meypod / al-azan

Privacy focused ad-free open-source muslim Adhan (islamic prayer times) and qibla app
https://meypod.github.io/al-azan/
GNU Affero General Public License v3.0
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Considering elevation for Salah times #27

Open Raviu56 opened 1 year ago

Raviu56 commented 1 year ago

Assalamo alaykom, Jazakum Allahu khayran for your application.

There is one problem that most Prayer times app does not take into account which is Altitude/elevation above sea level of the location point. This is really a big problem and can make difference of minutes of prayer time. The app assumes everything is at sea level which is not the case usually. Consider those 2 locations:

36.34444/30.12013/~35m 36.33877/30.05053/~1650m

Distance between them is around 6300m while elevation difference is over 1600m which diffidently should have much effect on prayer time.

You can watch this video in Arabic language

https://www.youtube.com/watch?v=yIaVmmRXLcI

I think you should seek help from https://www.astronomycenter.net/ on how to take elevations into account

Raviu56 commented 1 year ago

Check this application it's for Sunrise and Sunset time calculations. Its default calculation method called time4a-time4j takes elevation into account and you can with simple click turn on/off elevation and see how much it affects Sunrise/Sunset times . You can make use of its code too

https://github.com/forrestguice/SuntimesWidget

meypod commented 1 year ago

Va alaykum assalam, Thanks for bringing this up To address this we need to address it in the library this app uses: https://github.com/batoulapps/adhan-js

meypod commented 1 year ago

I'll make an issue there, and discuss it with them

meypod commented 1 year ago

Hi @Raviu56 please take a look at these: https://github.com/batoulapps/adhan-js/issues/126#issuecomment-1213634448 https://github.com/batoulapps/adhan-js/issues/16#issuecomment-640287803

from what it seems, it does not seem to be an easily solvable issue

meypod commented 1 year ago

so the affected times are : Fajr, sunrise, sunset, maghrib, isha

Raviu56 commented 1 year ago

Yes, For Fajr and Isha effect is minimal as in the videos. But for Fajr limit of Sunrise and Maghrib there is a considerable effect.

I've opened a new issue there

https://github.com/batoulapps/adhan-js/issues/146

meypod commented 1 year ago

thank you