Dark Sky Meter for iPhone available now!
Posted 11 August 2013 - 01:55 AM
Posted 15 August 2013 - 07:20 AM
Are you sure you have an iPhone 4 and not an iPod or an iPhone 3 or 3S??
Well, I trusted the web site claim that this app works even on an iPhone 4 (albeit with poor results dues to the low quality camera), and dutifully paid for the "pro" app. Neither the "lite" app nor the "pro" app can be installed on an iPhone 4, citing "incompatibility" and lack of a "front" camera. I
The app should install on every device with a front facing camera and telephony function (=Iphone 4 and up). I require a front facing camera and telephony to force support for iPhone 4 and up only. The reason behind it is to not allow iPhone 3 users to use the app. The iPhone 3 camera is terrible and absolutely not suitable for taking night pictures.
If you encounter problems, please let me know directly by sending a mail to firstname.lastname@example.org I'll be glad to help.
Posted 26 August 2013 - 02:40 AM
Are the results from the "Lite" version available online (for instance on the map or some other location) if they are "submitted"? I ask this because the fall Globe at Night campaign will be starting shortly and I am wondering whether school kids could use the Lite version to submit results (the actual SQM number) to Globe at Night. I noticed that the map gives reading, date, and time data but does not give GPS information. With Globe at Night there may be a bunch of readings in a concentrated area. It may be difficult to figure out which reading belongs to any particular person although I guess if you zoom in far enough you could figure it out.
Posted 27 August 2013 - 05:06 AM
Yes, the Lite measurements are on the map too. In the lite version the result is shown as 'times x a natural', but the submitted results are converted to SQM value.
Posted 27 September 2013 - 04:54 AM
The iPhone 5S will get experimental support in the next release. Because of the fact that the phone is not available in my country, i am not able to test it thouroughly (for each device, about 5000 measurements are made!). The 5C has the same sensor as the 5, so that one will work!
Posted 19 October 2013 - 02:48 PM
Posted 19 October 2013 - 05:48 PM
I purchased the Pro version of the app and naturally, it will be cloudy for the next week here. So I was wondering I close the SQM reading with the app compares to the Unihedron units?
I see a .1 or less variation. So close that I don't bother with my Unihedron, as I always have my phone with me. Great app!!!!
Posted 27 October 2013 - 12:07 PM
But it will take some time..
Posted 29 October 2013 - 05:25 PM
I live in a dark sky location,which us a village of 40 people, five or six street lamps, none of them anywhere near my house, as I live in the "dark/quiet" end of town. The next nearest town is 32 miles away, population 6,000, but the terrain here is very hilly and rugged so we're in a bit of a bowl. As such, there really is no city glow perceivable to the naked eye here other than for what few lights are in my town. There are spots not far from here that I believe are darker.
It's daytime right now, so I did tests in the house:
1). Bathroom with no windows, a dim red night light and white light coming through between door and door frame/floor. SQM 16.04 "inner city sky"
2) Walk in closet with no inside lighting, some white light seeping in through space between door and door frame/floor, though less than bathroom. SQM 20.58 "suburban sky"
3). Same location as #2, but this time I did a "dark" (pressing the camera up against my chest, wearing a dark blue sweater) and then again for the "sky" measurement. SQM 20.89 "rural/suburban transition"
4). Exactly the same as above, only this time I also covered up the FRONT facing camera as well. SQM 21.18 "rural/suburban transition"
5). Same location as above. Only this time I wrapped the phone up snugly, fully covering screen and front facing camera, in double-folded black t-shirt for both "dark" and "sky". SQM 21.36 "rural sky"
I was disappointed, thinking this probably should've given a darker rating, especially for the last two readings. One possibility would be that the light given off from the app during reading is reflected and also recorded. Even as low as it is, and in red, the light from the app is still pretty bright in such a dark environment. I used to have a film bag, which I would've loved to duplicate this test with, but I might've gotten a similar reading because of the app lighting being reflected and measured.
Maybe the app itself requires the iPhone to be actually oriented somewhat level with the rear-facing camera pointing outward (upward, in this case), as opposed to against my chest or other orientation?
Might there perhaps be a way for the app to momentarily go completely dark or interpose a "black" full-screen image just during the readings?
Looks like tonight will be clear, free of clouds, waning crescent moon rising at 7:30pm as well as darkness setting at about that time (that is, astronomical dusk ends). Will give it a go then. New Moon is this Sunday.
Will report back with measurements and post them via the app as well.
Posted 30 October 2013 - 06:04 AM
Posted 30 October 2013 - 12:46 PM
Posted 30 October 2013 - 12:53 PM
mtnmedic: Just curious, did you have the screen brightness turned down as low as possible during your measurements?
Aha! No...I noticed that it was about 3/4 dimmed.
So...I just now went back into the closet (stop laughing!), turned the screen brightness all the way down, did a "dark" then held the phone way up above my head, uncovered, and did a "sky".
Came out to SQM 21.37 "rural sky"
Posted 30 October 2013 - 01:20 PM
You will really have to test this at night, with the phone pointed upwards. Testing indoors is tricky because of the wide FOV of the app and the 'unnatural' light distribution. Any slit of light can ruin the measurement. And it sounds strange, but the night light is different from the home light. We did a lot of measurements indoor. Also note that the front facing camera is not used. Just cover the back camera.
Okay, I did just that and got SQM 20.84 NELM 6.47 with the Moon at 21%
Only thing, the Moon wasn't up yet by far. Unless it's pretty sensitive enough to pick up traces of moon glow.
Of course now thinking, I should probably have turned off my TV before I went outside last night to test (there is a road and a field, nothing else, at my house, nothing else around). The rest of the house lights were off. I stood well out in the road in front if the house. So, I imagine perhaps the light from the TV also was picked up.
Posted 31 October 2013 - 06:00 AM
Posted 05 November 2013 - 06:08 AM
There are formulas on the net which can take the amount of moon illumination and calculate an SQM value as if it was dark, but those are pretty tricky and unreliable. That's why we've installed a filter on our website map.
Posted 13 November 2013 - 04:03 AM
Posted 17 November 2013 - 01:55 PM
Posted 06 December 2013 - 09:05 PM
Looks like a cool app. Using my wifes old 4s.
Posted 07 December 2013 - 10:38 PM
Thanks for this app Norbert.
Posted 15 December 2013 - 01:03 PM
The Dark Sky Meter has been rewarded by the IDA this year. I've gotten the Dark Sky Defender award for it! I'm a happy man
This week i've got hold on a 5S. So i will start testing and start supporting this device after a lot of measurements during the holidays.
Posted 27 December 2013 - 11:48 PM
Posted 04 January 2014 - 11:21 AM
Posted 14 April 2014 - 07:34 AM
The app now displays 'this sky is X times as bright as..' in the pro version too. A CN user request.
Expect the update within 2 weeks.