What are Shutter Speed and Exposure Time?

The exposure time determines the interval during which the sensor collects light data. In machine vision, this translates into how much detail is preserved and how clearly a moving object appears.

If the exposure time is too long relative to how fast an object moves or if the object shifts position on the sensor during exposure, this can create blur across multiple pixels. This pixel displacement is known as pixel blur, and it can distort edges or shift measurements.

Even a single-pixel shift can disrupt algorithms for applications focused on dimensional accuracy or flaw detection. Exposure time is the calibration point that determines the difference between passable and precise. Slower inspections with static objects may tolerate some blur, while high-speed assembly lines require strict timing.

Fast shutter speeds and short exposure times are key when inspecting moving parts because they help "freeze" motion and avoid distortion. This is particularly helpful for reading barcodes, verifying labels, or detecting features on rapidly moving assemblies.

Slower shutter speeds are better suited for low-light conditions or static targets; allowing more light to reach the sensor helps brighten underexposed images. However, a more prolonged exposure introduces more room for error when objects move. In these situations, lighting must be adjusted to avoid blur. Shutter time varies depending on the task, and understanding how that timing shifts work is key to keeping inspections clear and consistent. Applications focused on surface flaw detection, for instance, may prioritize detail even at slower speeds, while part positioning systems favor speed to keep up with line throughput.

Lighting and exposure work in tandem. As the shutter speed increases, less light hits the sensor; to compensate, systems often increase illumination or widen the aperture. But opening the aperture too far reduces depth of field, making it harder to keep the entire object in focus. This is especially important when inspecting objects with curved surfaces or varying heights, where consistent sharpness is required.

This balance becomes especially important on high-speed lines as a fast shutter with limited lighting can produce underexposed or noisy images; slowing the shutter may help capture more light, but increases the risk of motion blur. Finding the right balance includes coordinating lighting, lens aperture, and exposure time.

In high-speed environments (like packaging lines or surface inspections on conveyor belts), accurate imaging depends on whether the camera can freeze motion clearly. When parts move during the exposure window, even slightly, they can blur across multiple pixels, making it harder to detect features, measure dimensions, or identify defects.

Many vision systems have built-in exposure control and fast global shutter technology that allows cameras to capture high-speed motion without distortion. Then, when paired with precise lighting and synchronized timing, they reduce the need for manual calculations or trial-and-error adjustments. Whether the goal is to read fine details on a fast conveyor or to capture consistent images in ever-changing conditions, optimized shutter speed settings help deliver reliable results.

There’s no one-size-fits-all exposure time; it has to be tuned to match the application. The first step is to identify the minimum feature size that needs to be detected and the maximum speed at which the object travels. From there, calculate the exposure time needed to prevent more than 1/10 of that feature from shifting during capture. For example, if a component moves at 1 meter per second and the smallest feature is 100 microns, exposure time should be no more than 10 milliseconds.

Changing the shutter speed also affects how much light the sensor receives and how much of the object stays in focus. Faster settings reduce light intake, which means the system needs either stronger illumination or a sensor with higher sensitivity. Pushing gain too far can introduce electronic noise; it’s better to adjust shutter speed, aperture, and lighting as a group. That way, the camera produces stable and clean images without having to compromise on image quality.

Tools like programmable region-of-interest (ROI) settings and built-in exposure control allow for faster configuration and more precise capture across variable scenes.