Solar Polar Alignment

Bodling Tech

About this app

Solar Polar Compass uses the sun's position in the sky to calculate where north is. By aligning the lines on screen with the shadow of a vertical object, your phone and screen guidelines will be exactly aligned north-south. Ideal for astrophotographers who want to set up in the daytime, and useful for anyone who needs to know where true north is to a high degree of accuracy. Solar Polar Compass is much more accurate than a magnetic compass, which does not align with true north, and on a phone may need calibration or oscillate around magnetic north.

To use, wait for your GPS coordinates to load, or type them manually. The app will use your phone's time and timezone to calculate solar azimuth using the NOAA formulas. On screen, angled lines will appear. Line these up with a shadow (multiple lines are provided for optimal phone positioning). The rounded end of the central line should be towards the sun. The top of your phone is pointing north in the northern hemisphere, south in the southern hemisphere. The sides of the phone and guidelines on screen are aligned precisely north-south. The display updates continuously.

Ratings and reviews

Clever Daytime True N-S Axis Aligning Tool. Set on level surface and align shadow of a vertical object with the lines on the screen. Your phone is now aligned perfectly! Looks like it is using "the equation of time" for its calculations. It bases the calculations on your local time and GPS coordinates. Suggest changing background to white and lines to black so shadow is easier to see on screen. Great app - thanks! It'll be invaluable for solar photography!

Used it for my Ha solar scope. Works great in the evening but not so much in the morning. It is like it has a problem where it is using a trig function assuming the wrong quadrant when used in the morning. Unfortunately I do more imaging in the morning than the evening. If it worked in the morning I would give it 6 stars if I could.

Just downloaded this as I am having difficulty setting my eq mount to true north. I am already impressed. I wish I had this app 40 years ago when I was in north africa. We had big bulky brass sun compasses which were a nuisance and a pain to line up. Well thought out guys. Knowing the time of solar noon is priceless. If you could put solar noon and actual time on the same level it would save scrolling.

What’s new

Updated to comply with Google background location requirements.