About this product
Part Number: SQM-LU-DL-V
A USB enabled vector data-logging light meter for night-time sky brightness monitoring!
An affordable meter for continual, connected or autonomous data-logging to measure sky brightness for astronomers and light pollution investigators.
The "Sky Quality Meter - LU-DL-V" (SQM-LU-DL-V) measures the brightness of the night sky in magnitudes per square arcsecond.
Designed by Dr. Doug Welch and Anthony Tekatch
- Measuring the night sky brightness during remote biological field experiments.
- Find out how good the night or site REALLY is.
- Compare the sky brightness at different sites quantitatively.
- Document the evolution of light pollution in your area.
- Set planetarium dome illumination to mimic the skies people are likely to experience elsewhere in the city.
- Monitor sky brightness through the night, night-to-night, and year-to-year.
- Determine which nights show the greatest promise for finding the 'faintest fuzzies'!
- Calibrate the effect of sky brightness on qualitative measures such as the Bortle Scale.
- Investigate how sky brightness correlates with the solar cycle and month-to-month sunspot activity.
- Help provide local ground truth for future sky brightness prediction with the Clear Sky Clock.
- CCD users can make a correlation between the SQM reading and when the background reaches some ADC level.
- Sky brightness reported in visual magnitudes per square arcsecond.
- Infrared blocking filter restricts measurement to visual bandpass.
- Sensor temperature, model number, and serial number are provided.
- Precision readings at even the darkest sites.
- Field-upgradeable firmware.
- All the features of our SQM-LU (USB model) plus Data logging capabilities and vector measurements.
- Open protocol and product manual..
- USB connectivity
- Data-logging capabilities while operated from external battery.
- Vector measurements of Altitude and Azimuth (built-in accelerometer/compass module).
- Included applications for reading data in Perl.
- The Half Width Half Maximum (HWHM) of the angular sensitivity is ~10°. The Full Width Half Maximum (FWHM) is then ~20°. The sensitivity to a point source ~19° off-axis is a factor of 10 lower than on-axis. A point source ~20° and ~40° off-axis would register 3.0 and 5.0 magnitudes fainter, respectively.
- Size 5.5 x 2.6 x 1.1 in.
- Maximum light sampling time: 80 seconds.
- Minimum light sampling time: 1 seconds.
- Specifications are subject to change without notice.
NotesThe compass readings are very sensitive to any nearby hard and soft iron. The unit works well by hand operation.There is a slight magnetic offset (pinched and stretched at ≈±5° in some directions) due to internal components which have yet to be compensated for in the UDM software, but the compensation is planned for a future release of UDM.
What's in the box