Recent Posts

Pages: 1 2 3 [4] 5 6 ... 10
General Discussion / The new world atlas of artificial night sky brightness
« Last post by admin on June 13, 2016, 11:05:13 pm »
"This atlas shows that more than 80% of the world and more than 99% of the U.S. and European populations live under light-polluted skies."

Read the full paper with maps The new world atlas of artificial night sky brightness.

by Fabio Falchi, Pierantonio Cinzano, Dan Duriscoe, Christopher C. M. Kyba, Christopher D. Elvidge, Kimberly Baugh, Boris A. Portnov, Nataliya A. Rybnikova, Riccardo Furgoni
I am certainly no against doing such a thing, I just have to find the time and resources for it. It's on the plate.
Connected meters (SQM-LE/LU/LR/DL) / Observing Conditions interface in ASCOM 6.2
« Last post by Bkoch on May 22, 2016, 03:05:18 pm »
 Will support be added for the new ascom Observing Conditions interface in the near future? SGP users would find it beneficial. Thanks in advance.

Connected meters (SQM-LE/LU/LR/DL) / Raspberry Pi installation with PySQM
« Last post by admin on February 23, 2016, 02:12:19 am »
Rubén Díez Lázaro has come up with detailed instructions for installing PySQM onto a Raspberry Pi Single-Board_Computer:

PySQM can be found here:
Connected meters (SQM-LE/LU/LR/DL) / Re: Firmware updates
« Last post by admin on December 12, 2015, 01:37:46 am »
The "Retrieve-All" function sometimes contained spurious values during the retrieve process.

The following firmware update will fix (feature 36) that:
  For the SQM-LU-DL:

  For the SQM-LU-DL-V:

The firmware update does not affect the database records.

Please ensure that you are using the latest version of UDM to access any new features that have been added to the firmware:
SQM-LU / Re: Extending the USB cable
« Last post by admin on November 23, 2015, 09:37:45 pm »
Recently a customer had problems with the IOGEAR GUCE51 device, but the GUCE62 device worked properly. There could have been issues of USB level (2.0 vs 1.0) or FTDI driver issues. We are now recommending the GUCE62 device for extending the SQM-LU meters.
Connected meters (SQM-LE/LU/LR/DL) / Re: UDM updates
« Last post by admin on September 27, 2015, 02:56:26 pm »
Updated UDM, now at version

See edited first message for change log and links.
Connected meters (SQM-LE/LU/LR/DL) / Re: FTDI driver installation problems
« Last post by admin on September 10, 2015, 07:55:45 pm »
Clearing Windows COM list

After installing different FTDI devices in Windows, the system fills up with COM port numbers.

You should prevent auto update as identified in the previous post, then ...

If you are very careful, it is possible to clear off all the "used" COM ports by following the instructions at this link:

Connected meters (SQM-LE/LU/LR/DL) / Re: FTDI driver installation problems
« Last post by admin on September 10, 2015, 07:41:57 pm »
Installing Windows FTDI driver manually (preventing auto-update)

Just recently, Microsoft seems to have stopped providing FTDI drivers automatically for Windows 7 (and possibly other versions).

This can be a problem because connecting an FTDI device to the USB port usually initiates an automatic check for updated drivers and failure to find such a driver at Microsoft results in a failed driver installation.

You can turn off automatic updates to prevent this as follows:
  • Open the: Control Panel -> System Security -> Windows Update
  • Select Change settings
  • Deselect Recommended updates
  • Press OK

You can now manually install the FTDI driver from

Then plug in the SQM-LU device.
Congratulations to B Espey, PhDa,b and J McCauley, MSca for the publication of their paper:

Initial Irish light pollution measurements and a new Sky Quality Meter-based data logger

in Lighting Research and Technology, on February 2014 vol. 46 no. 1 67-77

From the Abstract:
In the Celtic Tiger years, Ireland underwent an explosive growth in housing and an increase in light pollution, nationally. We outline work undertaken towards the first ever ground-based survey of light pollution in the island of Ireland and illustrate this with some representative data taken between 2009 and the present. The aim of our work is to establish a database to serve as a reference to monitor future changes, to compare with in-orbit measurements, to study the potential impact on the environment and to permit the calculation of the effects of future changes in lighting usage and patterns. We also report the development of a microcontroller-based data-logging instrument based on a Unihedron Sky Quality Meter-LR detector, which can be used by amateurs or can serve as a stand-alone instrument for night-sky brightness surveys.

Read the full paper here:

This paper explains a method of using the SQM-LR and a GPS to gather night-sky brightness readings over a large area.
Pages: 1 2 3 [4] 5 6 ... 10