And if you were still at UNB, we could have used a theodolite to line things up similar to what I had to do (or, rather, have a student do) when helping to refurbish the Fredericton Soldiers Barracks wall sundial a number of years ago. ;-) -- Richard
----------------------------------------------------------------------------- | Richard B. Langley E-mail: l...@unb.ca | | Geodetic Research Laboratory Web: http://gge.unb.ca | | Dept. of Geodesy and Geomatics Engineering Phone: +1 506 453-5142 | | University of New Brunswick Fax: +1 506 453-4943 | | Fredericton, N.B., Canada E3B 5A3 | | Fredericton? Where's that? See: http://www.fredericton.ca/ | ----------------------------------------------------------------------------- ________________________________________ From: sundial <sundial-boun...@uni-koeln.de> on behalf of Richard Langley <l...@unb.ca> Sent: September 11, 2018 4:49 PM To: Steve Lelievre; Sundial List Subject: Re: How good is a cell phone compass Hi Steve: My iPhone compass app is indicating N correctly to within 1° right now with the phone sitting on the dining room table in a wood-frame house. Calibration not performed recently. Fortuitous? There must be some specs somewhere on the Web. -- Richard ----------------------------------------------------------------------------- | Richard B. Langley E-mail: l...@unb.ca | | Geodetic Research Laboratory Web: http://gge.unb.ca | | Dept. of Geodesy and Geomatics Engineering Phone: +1 506 453-5142 | | University of New Brunswick Fax: +1 506 453-4943 | | Fredericton, N.B., Canada E3B 5A3 | | Fredericton? Where's that? See: http://www.fredericton.ca/ | ----------------------------------------------------------------------------- ________________________________________ From: sundial <sundial-boun...@uni-koeln.de> on behalf of Steve Lelievre <steve.lelievre.can...@gmail.com> Sent: September 11, 2018 4:38 PM To: Sundial List Subject: How good is a cell phone compass Hi everyone, How good is a cell phone compass? I mean, if I have no metal nearby and I have the phone set to show True North, what kind of accuracy can I expect if I lay my phone flat and use the compass app? I'm working on a vertical west sundial for a community garden (a.k.a allotment) and have a deadline of end of September to get it installed, because the aim is to unveil it at the group's annual meeting. The dial is to be installed on two posts. I want to get the posts lined up as close to north-south as I can, to make aligning the dial easier. I will use adjustable bolts to fix the dial to the posts, so can I compensate for the line between them being a couple of degrees off - but no more than that. I already have one post installed and concreted in place. I had hoped to use the sun's meridian shadow cast by it to give me a precise line N-S for placing the second post. Unfortunately, rain has set in here and it looks as if there will not be a sunny day for at least a week. I don't think I can wait that long to get the second post installed; otherwise I'll be short of time for the other remaining tasks. Hence my interest in using my phone compass for alignment. Cheers, Steve --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial