Unihedron Sky Quality Meter - L SQM-L
Item No. 787-10050
Eligible for Scope City Rewards at Check-out
Manuf. No. Unihedron SQM-L
Finally, an affordable meter for measuring sky brightness for astronomers!
The Sky Quality Meter - L measures the brightness of the night sky in magnitudes per square arcsecond.
Unprecedented sensitivity in a handheld meter!
Designed by Dr. Doug Welch and Anthony Tekatch Uses:
- 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.
- Audible signal while measurement is in progress.
- Sky brightness displayed in visual magnitudes per square arcsecond.
- Infrared blocking filter restricts measurement to visual bandpass.
- Temperature in both Celsius and Fahrenheit as well as model number and serial number can be displayed with different button press sequence.
- Precision readings at even the darkest sites.
- Power-saving features designed in for maximum battery life.
- Reverse battery protection.
- The Half Width Half Maximum (HWHM) of the angular sensitivity is ~10 degree. The Full Width Half Maximum (FWHM) is then ~20 degree. The sensitivity to a point source ~19 degree off-axis is a factor of 10 lower than on-axis. A point source ~20 degree and ~40 degree 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 in.
- Maximum light sampling time: 80 seconds.
- Specifications are subject to change without notice.