What is a Megapixel Camera?
CCTV Equipment Software and Systems
Megapixel Cameras are now becoming readily available and at an affordable price. Our Camsecure IP Megapixel HD cameras are a prime
example of this new technology.
So what does megapixel camera mean?
Megapixel means one million pixels. The resolution of digital cameras and camera phones is often measured in megapixels. For example, a
two-megapixel camera can produce images with two million pixels.
Since pixels are usually square and form a grid, a 1-megapixel camera will produce an image roughly 1200 pixels wide by 900 pixels high.
By comparison, a VGA image (640 x 480 pixels) would be only 0.3 megapixel.
The picture quality advantages of megapixel network cameras are of benefit in a couple of ways. In some applications, a megapixel network
camera could cover the same area as a CCTV camera with an improved level of picture quality so you could actually identify people. We are
all too familiar with images captured by CCTVsystems where the quality was so poor little could be learned and often no positive identification
possible. Megapixel network cameras solved this major disadvantage.
For other applications, megapixel meant covering a much wider area than CCTVcameras. Comparing apples-to-apples, a one megapixel
network camera can cover more than four times the area of a CCTVcamera with the same resolution. This means you can replace four
CCTVcameras with a single megapixel camera, or 10 CCTVcameras with one 3.1 megapixel camera. End-users embraced this new power
and efficiency immediately and the migration from CCTVto megapixel network cameras has predictably accelerated.
With no legitimate way to combat loss of market share and still remain profitable, some began misrepresenting megapixel cameras to
discourage the rapid migration away from their technology.
Do you know the real story?
True or False? Megapixel network cameras can be less costly than CCTVcameras.
TRUE! There have been misrepresentations that megapixel network cameras cost more than CCTVcameras. The initial cost of a professional
quality megapixel network camera may be higher than a CCTVcamera. However, in a large majority of applications, the total cost of installing
a system using megapixel network cameras is substantially lower, sometimes as much as 50% lower.
If you are considering using a megapixel network camera as a one-for-one replacement of a CCTVcamera, and there is no established
IPnetwork, megapixel may be more expensive than CCTV. But the only reason to even consider swapping one-for-one is because the
CCTVcamera cannot deliver the image quality you need. Put another way, a tricycle is indeed cheaper than a Ferrari, but if you need to go
200 mph, try doing it on that nice cheap tricycle.
True or False? Megapixel network cameras use more bandwidth and storage than CCTVcameras.
FALSE! Of course megapixel images are larger than CCTVimages, but once again this is not an accurate or helpful comparison. If you want
to replace CCTV cameras one-for-one with megapixel cameras, it is because the CCTVcamera cannot deliver the image quality you demand,
period! A more instructive and fair analysis is to compare the files sizes of four 704 x 480 CCTVcameras against a single 1280 x 1024
megapixel image. If all cameras are configured the same, with the same compression, and are looking at the same scene at the same time
you will find that a megapixel network camera actually uses less bandwidth and storage than the CCTV cameras combined.
True or false? A CCTVcamera with a good zoom lens will deliver the same level of detail you get from a megapixel camera.
FALSE! There is no delicate way to state it: this statement is absolutely, unequivocally false, false, false, false, false!
The area you can cover with reasonable detail (enough to recognize a face or license plate) does not depend on the lens, it depends on the number of pixels covering the
scene. The best CCTVcameras have, at most, 704 x 480 pixels. As a general rule, 30 pixels/foot lets you recognize a face or read a license plate. So, the best CCTV
camera can cover an area 23 feet wide (704/30) and 16 feet high (640/30), for a total of 368 ft2. Knowing that, you would need to select a lens that gives you, at most, a 23'
wide field of view to get enough detail. Putting a wider lens on the camera will simply blur the image and putting a telephoto lens on the camera will get you a sharper
picture but a much smaller coverage area.
Alternatively, a 1280 x 1024 megapixel camera lets you cover a 43' x 34' area or 1462 ft2(4x the coverage of the CCTVcamera). A3.1 megapixel camera, at 2048 x 1536,
can cover 3450 ft2, or almost 10x the coverage of the CCTVcamera. The lens simply determines how far away you want that level of detail. Awide angle lens can get the
detail very close to the camera and a telephoto lens can get the detail at a great distance from the camera, but neither gets you megapixel quality and area of coverage.
We've covered three very prevalent misrepresentations about megapixel technology that have clouded decision-making and prevented end-users from understanding
megapixel's potential and cost-effectiveness. The best way to judge for yourself is to see it for yourself, compare a megapixel camera to the others, and then you will see
the real picture.