title: Google Maps Markers in wrong location, but lat/lon appears correct
body: <p>I am using custom markers to show a semi-live view of the location and orientation (heading) of certain vehicles of interest overlayed on Google Maps.  (In my case, I'm depicting aircraft, the same way Uber does for cars, or how FlightAware does for commercial flights).  </p>
  
  <p>The coordinates for the markers are being broadcast in JSON format to participating browsers from a server that I control.   The JSON data is processed by a JavaScript function at the browser to create / update the markers on the Google map.   The refresh (broadcast) rate can sometimes be as fast as once every 2-seconds, or as slow as once every 30 seconds, depending on the particular user's needs of the moment.</p>
  
  <p>Sometimes, it is possible (and valid) for two markers to be thousands of miles apart from each other.  For example, one marker could be in Montana, and the other could be somewhere in Africa, and this is a valid condition.    </p>
  
  <p>However, sometimes, when I am zoomed into a region of the world so I can look more closely at one marker, a "ghost" marker appears nearby that "isn't really located there".  The ghost marker is labeled as one of the other markers that may be hundreds or thousands of miles away, but it's showing up in my zoomed in view for some strange reason.   If I momentarily zoom in our out, the ghost disappears, but it may re-appear again.</p>
  
  <p>Interestingly, the ghost image has the proper orientation for the vehicle it represents, but it's just located in the wrong part of the world.    </p>
  
  <p>Are there any special things I should be doing when I'm updating multiple markers separated by large distances so they don't show up like this in the wrong place?  </p>
  
  <p>I have traced this as far as putting console messages in the browser so I can see the lat/lon of each marker being depicted.  I output the latLng object just before it's applied to each marker, and the lat/lon I see in the console log is correct, even when the actual marker shows up in the wrong place.</p>
  
  <p>I don't know if this is a contributor to the problem, but the marker images I'm using are custom PNG files, not standard Google makers.   Has anybody run into this before?</p>