TIPS & IDEAS AROUND CHOOSING AND INSTALLING A CONSUMER CCTV SYSTEM
What I didn’t anticipate is firstly that CCTV is actually a relatively active community online. I’m not sure why that came as a surprise as that’s true for anything online but I guess that I’ve always seen CCTV as a tool to do a job. Without that creative element, I figured the information and opinions online would be limited.
Secondly, I completely underestimated the regulation and legal aspects of CCTV. Again, a silly mistake as experience of filming the shortest sequences in public and being approached by security guards should really have made me think that installing multiple 24/7 cameras might have some regulation attached.
Today, I’m looking at my newbie experience in the world of consumer CCTV and the tips, recommendations and suggestions I can make to you if you’re a consumer thinking about buying and installing a system. It’s a bit of a minefield in some respects so I hope you find some of this useful.
THE SYSTEM I BOUGHT
DON’T FORGET THE LAW
I don’t want to dwell too much on this one because I am not qualified in anyway to advise you on the facts. You can buy a system very easily but using one legally is a little more complex. If you’re in the UK, the ICO is your best starting point for this. Be wary trusting people online who state ‘facts’ about the law. You’ll see a lot of phrases thrown around like, “this is clearly a breach of data protection.” when the reality is very different.
In the UK at least, these are the types of questions that you should be sure you consider.
- Why are you installing CCTV?
- Is data protection an issue?
- Do you need signs to notify people?
- Do you need to pay to register as a data controller?
- Should you consult with your neighbours?
- How are you going to secure your data?
- Do you actually need CCTV at all and would alternative measures be more appropriate?
Now, I have absolutely no doubt that hundreds of thousands of cameras are installed around the world with no consideration around this whatsoever. If you’re on a property in the middle of the countryside with no-one for miles around, I can see why these kind of questions may feel less relevant. I guess my tip is just be aware that this legislation exists. It will make you much more able to address any questions and concerns from people and it just feels right to do your homework and not play ignorant.
HAVE REALISTIC EXPECTATIONS OF YOUR SYSTEM
Most consumer CCTV systems consist of x number of cameras connected to a DVR recording in a compressed format to a hard drive. It’s a very simple idea which is good for reliability. Something I noticed when researching systems is that people have unrealistic expectations. We’re in consumer territory here and with that comes the usual corners cut relating to equipment, cabling, power supplies and most importantly optics of the cameras. As cameras go, these are budget cameras. A box may advertise HD or even 4K but don’t be won over by simple specs like this. There is so much more involved in getting a good image and so many areas where it can fail.
If you’re like me and are spending £400 on a 4 camera analogue system (a mid-price consumer system), for what you’re getting, this is excellent value in my opinion but not necessarily the quality that some may expect.
Let me give you an example.
BASIC SENSORS & OPTICS – The sensors on cameras like this are tiny and lenses are simple in their design. They cannot always resolve huge amounts of small detail. You may not be able to identify a car reg plate at 20 metres which might seem unacceptable to some. If that’s you, you might need to accept that you need to invest more.
DYNAMIC RANGE – The dynamic range on the cameras and image processing on the DVR is also limited. If your camera is looking at an area that may be partially in bright sunlight and partially total shadow, you may find that during the brightest times of the day, you struggle to resolve detail in both areas. It will either be too dark or too light. This is totally normal for a camera of this type.
It’s definitely a case of finding the system that provides the best bang for your buck even if none will perform miracles.
OPTIMUM CAMERA PLACEMENT
CLEANING CAMERAS – Having cameras accessible from the ground is bad from a security standpoint but having them accessible from inside somehow is incredibly useful. You will want to wipe the lenses regularly to ensure the best image quality possible.
I guarantee that you will have a cobweb across one of them within days of fitting up the cameras. This is not a massive problem in the day but as soon as infrared kicks in, you have a piece of web reflecting light right next to the lens. This blocks the view of the camera but also consumes bits in your data stream. A huge moving object on a frame is very difficult to compress so your bitrate on that camera will shoot up (assuming you’re using VBR…more on that later) reducing the retention of the system. The quality of the rest of the image will most probably degrade as a result of the recording being ‘starved’ of bits.
MOVING CAMERAS – You may well change your mind or need to change your mind due to local objection or legal reasons. Fit your cameras well but try to keep options open. I guess what I’m saying it, don’t rebuild your roof to have a stand to mount cameras on. Try to keep the process as simple as you can to reverse.
WATCH THE LIVE VIEW WHILE FITTING – Test the view and framing through the system up to the final tightening of the screws. They will shift about and rotate as you fit them.
AVOID AUTO-EXPOSURE PROBLEM AREAS – Avoid including bright white walls or direct lights in the frame if they’re close to the camera. Let’s say your camera is pointing down a path and a third of the frame is filled with the white wall of your house, this will appear as a very bright object to the camera and confuse the automatic exposure in the day and potentially ruin it at night.
AVOID GLASS – Never position your cameras behind glass looking out unless you never intend to use the infrared. It will bounce straight back and swamp the sensor of the camera.
CONSIDER PRIVACY – Finally, and not really a technical aspect but consider the privacy of others when placing your cameras. As a general rule (again whether this is law is not something I am getting into here), angle them to include nothing other than your private premises, even if that means having what might be unusual angles. I have read about some people fitting cameras that also pointed towards the bathroom of a neighbour only a few metres away. That’s totally unreasonable.
THE CLASSIC MARKETING PLOYS
FRAME RATES – Oddly, the CCTV industry advertise frame rate as the rate the system can capture. It’s the strangest and most meaningless thing to me from a camera background. What this means is that a system may have 100fps on the box (a nice big number you might note). This means 4 cameras each doing 25fps.
IS FHD REALLY NECESSARY? – Remember that high resolutions are just not always necessary or practical. 4K video is still incredibly data heavy. Don’t bother with it. Not for CCTV. 720p is fine in most cases. It’s all back to the old digital camera megapixel ploy. Higher is not better unless the processing, optics and sensor is there to back it up. On a £400 CCTV system, it is not.
FRAME RATE AT FHD – Many systems may capture e.g. FHD (1920×1080) but it will more often than not be at a reduced frame rate. Watch out for that as it could get down to 5fps on cheaper systems.
RESOLUTION – A FHD system with 8 camera inputs will almost certainly not be able to capture full HD on more than e.g. 4. The rest will be the much lower CIF or D1 resolutions.
I’m not stating this as fact. You may have a reason that you believe 25 images per second will be required. That’s up to you but I don’t believe it’s needed in most installations.
The only exception to the frame rate argument could be around shutter speed. If your camera is able to capture at 12fps, it can also use a shutter speed as low as 1/12 sec. I would never take a photo at that kind of shutter speed if someone was moving. The image would not be usable.
The same applies for video. Pushing the frame rate up will most likely force a higher minimum shutter speed. This will give you a higher hit rate on images but 1/25 sec is still way too low for motion without blur and you’ve lost a whole stop of light which needs to be compensated for in gain which = noise = lower image quality anyway.
I know from using cameras that even when someone is moving, there are always moments at the apex of a movement where motion stops. At 15fps, you should get what you need. And remember, going back to point 2, these systems are not spectacular. They have limitations and positive id may be one of them. Deterrence in the name of the game here.
QUALITY CABLES & CABLE LENGTH
WIRED VS. WIRELESS CCTV
CBR VS. VBR & QUALITY SETTINGS
Let’s just briefly explain a bit about video compression and the difference between variable bitrate (VBR) and constant bitrate (CBR). Compressing video is based largely on motion. If nothing happens in part of a scene, it doesn’t need to be stored again and again on each frame. If the whole frame changes all the time (if a burglar was stood jumping up and down right in front of your camera) your video would need more data, or more bits, to record it nicely.
This is where bitrate comes in. Constant bitrate is simple. If you set your recorder to record at 2048kbps, it will do exactly that…all the time. You will be writing 2048 kilobits, or 256 kilobytes (2048 divided by 8) per second to your hard drive for that camera. If nothing’s happening, you’re probably wasting a bit of data. If a lot happens, you might not be feeding it enough. Variable bitrate is much more complicated technically but also simple to explain. With VBR, the complexity of a scene is constantly monitored and the bitrate is pushed up when something is going on and allowed to drop back when nothing’s happening. There are minimums and maximums within this. In fact, the Quality setting on VBR will, among other things, set the lowest and highest amount of data you can capture per second. Overall, VBR is the best solution for CCTV image quality. CBR is only really essential if you are limited on space or need to be able to perfectly predict how many days of video you need to store.
So back to the tip. 2 of my scenes contain large trees. The problem with trees is that when they move, the random motion of the leaves is very hard to compress. If have set these 2 cameras to ‘Best’ quality so, when required, they can still record activity clearly together with the moving content of the trees. The other 2 look onto areas with no motion 90% of the time. These are set to the lower ‘Good’ setting. Anything that does happen does not have to compete with a tree for bits and it saves me over 1GB of data per hour!
Now, how this fits for your scenes I can’t say and you might just want to max everything out. However, understanding what’s going on might help if you’re pushed for space on the hard drive.
So there we are. 9 tips to help you choose and setup your CCTV system. I’m totally new to CCTV but not at all new to cameras and video. I hope this has been useful to you and thanks for visiting. Please check out my YouTube channel for more content like this.