SQM-LU-DL
Unihedron
From ~$326.60
3 stores
The Unihedron SQM-LU-DL is a USB-enabled data-logging light meter that measures night sky brightness in magnitudes per square arcsecond for astronomers and light pollution researchers. Featuring an infrared blocking filter to restrict measurements to the visual bandpass and a narrow field of view of approximately 20 degrees, it provides precise readings at even the darkest sites. The meter supports continuous autonomous data logging via USB, external battery power, or mains-powered operation, making it ideal for quantifying light pollution trends, correlating sky brightness with observing conditions, and long-term sky monitoring campaigns.
Astronomy Plus
Sky Quality Meter - LU-DL (SQM-LU-DL)
Worldwide shipping
CA$450.00
~$326.60
First Light Optics
Unihedron SQM-LU-DL Sky Quality Meter with USB and Data Logging
Worldwide shipping
£279.00
~$377.32
Astroshop.eu
Photometer SQM sky quality meter with lens, USB and data logger
Worldwide shipping
€339.00
~$399.10
Specifications
| Field of View (FWHM) | 20° |
| USB Cable Length | 15 ft |
| Battery Cells Included | 6 |
| Recording Memory Capacity | 1048576 |
| Maximum Light Sampling Time | 80 s |
| Field of View (HWHM) | 10° |
| Case Dimensions | 5.5 in |
| Power Supply | 5 V |
| Data Logging Capability | ✓ |
| Minimum Light Sampling Time | 1 s |
| Field Upgradeable Firmware | ✓ |
| Infrared Blocking Filter | ✓ |