From time to time, I will find apps that are useful for astrohotography. Some are well known but others maybe not so much. In the “App Tip” series, I will highlight some of these apps that I find useful in the hopes I can help other people capture better images. I use an iPhone, so I will be highlighting apps that are for iPhone, even if they are not available on Android.
Some apps (such as Clear Outside) will give you a “SQM” value for your sky conditions. The range is rather odd (16.00-22.00 with higher numbers darker skies).
I’ve always wondered how accurate these values are since they come from map data. The best way to find out is to buy a SQM meter and measure.
But if you don’t have one, there is an alternative called “Dark Sky Meter“. It’s pretty easy to use. Press “1” to take a dark (after covering your camera lens) then hold it up to the night sky and press “2” to analyze. Select your sky conditions (From Clear all the way up to foggy) and you will get a readout.
You can also choose to share with “Scientists across the world” – which makes the $1.99 price a little frustrating since I am doing all the work here, but I did it anyway
Here is the result for my skies
It even has a nice red UI so as not to upset your astro-friends
My sky had a few clouds, and was measured at 19.64 (Bright Suburban Sky). Which it is.
“Clear Outside” reports 19.22 (Bortle 6) with 42% cloud cover, so it seems reasonably close but only a single data point.
This app is probably a little more useful if you take images in a variety of locations and honestly, I am not convinced it is worth the money but it was interesting to check it out.
It does have a map and a clouds feature (which lists seeing and transparency, which Clear Outside does not seem to report for me), as well as temp and moon phase.
The help section says that the data is used to keep Dark Sky Meter up to date, so that seems like an important thing to contribute to !
Astrophotonic 