In the video world over the past 20 years there have been many, many different types of cables and connections used to pass signal from one medium to another. From composite video to VGA and DVI, and now to SDI and HDMI. But while we have heard of these cables, you may wonder what are they? And what do they do? Today we’re going to talk about HDMI and SDI. In future articles we will talk more about passing video signal over Cat6a cable using HDBaseT. If you are wondering what that even means, just keep a lookout for the upcoming article to learn all about it. ;)
Let's start with HDMI cables! HDMI stands for High Definition Multimedia Interface and is the most frequently used HD signal for transferring both high definition video and audio over a single cable. Really, it's pretty amazing! HDMI is typically used for connecting devices such as TV’s, wireless presentation devices like an AppleTV or huddle space integrator like Klik Boks, and is generally considered a consumer level video cable. It's easy to find HDMI or mini HDMI in an average home today on computers, tv's projectors, etc. One of the big advantages with HDMI at the homeowner level is simply that it is a single cable solution for combining both video and audio. It has replaced many of the analogue solutions which required separate video and audio cables creating a tangle of confusing wires in spaces that were supposed to be easy and uncomplicated for the average person to use. One of the big disadvantages to HDMI cable is that you can only run most HDMI cables up to 25’. Though this isn't generally a problem for the consumer, it can create difficulties in other areas.
Our other popular Video Cable option is SDI. SDI stand for Serial Digital Interface. What does that mean? SDI is a standard video signal used by professional, broadcast grade cameras. SDI cable has the ability to transmit HD video signal over a much farther distance than HDMI. SDI also has the ability to pass audio as well. SDI cables are made up of two components, 75ohm coaxial cable and BNC connectors. Now, not all SDI cables are the same. Different cables can carry different quality signals over specified distances. Just because one cable fits or is long enough, doesn’t mean it will work at all, or even that it will work properly! The higher the quality of the video signal you are sending, may require you to either go a shorter distance with your cable or you may need to use a higher grade cable. In a later article we are going to discuss SDI video signal, the different quality, and some of the solutions that SDI offers.
Video cabling can be more complex than audio cabling and it's important to have your expensive and sometimes sensitive equipment connected properly. If it's not, it can cause you all kinds of problems and glitches or produce a poor quality video. Cable is cheap in comparison to video equipment, so take the time to see if your problem can be fixed with an easy cable switch before giving up on your gear. We hope you are learning more about cables! If you have specific questions you'd like to see answered, email or find us on social media!
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