras used in this test—support power over Ethernet (PoE+), reducing cabling requirements.

The final camera used for this article was the HE130K (foreground in Figure 1). If the HE40 looks like a giant telescope, then the HE130 looks like a wildlife photographer’s telephoto lens mounted on a gimbal head. Comparing the pricing of the HE40 (MSRP $3,450) and the HE130 (MSRP $8,500) reveals a good reason for the disparity. The HE130 features three 1/2.86" HD MOS sensors to the HE40’s single 1/2.3" HD MOS sensor. Because of this, the HE130 features superior low-light functionality and overall quality.

While the two can successfully be used together without significant differences in image, the HE130 can be used strategically based on these and other advantages. For example, the HE130 may be best for low-light audience reaction shots, as it will have much lower noise with a large aperture or gain. Both cameras record up to 1080p60.

Controlling the Cameras

To operate these PTZ cameras, Panasonic sent me its AW-RP120 (Figure 4, below). This behemoth can control up to 100 cameras over IP while also offering all the shading and color controls that a camera engineer would want and expect in professional camcorder systems. Detailing all of the features of this camera controller would take an entire article by itself, so let’s look at the basics for our scenario.

Figure 4. Controlling the PTZ cameras with the Panasonic AW-RP120

The lower right and lower left sides of the controller contain the most frequently used areas: the joystick for pan and tilt on the right, and the rocker and knobs for zoom, focus, and iris on the left. As a longtime PTZ user, the joystick control is often the make-or-break component for me. If the camera movement can’t pass as natural and smooth, it’s virtually worthless. At the very least, it severely limits the possibilities available to a production. Viewers don’t expect to see jerky camera movements on a live program, and there’s no reason they should have to.

The RP120 features a large joystick with what I would describe as a medium-firm feel. It’s not too easy to move it around, and it gives the user enough resistance to make easing into and out of moves simple. Speed adjustment is conveniently located right next to the joystick, making slow creeps or swish pans just a flick of the wrist away.

Zoom is performed with the ubiquitous rocker switch found on all professional cameras. Even the zoom and focus controls feature their own speed adjustment knobs. The focus speed adjustment is limited to the autofocus when it is toggled on. Both the focus/iris/zoom controls and pan/tilt controls can be disabled completely with master toggle buttons to prevent any inadvertent changes once cameras have been set to exact positions and settings.

The AW-HS50 compact live switcher (on the right in Figure 2) combines the familiar feel and operation of a traditional hardware switcher with a space-saving 7x8.25" footprint. The typical cut/fade/wipe transitions are included, but this tiny switcher also includes features such as picture-in-picture, user presets, keying, tally light control, and multiview output over SDI or DVI.

Related Articles
At $5,399, the Canon N500 is a bargain compared to other 1" sensor PTZ video cameras. Featuring 4K/30P and NDI|HX2 support, it has a long 15x optical zoom lens and dual XLR audio inputs, and supports the low-power POE+ standard.