Tape vs. Digital Video Recorders
There are two main ways to record video images that your CCTV cameras capture; they are analog tape and digital video recorders. The vast majority of analog video recorders use VCR tapes and either standard VCR’s to record the images or special security time-lapse VCR’s to record images for a longer period of time.
VCR Tape Recorder
A tape recorder such as a security-time lapse VCR can record CCTV camera images in either black and white or color for either 2,4, 6, 8, etc all the way up to 960 hours which is 40 complete days. The determining factor is how many frames per second you intend to record and how many cameras you have hooked up to your VCR for recording. For instance, if you record 30 frames per second (real time video), you will only be able to get a few hours of video captured on your recorder. If you record one frame per second or less, you can record for dozens of hours before the video tape is full. VCR’s are very practical, very reliable and extremely affordable. Expect to pay only a few hundred dollars for a security VCR.
Digital Video Recorders
There are two types of DVR’s (Digital Video Recorders). They are either stand alone devices or hard drives that are connected to a computer system. DVR’s work similar to VCR’s except the images they capture from the CCTV camera is digital. The amount of digital images you can capture on a DVR is determined by a few factors including the frames per second recorded, the amount of cameras hooked up to the DVR device, the resolution that the DVR saves the images at and the video compression used (e.g. MPEG4). For a common set up, where you have 4 cameras shooting at 30 fps and you use an image resolution of 320 X 240, each camera only records when motion is on, and you use MPEG4 compression, you should be able fill up a 20 to 25 GB hard drive in about 80 hours.