Manuel Spitschan. Photo credit: Verena Müller.
An international study involving 191 adults across nine sites, totaling 1,480 participant-days and more than 400 natural indoor and outdoor scenes, represents the research team’s largest real-world light-exposure cohort to date
The light in a laboratory is not the light of real life. It doesn’t shift with the seasons, follow you outdoors, or change as you move from a sunlit street into a dim office. For years, that gap has limited what researchers can learn about how light truly shapes our circadian rhythms, sleep and visual health.
For Manuel Spitschan, Assistant Professor of Chronobiology and Health at the Technical University of Munich and Research Group Leader at the Max Planck Institute for Biological Cybernetics, this was one of the reasons he turned to Condor Instruments.
Spitschan first became aware of Condor when he was a postdoctoral researcher looking for wearable actimeters and light loggers that combined scientific capabilities with affordability within a relatively small research budget.
“We wanted instruments that would allow us to move beyond small laboratory studies and measure light exposure and activity in everyday life, including in larger cohorts,” he says. “Condor offered a combination of research-grade measurements, wearability and affordability that made this possible.”
Measuring light in real-world conditions
According to Spitschan, one of the greatest differentiators of Condor’s solution is the quality of light measurement in a wearable device, particularly its ability to quantify melanopic EDI and recover meaningful spectral information alongside activity measurements.
This is particularly valuable for circadian and sleep research, where conventional illuminance alone does not capture the biologically relevant characteristics of light exposure.
Using Condor devices, Spitschan’s research team was able to conduct an international field study involving 191 participants, making it their largest real-world light-exposure cohort to date [1].
The team has also performed dedicated field-validation work comparing the devices against laboratory-grade spectral reference instruments across more than 400 natural indoor and outdoor scenes [2].
The devices showed very high agreement with the reference measurements. The validation also allowed the researchers to characterize and quantify systematic measurement biases under different lighting conditions.
“This gives us considerable confidence in the quality of the data we collect and, importantly, a much better understanding of how the instruments perform in real-world research settings,” Spitschan says.
Beyond the devices: a scientific partnership
For Spitschan, the experience with Condor Instruments goes beyond the performance of the devices themselves. The relationship with the people behind the instruments has also been an important part of the collaboration.
“The people behind the instruments are also an important part of the experience,” he says. “The Condor team is approachable, responsive and genuinely interested in the science being done with their devices.”
He adds that the Condor team cares about how the instruments perform in real studies and is open to discussing scientific and methodological questions. “That relationship has been very valuable to us as researchers.”
References: [1] https://doi.org/10.64898/2026.06.04.730226 and [2] https://doi.org/10.48550/arXiv.2606.20719
