HD-CCTV Cameras: Cheap quality live video for DATV
HD-CCTV Cameras: Cheap quality live video for DATVIn my quest for high quality DATV (Digital Amateur Television), I learned a lot experimenting with the HiDes DC-100-B-01 HD-CCTV DVB-T modulator/camera, the subject of an earlier post. With a good lens, it gives an excellent DVB-T signal at up to 1080P. It is a modified HD-CCTV SDI camera with a DVB-T daughter board modulator with a 50 Ohm BNC output that go to cable or to an amplifier then antenna.
Using the BlackMagic Design ATEM TV Studio, I could use SDI cameras. Box-style, HD-CCTV cameras, with inter-changeable "CS" mount lenses and SDI digital and analogue output cost less than $150 on eBay. A bargain! Most use Sony image sensors.
The cameras have a composite output that allows setting up the digital video even H.264 compression.
The catch! The purpose of HD-CCTV video is to allow high definition video to allow clearer inspection of suspicious activity. As such, and perhaps to avoid extra circuitry, they are not interlaced, with both 720P and 1080P. 720P is fine, it is a standard DVB-T format, but 1080P isn't and won't be recognised by the ATEM TV Studio. As such, it is only possible to use them directly on 720P, but at least at a range of frame rates.
The selection of lenses for HD-CCTV is important for quality at high resolution. The optical quality of the lens needs to be as good as, or better than the camera's resolution. Most CCTV lenses are for SD (Standard Definition) and not suitable for the HD-CCTV. The industry has standardised on this problem by using the term "Megapixel" for the optical high definition lenses.
HD-CCTV cameras use a "CS" mount, but with an adaptor, can use "C" mount lenses, commonly used for 16mm movie cameras. So it is possible to get quite good lenses for them.