My partner, Mike Perkins, has a new blog post up:
The world is moving in the direction of HDTV, but NTSC “standard def” signals are still common for many reasons and will remain so. One important reason is that cameras that output NTSC are widely available and cheap! Many applications, including a lot of security applications, simply don’t require the resolution of HDTV…and don’t want to incur the camera cost and bandwidth hit it requires.
So, what is resolution anyway, especially with regards to an analog NTSC video signal? Analog video cameras, especially in the CCTV industry, are sold using “horizontal TV lines”, or HTVL, as one of their key specifications. Unfortunately, the math behind that concept is not well understood.
Read the rest of Perk's post at the Cardinal Peak blog .