Lighting technology (luminotechnology) is a field in constant evolution that combines technology with aesthetics. However, in this quest for lighting perfection, we often encounter challenges such as the stroboscopic effect, a phenomenon that can cause visual discomfort and affect the perception of light. We help you solve it!
In this article, we will explore what the stroboscopic effect is, what can cause it, its relation to flicker or light flicker, and how to avoid it.
What Is the Stroboscopic Effect?
The stroboscopic effect is the optical effect where objects appear to move at a slower speed than reality. This occurs when an object in motion is illuminated periodically with bursts of light.
This perception is due to the fact that the human eye or camera captures only a limited number of images per second, and if the light source flickers at the same frequency (hertz or Hz), it can make moving objects appear static or exhibit the stroboscopic effect. In the context of lighting technology, this means that the speed at which a light source turns on and off must be high enough for the human eye not to detect the flicker.
For example, if a light source flickers at a frequency of 60 Hz (60 times per second) and a camera records at 60 frames per second, the camera will capture every change in light intensity at the same point of the light source's oscillation.
The stroboscopic effect is not always unwanted: a very recognizable example occurs with flashing lights used in festive events, where a sensation of slow and distorted movement is perceived.
How to Avoid the Stroboscopic Effect?
To avoid the stroboscopic effect, it is essential to provide continuous and stable lighting. To ensure this, you can follow these steps:
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Selection of Suitable Lighting Fixtures
Opt for lighting fixtures specifically designed for high-speed image capture or video recording applications, designed to minimize fluctuations in light intensity and maintain constant light without the stroboscopic effect.
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Use of Light Dimmers
Use high-quality light dimmers (dimmers) that maintain consistent lighting even during intensity variations. Avoid low-cost light dimmers that may introduce unwanted flicker.
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Current Stabilization
Use stable power supply systems or stabilized drivers to prevent fluctuations in the electric current frequency, contributing to more consistent lighting.
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Frequency Synchronization
Ensure that the flicker frequency of light sources is synchronized with the frequency of the supplied electric current (such as 50 Hz or 60 Hz, depending on the region). This is achieved by using ballasts or suitable electronic controllers that generate stable high-frequency current, eliminating any perceptible variation in light intensity.
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Measurement and Testing
Use specialized measuring tools and testing equipment to verify light quality and the absence of flicker. Oscilloscopes and spectrophotometers can help detect imperceptible fluctuations in light intensity.
What Can Cause the Stroboscopic Effect?
The stroboscopic effect can be triggered for various reasons, with one of the most common being incompatibility between the frequency of the light source and the speed of the camera or human eye. For example, when recording videos or using artificial lighting in sports events, if the frequency of LED light flickers in an unsynchronized pattern with the camera's speed, the stroboscopic effect can appear in the recording.
Another cause is variability in the frequency of the electric current supplied to the lighting fixtures. For instance, in places where alternating current (AC) operates at 60 Hz, using a light source that flickers at a different frequency can cause the stroboscopic effect.
Do you need help with your lighting project? Contact us and we will be happy to help you.
