Even Canon’s own excellent C300 professional HD camera, which was released way back in 2011, utilized a sensor which captured 4K for certain colors, and then strategically reduced that resolution later on in the image processing pipeline.įor various technical reasons better explained by an electrical engineer than a guitar player, this process produces an image which is generally more detailed than that produced by HD cameras which employ only HD-capable image sensors. Many of the best HD cameras, like the much-vaunted Arri Alexa used nearly ubiquitously on Hollywood and television productions, benefit from capturing images with greater-than-HD levels of detail. In fact, you may be surprised to learn how it is created in the first place. So it’s clear that not all HD is created equal. Their smudgy image may be flattering for closeups, but often fail to deliver that “you are there” feeling on detailed wide shots like you’ll get from an NFL broadcast. Even held steady on a tripod and filming a static subject, DSLRs like the Rebel are lucky to deliver 720 lines of actual resolution, regardless of the number of vertical lines in the files they record. It’s just that consumer cameras, regardless of format, are often neither. They are also occasionally Full HD broadcast as 720, further complicating comparisons, but nevertheless preserving some of the hyper-detailed look of the original footage through intelligent downscaling algorithms. Television sports are still, for the most part, Full HD. And while 720 is indeed greater than the 480 vertical lines of SD television and DVDs, and thus, still defensibly “high-definition”, the difference between consumer 720 and professional 1080 will be obvious to even a casual observer who compares their weekend soccer practice footage with the hyper-detailed look of the typical high-definition sports broadcast. The more detailed 1080 version of the HD format is referred to euphemistically as “full HD” in videography parlance, presumably to leave some marketing wiggle room for the 720 format to share the HD moniker. In fact, despite their branding as “HD” cameras, previous generation DSLRs like the ubiquitous Canon 5D and Rebel lines don’t actually deliver 1080 HD-levels of detail, but rather something closer to 720 vertical lines of resolution. Though it was introduced over three years ago, the GH4 still delivers what you’d consider a cutting-edge picture when it is properly exposed, and particularly when its 4K output is downscaled to a more broadcast-friendly 1080p HD, as we did for our livestream: For our master studio shot, we used one of the best of the current generation of full-frame, 4K-capable mirrorless cameras, the Sony A7S II:įor the closeup shots, we employed two Panasonic GH4s, a smaller “micro four-thirds” sensor camera that was one of the first to bring a 4K image and video-centric feature set to the prosumer market. I'm at a bit of a loss as to how to troubleshoot this.As with microphones, preamps, and converters in audio recording, the resulting video quality of any live broadcast will depend greatly on the quality of the video signal you feed it. Initially I thought this might be a frame rate issue, but I have the identical frame rate set on all components - TVS is set to 1080p59.94, as is the mimoLive document, the SDI playout configuration in mimoLive and the output on the Ultrastudio HD Mini. (Note: graphics do not freeze in mimoLive, they continue behaving as normal). To recover, I have to restart mimoLive on the Mac. If no graphics are active, trying to play something like a lower third doesn't appear at all on the TVS. If a lower third is active when this happens, for example, the lower third remains on screen. My problem is that after a period of time (sometimes as little as 5 minutes, sometimes as long as 20 minutes) the Fill/Key signal on the TVS freezes/stops working. Setting the Upstream key to ONAIR works as expected - graphics output from mimoLive is superimposed over the image from the current active camera. I have Upstream Key 1 set to Luma with Fill set to the SDI A signal and Key set to the SDI B signal from the Mac. MimoLive outputs fill and key signals on SDI A and B out on an Ultrastudio HD Mini into two of the SDI input channels on the TVS. I have a TV Studio HD receiving input from mimoLive running on a Macbook Pro.
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