HD CCTV Recorder Buying Guide

The DVR should be able to accept the same signal type as the cameras you are connecting to it. Some DVRs are Hybrid, which allows them to connect to both HD/Analogue and IP CCTV cameras, these Hybrid Recorders are also known as XVRs.

The DVR determines the resolution and quality of your recordings. The recorder can support higher resolutions than your cameras, however the cameras will still record at the maximum resolution they can output.

The number of camera inputs you require on your recorder will be determined by 2 factors:

1. How many cameras are you connecting to your recorder?
2. How much spare capacity do you need for adding additional cameras to your system?

In our experience it is always good practice to have 2 camera inputs spare for every 2 cameras you have on your system. So for example if you will be connecting 4 cameras buy an 8 camera recorder so you have room to expand your system in the future.

When looking at recorder specifications you will notice that fps is often mentioned. This is an abbreviation for Frames Per Second. A DVR's recording rate is measured using this format.

For example if a 4 channel DVR records 4 cameras and has a recording rate of 25FPS per channel. This means that the recorder will record 25 frames a second from the camera. The best way to think of a frame is as a still picture, so the recorder is recording 25 still pictures from the camera every second. When these are viewed, they will give you smooth real time video, without any gaps in the footage. If the recorder was recording 1 fps (frame per second) then when the recording was viewed it would be like viewing still images not a smooth video, and 96% of every second of recorded footage would be missing!

The best frame rate is 25fps and in an ideal world all systems would record at this. However the higher the fps and resolution the more processing power and recording space the recorder will need, so different recorders have different limits on how many fps they can record each camera at.

See our recommendations for fps below:

Application	Ideal FPS	Lowest FPS
Identification or High Risk (such as cameras located in premises that serve alcohol or handle cash)	25	15
Recognition or Medium Risk (business premises)	15	10
Observation or Standard Risk (homes)	10	5
Detection or Low Risk	5	1

There are four factors that will need to be considered when you choose the hard drive size in your DVR.

1. The video codec type of the DVR - Older DVRs use the H.264 codec which does a great job of compressing the video file size so extended recording times are possible even on smaller hard drives. However the very latest codec, H.265, offers comparable picture quality but with half the file size.
2. The recording frame rate of each camera - The higher the frame rate (fps) each camera is recording at, the more storage space it will require.
3. The recording resolution - The higher the resolution the more storage space is required.
4. The activity level if recording on motion only - All of our DVRs have motion detection as standard, this allows the DVR to record only when there is movement in the camera scene. For example a motion activated camera used in a business environment typically has motion for 50% of a 24 hour period, so it will be recording for 12 hours compared to 24 hours continuously. A camera in a residential application will typically record for 25% of a 24 hour period, so 6 hours.

On the product information page of all of our DVRs you will see a Storage Space Requirements Table which will show you how many TB of recording space is required depending on the above factors.

Some applications will require special features to ensure that you get th most from your CCTV system.