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GPS not lining up

 The photos I am taking are not lining up to the actual headstones.   They are in the backyards of houses backing up to the cemetery, in a cemetery across the street, and generally shifted.  Is this normal?  I can't figure out how to at least move them to the right cemetery.  It is listed as the correct one, the pin is in a different one.

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This will happen when the GPS signal is not strong in the area you are photographing. For the issue with the wrong cemetery you will need to give the URL to customer support, as this is usually a problem with cemetery boundaries. One or more cemeteries without boundaries can often cause a mix up with the pins. When a boundary is set, the pins tend to go into their proper location. 

One of "my" cemeteries has all the markers bunched together in one quadrant and you cannot use the data to find anything there. It is right out in the open and would have nothing interfering with the GPS connection. How can I fix this?


You can fix both of these issues yourself, or reply back here to get help.

1. Define the boundaries of the two cemeteries. If you are sure of the boundary of each cemetery, you can go to the cemetery web site, open the Cemetry Information edit screen, and draw the boundary by dragging the corners/dots of the polygon into place.  Do that for each of the cemeteries, and refresh your BG website.

2. To correct the grave pin locations: Go to the cemetery page and enlarge the map showing the pins. Where pins are seriously out of place, you can open that person/grave record, and go down to the Grave Site edit screen. Open that and drag the pin to the place that you think it should be. Be sure to save after each pin movement.


James D - Please post a new message with the URL of the cemetery in question and let us take a look at your issue. Not sure  what you are seeing with the pin "bunched up", and why you don't think you can use the data? 


There are a few issues with this type of thing. 

1. The photos (or imagery) may not be exactly representative of where the headstones actually are in space. They go through a process called orthorectification and one called georeferencing. these two processes rotate, stretch and make the aerial imagery "fit" actual surveyed points on the ground. If this isn't done well/correctly they can be off several hundred feet. 

2. The GPS in cell phones as of today don't have very high accuracy. Using a very high end accurate survey grade unit, a person can get .5" accuracy, however the iPhone isn't guaranteed to come in anywhere near that. I've got one application I use, and it regularly tells me the accuracy is worse than 16 ft off. This can be somewhat rectified by using an external gps receiver such as those made by badelf or Trimble (R1 or R2) or Eos ARROW series. These can get very expensive, and complexity goes up with it. In addition, in order to really dial in the GPS, the signal needs correction, which can be done a couple ways, but is probably beyond this conversation (google RTK Real Time Kinematic and VRS Virtual Reference Station)… 

I'd really like to see billiongraves app support external GPS units via Bluetooth (trimble r1/r2, bad elf, eos arrow series, leica, juniper geode)...

Fwiw, this is one of the only viable options out there today to increase accuracy as far as i can tell. A company called broadcom introduced a gps chip last year called BCM47755 . It has capability of accuracy of 1 ft where todays phones might be in the 16 foot range. Thee is only one phone on the market that has this chip which is a phone called Mi 8 by a company called xaomi. I dont have one and cant vouch for its quality or actual accuracy, but if your in the market for a new android phone it could help bring the gps accuracy of your photos in tighter. Another thing you can do is go to a headstone youve gotten a bad shot on before, take a pic via billiongraves then switch to your normal phone camera app with geotagging turned on and take another pic. Ios( not sure about android) has a mapping feature where you can see where the photo was taken. You could open it up and see where the photo coordinates land if they land on/close to the headstone location, that might suggest its something in bgs imagery or gps recording algorithm thats wrong. If its in the same spot (across the road or something), that might suggest its something to do with your phone and its gps.
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