Posted on : 03-24-2014 | By : Andy | In : tech
Tags: alpha keyer, church video, imag, lower thirds, propresenter
(Note: this is the sixth post of a series on how to do iMag without a megachurch budget.)
Video is nice and all, but adding on those ever-popular lower-thirds graphics adds a bit of panache that makes your video stand out as professional, and not home-hacked. It’s also incredibly helpful for visual learners, and for underlining important content that shouldn’t be missed. We use them for word definitions, key points, and the text of supplemental scripture passages.
Thankfully for us, the ATEM Television Studio includes support for 1 upstream and 2 downstream keys. Definition time: keying refers to taking a video feed and cutting out parts of it based on color, luminance (brightness), or a separate feed. An upstream key happens first, typically, (think the weather guy in front of a green screen) and a downstream key is added after all video compositing is finished (think lower-third or logo bug). They both work more or less the same.
We started with a chroma key, as it’s super simple. Using ProPresenter, we set the background of our presentation to a bright magenta. (We chose this over green simply because our content was more likely to contain greens rather than magentas). This output went directly into our TVS using one of the HDMI inputs.
When we activated the upstream key, we set the chroma key to cut out anything magenta, which let the video of our pastor show through. This was OK, mostly. However, because of some problems, we eventually shelled out the money to upgrade to the “proper” solution outlined below. Those problems?
- The most ‘fool-proof’ method of using this key was to leave the key turned on during the whole service. Unfortunately, that meant that if we played back any video or other graphics through our system that included colors close to that precise shade of magenta, those parts of our slides would become transparent and show our video through them. Not great.
- The alternative method was to only turn on the key during the preaching portion of the service. However, if the operator missed turning on that key, the moment we went to the slide intended to be keyed out, a bright-magenta screen would show up instead. Since we usually show a pre-sermon intro video, this window was rather small. We had some purple screens show up, and that wasn’t nice. Furthermore, for some reason I had a hard time training our volunteers to understand the key well enough to ensure they wouldn’t screw it up again in the future. *sigh*.
- ProPresenter fades all of their transitions, even the swipey ones. When a graphic faded out, the magenta behind it would essentially grow brighter and brighter as it disappeared. Unfortunately, a chroma key is only so effective, so there was always a brief flash of dark purple on our screen right before the magenta got bright enough to be recognized as the key color. Our best solution was to make the fades go really fast (or use cuts), but that was very jarring and not ideal.
- The solution to our purple flashes would be to use PowerPoint or Keynote to run your slides, which could animate a slide-in motion of your graphics without fading. But we like the features of ProPresenter, and we paid a lot of money for it, so we weren’t going back to the stone ages of PowerPoint.
So what did we end up doing? ProPresenter has an add-on product that costs more than the software itself. (Yes, it’s stupid. No, there’s nothing we could do about it but pony up the cash.) For $1,000 you can get an “Alpha Keyer Module” that allows you to set ProPresenter to create two simultaneous outputs: one “Fill” that contains the graphics you want to show, and one “Key” that tells the switcher what parts of the screen to show, and at what transparency level. What stinks is that it only works on a Mac. What stinks worse is that it also requires you to have an extra piece of BlackMagic hardware that retails for about $1,000. I found one used on eBay for $600.
The great news is that once it’s properly configured, ProPresenter does all the heavy lifting. You plug in your UltraStudio 3D or UltraStudio 4K with a thunderbolt cable, and connect the two outputs to two of your SDI ports on your TVS. We set one of our Downstream Keys to use those two feeds (Fill and Key), and we can leave it on all the time. No purple involved, no human switching involved. We can use nice long fades and it looks absolutely beautiful. Expensive, but super-worth it. (Note, however, that leaves us with only 2 SDI feeds for cameras. There are still 2 HDMI feeds you can use if you need them.)
Tip: For some reason, Renewed Vision recommends turning on Additive Blend in your settings for ProPresenter. Don’t do this. You can follow their instructions here, but leave the Additive Blend box unchecked. On your Downstream Key on your ATEM, make sure “Pre-multiplied Key” is checked.
Bonus tip: If you’re not using the Alpha Keyer, or if you’re having issues switching between HDMI sources, try an ConnectPRO HDMI EDID Ghost. When we were plugging our iMac directly into our switcher for graphics, there were some issues involved with the HDMI “handshake” that gets negotiated when you connect and disconnect displays, especially if we turned on the Switcher after the Mac was already on. The EDID Ghost is a little box that accepts an HDMI in from your computer and sends HDMI out to your TVS. It copies the handshake of your TVS and fakes the computer into thinking it’s always connected. You can turn your TVS on, off, disconnect it, or even use an HDMI switch or splitter to send that signal to other devices as well, and your iMac will never know the difference.
Next up: Live Streaming