Is There Ever Enough Resolution?By: Brian Rhodes, Published on Feb 20, 2014
The megapixel 'race' is over. Or it is not.
Not only is this an ongoing debate among manufacturers, it is a key decision among specifiers and users.
Now, as the alarm industry finally turns towards modernity IP, they offer an amazing recommendation.
In the security market, ESX [link no longer available] has long catered to the alarm dealer crowd. Their annual tradeshow is a flagstone event where 'old guard' alarm dealers crash together with the newest technology. Indeed, the old literally meets the new at this event, and so marketing takes an easy-to-understand tone for inexperienced installers.
The mail below is a prime example of this, which positions resolution against the assumption readers are clueless by claiming 'Enough is Never Enough [link no longer available]' when it comes to megapixels:
At best, this premise is inaccurate, and at worst it all but guarantees that alarm dealers who take it to heart will cause major problems. In the sections that follow, we examine the major claims of the piece and follow up with why they are just plain wrong.
Hype vs. Truth
In a fluff piece full of factually arguable claims, four rise to the top:
- "HD surveillance provides exceptional clarity, resolution and detail to ensure all available evidence is captured in daytime and nighttime settings"
- "Cameras with higher resolutions provide more detail..."
- "Bottom line is higher resolutions result in better business decisions and faster, more accurate apprehensions."
- "So, how much is too much resolution? It doesn’t look like there’s ever enough."
Lets take at look at where each claim falls short.
HD is No Guarantee of Anything: Despite the claim of 'exceptional clarity' and 'detail', resolution alone does not ensure capture and details regardless of day or night. Indeed, many HD cameras are utter garbage at night, with features like Day/Night, Compression settings, WDR, and Integrated IR or Super-Low Light also playing a key role in how well the camera performs.
Light Trumps Resolution for seeing Details: Here is a counterclaim: cameras with great light will outperform the same cameras in bad light. It simply does not matter how many pixels your camera brings to bear if scene lighting does not support it. Time after time, our tests demonstrate lack of light will kill details that could otherwise be seen if light was sufficient:
PPF matters first, Resolution Follows: Do your customers need to pay for a higher resolution, when something lower will do just fine? According to ESX's guidance, that key question never is asked. When it comes to basics, resolution should not be the tail that wags the dog. Indeed, one of the precepts of our IPVMU IP Cameras Class is summed up by the slide below:
(For more details, see our Definitive Guide to PPF)
The composite image shows three PPFs (L-to-R: 40, 60, 80ppf) and the fact is driven home: Why/how exactly is the 80ppf more useful than the 40 ppf image? While the debate about image quality can be made, it could simply be dismissed as frivolity when every important detail can be seen at lower resolution. How much PPF is actually needed in the scene, and the corresponding question of resolution, is a function of design first, not blind specification.
Too much Resolution can kill you: While camera marketers would love for nothing more than to sell you increasingly greater (more expensive) resolutions, looking only at the camera ignores much of the problem. Higher resolution (especially beyond 3MP) brings far higher storage costs, lower frame rate capabilities, worse low light performance and crippled WDR.
An inexperienced dealer who takes ESX's advice and bids the highest resolution solution available is going to be destroyed by the design that applies the right resolution. A properly designed system will deliver superior image quality for less money that one simply specifying the most resolution out there.