Recent Posts

31

SQM-LU / SQMDroid for SQM-LU

« Last post by admin on August 04, 2018, 09:55:10 pm »

Thomas Hänel has written SQMDroid, an Android OS program that reads data from the SQM-LU meter. Thomas and his father Andreas presented SQMDroid and their findings at ALAN 2016 in Cluj, PDF here

The mobile Android device must be OTG (On The Go) compatible, and have an (well calibrated) orientation sensor to be used in the vector or NixNox mode.

The software is as-is, and it must be installed separately (not Google Play store), apk here.

SQMDroid has been used quite often with different Android smartphones, tablets (mainly Samsung) without problems.

32

Connected meters (SQM-LE/LU/LR/DL) / Re: Observing Conditions interface in ASCOM 6.2

« Last post by admin on May 10, 2018, 11:04:54 pm »

A kind person has written an ASCOM driver which should work for the SQM-LU, SQM-LR, and SQM-LE. It is available from here:

http://www.dizzy.eu/downloads.html

33

Connected meters (SQM-LE/LU/LR/DL) / Re: GPS integration

« Last post by admin on May 08, 2018, 07:43:12 pm »

Unihedron sells a bracket for mounting the SQM connected metes to a car window for travelling readings:
  http://unihedron.com/projects/sqm-wm/


As well, the Unihedron Device Manager software (UDM) now comes with a tool that converts the .dat (data-logging files) to .kml files used by GoogleEarth so that the following map image (with legend) can be created:

34

Connected meters (SQM-LE/LU/LR/DL) / Re: GPS integration

« Last post by admin on April 12, 2018, 05:38:43 pm »

I've been informed that there is a Bluetooth enabled GPS (Dual XGPS160) which also works well on a Mac with UDM.

Here is a link to that the Dual XGPS160:
http://gps.dualav.com/explore-by-product/xgps160/

35

Connected meters (SQM-LE/LU/LR/DL) / Re: GPS integration

« Last post by admin on March 05, 2018, 06:04:10 pm »

Another GPS mapping system:
  "Road Runner"
  Report by Daniel Rosa Infantes of Sociedad Malagueña de Astronomía, 2011:
  http://darkskyparks.splet.arnes.si/files/2011/09/RoadRunner.pdf

36

Connected meters (SQM-LE/LU/LR/DL) / Re: SQM-LE Multiple connections

« Last post by admin on February 22, 2018, 03:12:00 pm »

Is it possible to have multiple connections of UDM to a SQL-LE?

It is possible, but the SQM-LE can only handle one connection request at a time or there will be no answer to requests. This would work if UDM was just used to take occasional manual readings.

What are the gotchas of doing this?

If you are doing continuous logging on both UDMs connected to one SQM-LE, then there will likely be times when the SQM-LE can only answer one UDM and data will be lost.

If you want this for the purpose of a reliability in case one computer crashes, then you might be able to set a smaller trigger frequency at prime number timings, for example, one UDM set to trigger every 61 seconds, and the other every 67 seconds.  There would be some overlap, but there would still be lots of readings to work with.

37

Connected meters (SQM-LE/LU/LR/DL) / SQM-LE Multiple connections

« Last post by jclegrice on February 22, 2018, 01:31:27 pm »

Is it possible to have multiple connections of UDM to a SQL-LE?

What are the gotchas of doing this?

Regards
Justin

38

SQM-LU-DL (Datalogging light meter) / Re: Firmware updates

« Last post by admin on February 13, 2018, 12:00:59 pm »

New firmware released, see top post for details.

Some features of the new firmware are not supported on the old version of UDM, so make sure to update UDM as well. The latest version can be found here: http://unihedron.com/projects/darksky/cd/

39

General Discussion / Re: Enclosure for SQM

« Last post by kyba on October 18, 2017, 10:33:32 am »

Hello Beclyn, Anthony, and all,

Thomas Posch used a setup to reduce the influence of moonlight: https://arxiv.org/pdf/1304.7716

Something like that might work, but I would caution that you be careful, because depending on how you did it, you could potentially see light from the streetlamps reflected by the collimator surface.

However, it should be emphasized that the results will be different, that is darker, than what you would get with an SQM at the same location (assuming you could turn off the nearby lamps). Depending on what you are trying to do, that might be ok or problematic.

I would strongly recommend against tilting the SQM unless you can very accurately re-position the SQM after taking it down for cleaning/etc., and that you record the tilt angle in the metadata.

Best,

Chris

40

General Discussion / Re: Enclosure for SQM

« Last post by admin on October 18, 2017, 09:57:30 am »

The L (lensed) model meters have a field of view shown in the plot below on the right side (SQM-L):



You should ensure that your shield does not interfere with the light coming in to the meter from the sky above.

While the Full Width Half Maximum (FWHM) is ~20°, the unit is still sensitive to light at +/-30° or 60° (as can be seen at the bottom of the right hand plot).

You can also set the meter (and housing) on an angle to point to a part of the sky that is free from artificial light and obstructions.