National Instruments NI 17xx Manual De Usuario

can be used to calculate the maximum exposure. Assuming the object is 
moving horizontally across the field of view, use Equation 5-1 to calculate 
the maximum exposure time.

(5-1)

where

 is the maximum exposure time without blurring,

R is the rate of motion of the object either horizontally or 
vertically,

FOV is the field of view in the direction of motion, and

N is the number of sensor pixels in the direction of motion

For many applications that include moving objects, additional lighting is 
necessary to achieve good image contrast due to the short exposure time 
required to avoid motion blur.

Additionally, in many environments, the ambient light conditions vary too 
significantly to obtain consistent results without adding dedicated lighting. 
For example, in a building with windows, the ambient light can vary 
significantly with weather. Also, standard fluorescent lighting flickers at a 
rate that is perceivable by the smart camera. In these situations, the ambient 
light must be overridden with a dedicated light source to ensure 
reproducible results.

You can configure the NI Smart Camera to acquire images based on 
internal timing or an external trigger signal. In both cases, the smart camera 
can acquire full frame images at the camera’s maximum frame rate. 
If partial scanning or binning are enabled, the smart camera can acquire 
images faster than the full frame maximum frame rate. Refer to the 

 section for information about factors that affect the 

maximum frame rate.

The NI Smart Camera features two types of internally-timed modes: 
free-run mode and fixed-frame-rate mode.

In free-run mode, the smart camera acquires images at the maximum frame 
rate allowed by the configuration.

2

×

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