Lux Ratings are Subjective!
Lux Ratings are Subjective!
Lux - where everything is made up and the points don't matter.
Lux Ratings tell you how a brand thinks about their lineup of cameras, but you can't compare Lux from brand to brand.
What is Lux Rating measuring?
Lux is measuring the wrong thing.
Lux is a measurement of incident light, or the light that is falling on the object. On the other hand, your IP security camera sees and records reflected light, which is light that bounces off the object and makes its way to the camera lens. Some objects and certain colors reflect light differently. This means that even if you can accurately measure the amount of lux hitting an object, you are going to have a lot of viability with the amount of lux reflecting off the object and into the camera's lens.
Also, since all we can measure is the light hitting an object - not the light reflecting off the object - measurements of lux in the atmosphere are pretty worthless. Two scenarios with the same lux rating, can produce different results because atmospheric differences, like bugs, humidity, fog, and other weather can how much of the light reflected off an object ends up hitting the camera image sensor.
Even with the level of atmospheric lux, differences in humidity, fog, rain, or many other things can change how good the picture looks.
Lux Ratings are Subjective
If you are in the industry, we can't recommend a subscription to IPVM more highly, but if you just a regular one-time shopper looking to make a wise decision, we've summarized this great guide by IPVM on why lux ratings aren’t reliable specs from Brand A to Brand B.
1. Unrealistic numbers
Lux is difficult to measure and the process of measuring lux isn’t very reliable or repeatable. Two people can measure the same environment and get different lux ratings. Air humidity, color and shape of what you are filming, for example, has a huge effect on how much light reflects off of an object. Lux ratings measure the light on an object, not the light reflecting off the object (which is what the camera records).
2. No standard process
Each manufacturer measures lux on their own with their own process.
3. No images in low light
Everyone uses different measures of success, is that grainy low-light image good enough? Hard to tell since no one publishes the image at that lux rating, and even if they did humidity can radically alter the results.
4. Failure to disclose camera settings
Slowing the shutter speed down allows more light into the sensor, which lets you take a color photo at low light levels at the cost of motion blur. Without a frame rate and shutter speed standardization, you can’t compare apples to apples.
5. Gradual image quality decline
Low light always reduces the quality of an image. Increasing gain control can result in greying and signal noise and slowing the frame rate increases motion blur, so what constitutes success? There’s no standardized quality level for what counts: “can you actually identify someone?”
This creates an ugly system where even the most ethical and responsible manufacturers are trapped...
Worse, it rewards the most unscrupulous vendors who realize that they are rarely, if ever, called on their specs.
So, let us tell you the truth. Lux rating, if it means anything at all, just tells you the subjective opinion of what the manufacturer thinks is an acceptable image.
Wait. Your cameras have lux ratings. If it is such a terrible spec, why even include it?
Because there's no standards in measuring lux or even a standard definitions of success in low light imagery, you should have absolutely zero confidence that Brand A's 0.01 lux camera is actually better than Brand B's 0.02 lux camera. But that also doesn't mean that Lux is 100% useless.
A subjective opinion is better than nothing.
Yes, there's massive challenges in standardizing the measurement of lux, but most brands do remain largely consistent in their testing environments and testing methodology when comparing their products to each other!
You can be 100% confident that Brand A's 0.001 lux camera is indeed better than Brand A's 0.1 lux camera.