Path: ...!Xl.tags.giganews.com!local-2.nntp.ord.giganews.com!news.giganews.com.POSTED!not-for-mail NNTP-Posting-Date: Tue, 25 Jun 2024 23:59:15 +0000 Date: Tue, 25 Jun 2024 19:59:15 -0400 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: =?UTF-8?B?YmFk8J+SvXNlY3Rvcg==?= Subject: Re: app for precision coordinates Newsgroups: comp.mobile.android References: <1ib29f50d2bbn.dlg@v.nguard.lh> Content-Language: en-US In-Reply-To: <1ib29f50d2bbn.dlg@v.nguard.lh> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Message-ID: Lines: 115 X-Usenet-Provider: http://www.giganews.com X-Trace: sv3-B00w4OKsgXPBhqz3pDBR/KYSP9DCxEVTzPzhPqTJq3m+wuGXTmzcB3CYRrc1uWJ4tqGiwdvqSVNDOZ8!+N6Y4+skIHa82UcwFT06asl2my/WrWAqxHPWYqs7OsO8mrVkGOG4f8uZOYketjiFguT2cHsKWDGm X-Complaints-To: abuse@giganews.com X-DMCA-Notifications: http://www.giganews.com/info/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 Bytes: 7815 On 6/24/24 13:27, VanguardLH wrote: > bad sector wrote: > >> On 6/23/24 16:34, VanguardLH wrote: >>> bad sector wrote: >>> >>>> On 6/23/24 10:18, knuttle wrote: >>>>> On 06/23/2024 9:39 AM, bad sector wrote: >>>>>> >>>>>> How would I map with precision about 900 planted trees on >>>>>> google-earth-pro? As a manual method I would think of taking a hundred >>>>>> readings on each with my phone and averaging them out, but that is a >>>>>> LOT of work (did it once with a bubble-sextant to win a bet). Is there >>>>>> an fdroid app to do this sort of thing (not interested in signupware)? >>>>>> Any other ideas? >>>>>> >>>>> I don't know about the  android version, but on the PC version you can >>>>> add pins to identify a specific location. >>>>> >>>>> On the PC version of Google Earth Pro, you can determine the longitude >>>>> and latitude to six decimal places or get good numbers for location >>>>> about 300 feet apart.  This 300 feet was calculated by zooming Google >>>>> Earth to its maximum and reading the coordinates of each location. >>>> >>>> About 1/3 of the trees are now just big enough to show on GE but the >>>> rest are not visible yet. It is to place THESE that I need the >>>> lat-longs. And I'm looking for about one foot of precision :-) which is >>>> not easy with the imagery resolution provided out here in the sticks. If >>>> I were living in the densely populated areas a six inch seedling would >>>> show but all I get is about a 1.5-2.0 foot circle to show. >>>> >>>> During a drinking marathon I once bet with the owner of a hotel I was >>>> staying at that I could measure the width of his hotel with a >>>> bubble-sextant to within a foot. So I took like a hundred readings on >>>> two corners, plotted them and marked the center of each 'blob'. Won the >>>> $200 bet which today would be like $2000. If I were a codepuncher I'd >>>> try to write an app that plots for maybe 30 minutes and then coughs up >>>> the centerpoint of the same sort of blob as the position. >>>> >>>> I'll be planting another hundred or so in the next three months so I'd >>>> like to refine my mapping. 220 of the trees are yellow-cedars not native >>>> here and many fans are watching to see how they will survive. I want to >>>> map them on GE and update the pictures from time to time. >>> >>> I would think GPS would work to record the locations of the trees. >>> While different GPS receivers have varying levels of accuracy, even your >>> phone's GPS radio should suffice. After all, the trees have to be >>> planted far enough apart to account for their canopies. >>> >>> https://crec.ifas.ufl.edu/media/crecifasufledu/extension/plant-pathology-/greening/pdf/GPSAccuracyforTreeScouting.pdf >>> https://fruitgrowersnews.com/article/precise-gps-systems-increase-planting-efficiency/ >>> >>> Since you are at site when planting the trees, use GPS to record where >>> you planted. Then use the GPS coordinates, or convert to long-lat, to >>> position in a map. >>> >>> GPS radios in smart phones are accurate to within 3 to 5 meters (1o to >>> 16 feet). Don't know far apart you are planting the seedling to account >>> for their canopy sizes later in life. If a smart phone's GPS isn't >>> accurate enough, you can buy GPS receivers that are more accurate. >>> >>> I figure if a hand-held GPS navigator is good for recording trails that >>> it is probably sufficient to record tree locations. >> >> thanks for the time to respond >> >> I once bought a garmin gps camera attachment for my slr camera but it >> too was wishy washy; never even tried composing blobs with it. With 900 >> trees (and growing) the only 'involvement' I have time for is putting >> the smart-phone down and leaving it there to collect its wanderings over >> maybe fifteen minutes or less. The trees are at different distances but >> what I want is 1-foot accuracy not so much because it's indispensible >> but because I'm a sucker for at least a semblance of reality. >> Google-Earth placemarks is one tool I use giving the trees icons >> representing the tree species. Ideally I'd like to attach an actual >> photo of the tree to appear in a popup on click or something along those >> lines and all of it uploaded instead of locally stored. >> >> Not sure if math averaging would give the same result as hitting the >> center of plotted coordinates but with the processing utility in a phone >> an APP could ideally produce the ultimately VERY accurate result ...just >> like I once did with a bubble sextant meant to produce plots in terms of >> miles at the center of triangles of probabilty. That stunt took half an >> hour per reading and I did maybe fifty on each of two corners, I forget >> the actual number, it was a royal pissing contest :-) > > I think averaging would only work well if you managed to get the GPS > device connected to different GPS satellites within reach. Then repeat > by using another different set of 3 GPS satellites. I would think > reusing the same 3 GPS satellites to get multiple readings from them > would result in the same offset (inaccuracy) in each reading. However, > maybe walking around in a circle around the focus point to take multiple > readings might work to average the multiple readings from the same set > of 3 satellites. > > Someone here mentioned DGPS (differential GPS) which uses ground-based > positioning stations. Those have a 200-mile range if there are no > blocks to the signal (mountains, trees, buildings). Never got around to > using those, so no experience with them. Don't remember seeing a smart > phone stating it can use DGPS, so you'll likely have to find a GPS > receiver that can find DGPS stations. I launch the F-Droid app *GPSTest* which tunes in a long list of satellites. https://f-droid.org/en/packages/com.android.gpstest.osmdroid/ I have no idea how it arrives at the annunciated Lat-Long but it's changing continuously and what I have in mind is an automated way of virtually plotting these positions over a few minutes and picking the plot-centerpoint as THE position. I haven't tried any of the math yet to get a feel for those 7 decimal readouts and what they mean in terms of feet but I figure that there must be some added precision to squeeze out of THEM as opposed to just any ONE of them.