Key Specs That Matter When Selecting an Industrial Imaging Camera

Selecting the right industrial imaging camera is often the difference between success and failure in your operation.

Select the wrong one and you’re dealing with a camera that produces blurry and indiscernible images, potentially missing defects that can cost you money. Select the right one and you can experience a whole new level of precision that you may not have thought possible in your production line.

The problem, of course, is that…

The industrial camera market is projected to reach $3.61 billion by 2033. This growth has and is resulting in hundreds of options flooding the market at any given time. But, of course, not all cameras are created equal.

In fact, to help you out, in the remainder of this article, you’ll find the key specs that matter when selecting an industrial imaging camera.

Key Specs That Matter When Selecting an Industrial Imaging Camera

• Why Camera Specs Matter More Than You Think
• Resolution: The Foundation of Image Quality
• Frame Rate: Speed That Counts
• Sensor Type: CMOS vs CCD Explained
• Interface Standards: Getting Your Data Where It Needs To Go
• Other Critical Specs To Consider

Why Camera Specs Matter More Than You Think

Industrial imaging cameras power everything from defect detection to robotic guidance systems in a variety of different industries.

Their prevalence and use have only increased as machine vision systems achieving up to 99% accuracy in defect detection become more common. After all, choosing the right high-performance industrial cameras is not something to be taken lightly.

Camera specifications determine whether or not the imaging camera you have selected can handle the environment it is working in and, in turn, determine whether or not you’ll be able to catch defects that matter most to your bottom line.

Let’s use a simple example to highlight this further:

• A camera with the wrong resolution will not be able to capture fine details that may be the target of defect detection.
• A camera with a low frame rate will not be able to inspect fast-moving products.
• A camera with the wrong interface will be a bottleneck in your data pipeline.

Pretty critical elements, right?

To help you out further, we’re going to break down each spec to highlight exactly what to look out for.

Resolution: The Foundation of Image Quality

Resolution is often the first specification that people jump to and, while there’s a reason for that, it’s still best to understand it first.

Resolution determines how much detail an industrial camera can capture, measured in megapixels (MP). Resolution directly affects a camera’s ability to detect small defects and measure the components that are being inspected.

The higher the resolution, the more pixels will be captured and the finer the details that will be available in your image. However, what people often fail to realise is that higher resolution isn’t always better.

More pixels translate to larger file sizes which, in turn, take a longer time to process. A longer time to process leads to a slower inspection system if your processing hardware can’t keep up.

Resolution should be matched to the application:

• Low resolution (1-2 MP) for presence detection and simple positioning
• Medium resolution (2-5 MP) for general inspection and barcode reading
• High resolution (5+ MP) for detailed surface inspection and precision measurement

Take a look at the smallest defect that you need to detect and then work backwards to determine the resolution you need.

Frame Rate: Speed That Counts

Frame rate is the measurement of how many images a camera can capture in one second.

This specification comes into play when products are being inspected on a fast-moving production line, as if your camera can’t keep up with the line speed, then defects will be missed.

Frame rate is measured in frames per second (fps) and most industrial cameras range between 30fps to several hundred fps.

To further help you out, you should calculate how fast products are moving through your field of view and then ensure that your camera can capture enough frames to inspect each product.

A higher frame rate usually means a lower resolution as most cameras force you to make a tradeoff between speed and detail.

So, as always, you have to find the right balance for the application that you have in mind.

Sensor Type: CMOS vs CCD Explained

We’ll level with you, the sensor is the heart and soul of any industrial camera.

There are two main types of sensors on the market, CMOS and CCD, each with their own advantages and disadvantages.

CMOS Sensors:

CMOS sensors are currently the industry standard for most applications due to their lower power consumption, faster readout speeds and easier integration options. In recent years, CMOS sensors have caught up with CCD in terms of image quality.

CCD Sensors:

CCD sensors are still the go-to option in some applications that require the highest possible image quality. CCD cameras typically provide better light sensitivity and lower noise but at the cost of more power and a higher price tag.

For most industrial applications, CMOS sensors are the way to go today. But, if you are operating in low-light conditions or require absolute top image quality, CCD sensors might still be the right choice.

Interface Standards: Getting Your Data Where It Needs To Go

You need your camera to be able to communicate with your processing system in some way. The interface determines how fast your image data will move from the camera and over to your computer. Select the wrong interface and you’ll create a bottleneck that’ll slow everything down.

The main interface standards you’re going to come across are:

• GigE Vision: Standard ethernet cables are used and this option provides for long cable runs up to 100 meters. GigE Vision is great for distributed systems.
• USB3 Vision: Offers high bandwidth and is easily integrated with standard PCs. Cable lengths are, however, limited to around 5 meters.
• Camera Link: This is a traditional high-speed interface for more demanding applications. Requires specialised frame grabbers.
• CoaXPress: Delivers extremely high bandwidth over coaxial cables and is ideal for high-resolution and high-speed applications.

Match your interface to your system requirements based on cable length, bandwidth requirements and existing infrastructure.

Other Critical Specs To Consider

Beyond our big four, there are some other specs you should consider.

Dynamic Range:

The dynamic range of a camera measures how well it is able to capture detail in both dark and bright areas simultaneously. The higher the dynamic range, the better a camera can perform in challenging lighting situations.

Pixel Size:

Pixel size is also an important spec to consider as larger pixels will capture more light and result in better low-light performance. Conversely, smaller pixels mean that a higher resolution can be crammed into a smaller sensor.

Global vs Rolling Shutter:

Global shutter captures an entire image at the same time while rolling shutter captures an image line by line. The former is ideal for fast-moving objects as it will prevent distortions.

Operating Temperature:

Industrial environments can be harsh and it’s important to ensure that your camera can handle the extremes of your application temperature-wise.

Pulling It All Together

As you can probably tell, selecting the right industrial imaging camera comes down to fully understanding your application requirements.

You should start by defining the components that need to be inspected or the products that need to be monitored and from there, you should consider the size of the defects that need to be detected and the required inspection speed.

Only when you have a clear picture of your requirements should you go about matching these to camera specifications like:

• Resolution for detail
• Frame rate for speed
• Sensor type for image quality
• Interface for data transfer

As always, don’t go chasing the highest specs across the board. Instead, you should find the balance that provides results for your specific application.

The best camera is not necessarily the most expensive. Instead, it’s the one that can solve your problem in the most reliable way possible.

Defining your requirements is essential and you should also test out cameras in your environment to know for certain if they are ideal.