As megapixel surveillance cameras become mainstream, many have begun questioning the value of PTZs. The main criticism of PTZs is that they can only provide good image quality by 'looking' at a very small area at any given time. Megapixel cameras, on the other hand, can see 'everywhere' at all times. With their significantly increased resolution, operators can simply digitally zoom to magnify any area of interest. With this approach, the megapixel camera provides the best of both worlds - capturing details at a distance while recording video across large areas.
But how true is this really? What drawbacks does a MP camera have compared to a PTZ and in what scenarios?
In this report, we share our test results of a shootout between a PTZ camera and 4 megapixel cameras (ranging from 720p to 5MP from Axis, IQinVision, Sony and StarDot). We wanted to see what tradeoffs would be revealed if we tested these cameras at the same time and in the same space.
We took our 5 camera test rig and set up at a moderately sized public parking lot. See the test location below:
We then set up a series of tests (during the day, twilight and nighttime) where a subject would move across the covered area. We tracked the subject with our PTZ camera and then contrasted the PTZ's resulting image with that of the megapixel cameras. The overview image below shows the dimensions of the test area and the key testing points we selected:
We then conducted competitive analysis for various scenes to rate and compare the relative performance of each camera. Here are the 15 scenarios we analyzed:
- PTZ Capture Area vs MP Capture Area
- Daytime Comparison by Distance / HFoV - 5MP vs PTZ
- Nighttime Comparison by Distance / HFoV - 5MP vs PTZ
- Midday Even Lighting (Far Subject)
- Midday Even Lighting (Mid Subject)
- Midday Even Lighting (Near Subject)
- Twilight Harsh Lighting (Far Subject)
- Twilight Harsh Lighting (Mid Subject)
- Twilight Harsh Lighting (Near Subject)
- Nighttime Lighting (Far Subject)
- Nighttime Lighting (Mid Subject)
- Nighttime Lighting (Near Subject)
- Daytime License Plate Capture (Far Subject)
- Daytime License Plate Capture (Near Subject)
- Nighttime License Plate Capture
We found the results, and especially the tradeoffs, to be fascinating.
Readers of this report should understand the fundamentals of PTZ cameras and megapixel cameras. For background, review our training on PTZ Camera fundamentals and our megapixel camera shootout at this same parking lot.