Dispelling more megapixel myths

Three new myths bite the dust


Despite a decade of nay saying and multiple players coming and going, megapixel technology is now mainstream. However, only a few of the megapixel players appear to be investing in the product development, support and quality control required for long-term success. Further, even as megapixel has gone mainstream, misunderstandings and misinformation continue to hamper a clear understanding of this technology’s powerful potential.

The Pre-Megapixel Era of Equality is Over

Today, there are a number of megapixel network camera manufacturers who would have end-users believe that all cameras are created equal — and if you believe that, I have some outstanding beachfront property for you in Death Valley. The truth is, not all megapixel cameras are created equal, and that makes it difficult to figure out which camera is right for you. The Pre-Megapixel (CCTV) Era was much easier — you designed the system around the DVR since all cameras were, truly, pretty much the same. Whether you bought your CCTV camera from company X or company Y, you were more than likely getting a camera that used the identical system on chip imager made by company Z.

In the IP video space, things are quite a bit different, and more often than not, integrators and designers are now building their systems around the cameras, not the recording device. In the Pre-Megapixel Era, it was easy because you knew that if you wanted to recognize a face or read a license plate (forensic detail); you could only cover a 16-foot-wide area, regardless of what camera you used. So in the good old days, you chose the cheapest camera that you knew to be reliable. In modern times, camera resolutions vary considerably, so selecting the right camera requires a bit more thought because you do not want to buy a camera that has too much or too little resolution for your application.

As megapixel technology is increasingly among the range of choices for most end-users, it is important to clear up some of the more prominent misunderstanding or myths out there today. Here are three of the more common pieces of misinformation about megapixel cameras:

Megapixel Myth #1: When Megapixel isn’t Megapixel

So what are the differences between today’s cameras? There are a number of factors to consider. First, from a specification sheet perspective, we look at a camera’s resolution. Cameras today can vary from VGA to tens of megapixels, so one megapixel camera is not the same as the other. Some manufacturers have gone so far as to call a VGA camera a 0.3 megapixel camera. That’s a bit like calling your little kitty a lion — it’s not even close.

Let’s say you need to cover an area 64 feet wide by 48 feet deep at a forensic level of detail (40 pixels-per-foot). Taking some liberties to simplify this example (lenses don’t actually deliver a square field of view), you would need 64 x 40 pixels wide (=2560) by 48 x 40 pixels deep (=1920) or a total of 4,915,200 pixels (2560 x 1920). If you use a 0.3 “megapixel camera” (translation: VGA camera at 640 x 480), you would need 16 of them to cover the desired space. If you use a 5-megapixel camera, one will do the job (see the graphic above).

Now let’s calculate costs. If you choose a VGA camera that costs about $200, you will pay 16 x $200 = $3200. Divide the cost by the total number of pixels and you come up with $0.00065/pixel. Alternatively, if you select a high-end, reliable 5MP camera that costs about $1200, using the same calculation, we find your cost would be $0.00024/pixel which is 63-percent cheaper — and that’s before you consider installation costs like cabling, power and housings! What’s the point? Just because a company may use the term megapixel in its marketing does not make it a megapixel camera.

Megapixel Myth #2: HD the Next Megapixel?

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