The app (iPhone only) uses the camera to collect light at night. The aim is to provide a cheap alternative to
expensive light meters. When you submit your measurements the data is used for scientific research.
The app got awarded by the IDA and has been featured on BBC, CBS and Scientific American.
The app is developed by Norbert Schmidt and Harro Treur, and supported by many scientists, Globe at Night, Stars4all and the International Dark Sky Association.
This setting is for people who own a unihedron SQM or SQM-L. If you own a unihedron SQM the calibration on the iPhone can be adjusted to the outcome of the Unihedron Sky Quality Meter. The SQM uses dedicated hardware and is known as the gold standard. You can roughly calibrate the app using the unihedron sqm. iPhones can differ slightly (but constantly). It is best to take a series of measurements using both devices. Example If the SQM shows 20.30 and your iPhone shows 20.15 you can put .15 in the 20.00 and up field. or If the SQM shows 20.15 and your iPhone shows 20.13 you can put -.15 in the 20.00 and up field. Same goes for measurements with sqm 20 or lower, then you should use the 10.0>20.0
No. There are a lot of different Android devices, more than 4000 in total (2013). With so many camera types on the market, it will be impossible to make a decent Android port of our software. Adapting our software to all cameras will be impossible or cost a fortune.
Dark Sky Meter is an idea of Norbert Schmidt (software developer) and Harro Treur (engineer). We are amateur astronomers and were looking for a cheap alternative to expensive light meters.
It is not intended for iPad. Earlier models have a poor camera. And the software cannot discriminate devices (Apple policy).
The iPhone has a consumer camera and is not designed to collect a lot of light at night. Later models have very sensitive chips, but they aren't as good as the professional, dedicated light measuring devices. On a really dark site, take a minimum of 2-3 measurements and average them.
You pay 2$ to cover my hosting costs and the many, many hours of private time i spent on it. You save about $110 for a commercial SQM device.
If you choose to submit your data, the dark sky meter data is stored and sent to the Globe at Night project. No personal data is collected. Only Lat/Lon, SQM value and some meta data like sunrise/sunset et cetera. Data is only sent after submitting. And thats optional.
The cloud prediction panel gets its data from a Chinese service called 7timer. It moves sometimes from server to server and is not always up.