Product Details

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• The Sky Quality Meter-L measures how clear the night or site is. Compare the sky brightness at different sites with measured results! If you're a CCD use, you can make a correlation between the Unihedron SQM-L reading and when the background reaches some ADC level.

  How to Use the Sky Quality Meter-L

  • Keep track of the evolution of light pollution in your area.
  • Set planetarium dome illumination to mimic the skies you are likely to experience elsewhere in the city.
  • Monitor sky brightness through the night, night-to-night, and year-to-year.
  • Determine which nights are the greatest for finding the faintest of lights.
  • 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.

  Features of the Sky Quality Meter-L

  • Receive audible signals while measurement is in progress.
  • The sky brightness measure is displayed in visual magnitudes per square arcsecond.
  • Its infrared blocking filter restricts measurement to its visual bandpass.
  • Temperature is measured in both Celsius and Fahrenheit.
  • The model number and serial number can be displayed with different button press sequences.
  • Receive precision readings at even the darkest sites.
  • Its power-saving features provide maximum battery life.
  • Reverse battery protection.

  Full List of Specifications for the Sky Quality Meter-L

  • The Half-Width Half Maximum (HWHM) of the angular sensitivity is ~10 degrees.
  • The Full-Width Half Maximum (FWHM) is then ~20 degrees.
  • The sensitivity to a point source ~19 degrees off-axis is a factor of 10 lower than on-axis. A point source ~20 degrees and ~40 degrees off-axis would register 3.0 and 5.0 magnitudes fainter, respectively.
  • Operates from 9V battery (included).
  • Size: 3.6 x 2.6 x 1.1 inches
  • Maximum light sampling time: 80 seconds
  • Specifications are subject to change without notice.

  OPT Product Number: UH-SQM-L 

   

• specifications

  Warranty

  1 Year Warranty

• included items

  • An affordable meter for measuring sky brightness!
  • Unprecedented sensitivity in a handheld meter!
  • Measures the brightness of the night sky in magnitudes per square arcsecond.
  • Designed by Dr. Doug Welch and Anthony Tekatch.