Contents


Google Earth Pro Started from AirPhotoSE

Note:

If the Google Earth Plugin still works on your machine, please note that it requires far less manual intervention than Google Earth Pro.  Use it instead of Google Earth Pro as long as it runs on your machine and ignore the rest of this section. Tje Plugin will not work with Windows 10.  The menu entry and button for it are not visible if Windows 10 is detected.

Google Earth Pro should work with all Windows versions including Windows 10, .You can run Google Earth Pro independently from AirPhotoSE. If you want calibrated image output for georeferencing with the many grids and datums available in AirPhotoSE, this guide is intended to show how to get similar results with less manual intervention than by finding points suitable for calibration in a GE image.  It assumes some familiarity with Google Earth's myriad of menus and submenus.  



Open the AirPhotoSE Google Earth Pro window either by clicking on the grey globe to the right of the Google Earth blue globe on the main toolbar or select it from the File menu with Ctrl+Alt+G or a click on the Google Earth Pro menu item.



Always remember: Google Earth Pro is an independent programme called by AirPhotoSE..  It only reads files written in the KML language (see User Guide), several of which are installed on the AirPhotoSE home directory. It can also save files in that language which can be read by AirPhotoSE. It returns very little information to AirPhotoSE.  Unfortunately, this makes it necessary for the user to carry out some critical operations manually which were automatic when using the Google Earth  Plugin.  Error checking can not be done during the process, and failure may produce unexpected or useless results.  

Starting Google Earth Pro from AirPhotoSE



The GE Pro window has three entries.



This entry closes the window and if GE image files have been saved, they are displayed as AirPhotoSE windows.  It also offers to restore the default version of the KML file in case this has been modified incorrectly.by the user. 

 

The Action option currently offers three search (Find) methods which are the same as those in the Google Earth Plugin.  Please read the information from the other chapters about the Plugin in this  guide. The Action menu also incudes a test for Google Earth Pro, the entry for choosing how to calibrate saved GE images with calibration points or saving GE images without calibration by default.

To learn how to use Google Earth Pro from inside AirPhotoSE, try the Test Coordinates option:



and after a click on Find, enter a file name in the pop-up file window to display Google Earth at the coordinates and altitude shown.  The values may be changed in the entry fields to look at other places...  



The file name chosen is also copied to the Clipboard so that it can be  used inside Google Earth for various file operations by pasting it into various file name fields with Ctrl-V.. Although you can choose your file name the first time it is requested in AirPhotoSE, if you use different file names in Google Earth, subsequent operations in AirPhotoSE can not see what you have done in Google Earth.

In Google Earth Pro:



The file menu of Google Earth offers many options which are described in the Users Guide 



The most important is  Save option on the File menu offers several functions which will be described below.



The Edit menu has the Properties option which when opened offers detail and tools for the manipulation of Google Earth's options for important features.  It is the only way to see what is going on inside Google Earth.



The View menu options govern appearance and additional features. Many additional details are made visible and can be selected by clicking on the Sidebar option to open them.  However when the Sidebar is open, the size of some saved image choices will be reduced. 

Note:

It is strongly recommended to save any data with the Google Earth File Save menu which you may have in the My Places and Temporary Places entries visible in the Sidebar,



The Tools menu offers a number of simple aids like the Ruler for measurement on a loaded image and opens the very important Options menu which contains choices for storage and important matters relating to the way the programme behaves and how image coordinates are displayed..



The Add menu contains frequently used functions for controlling the behaviour of Google Earth, a number of which have been already implemented in the KML files supplied with AirPhotoSE. You do not need to use it when calibrating via AirPhotoSE.



Help contains a list of common Keyboard Shortcuts which can save a lot of typing and errors when using Google Earth.



Some things to set from the GE Tools-Options menu before you start:

The the first of five Options dialogue windows called from the Tools menu should be configured as shown here for use with AirPhotoSE.



The third Options page for Navigation should be set so that views images are **not** automatically tilted when zooming to prevent perspective distortion in saved results.

Note:

If you have graphic hardware from NVIDIA and drivers are automatically updated, uncheck the Enable stereoscop 3D options in the NVIDIA Control Panel window to prevent displaying GE images as anaglyphs.

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Some of the other submenus and dialogue windows of Google Earth Pro  will now be discussed in detail relevant to use with AirPhotoSE.



The File menu opens the submenu for saving images.
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When an image is to be saved, Google Earth Pro offers a drop down menu for items which the user may wish to show on the saved map.  In most cases, all boxes must be unchecked to hide unwanted data in the saved result.





Perhaps the most important image saving menu offers the choice of resolution of the result.  This feature is only available in the Pro version of Google Earth. 
 


The second "save image" option which appears after the resolution is chosen opens a file dialogue window.



The users choice of an output file name made in AirphotoSE's initial Google Earth window is copied to the Clipboard from which with Ctrl=V it can be pasted into the Google Earth output window.  This permits changes in file names to be made to label items from a set of different options has been used in Google Earth. If you use other names or change punctuation, AirPhotoSE will not find the output and ignore your results for further use in calibration.



When Google Earth is closed either from the File Menu or with the keyboard shortcut Alt-F4, the user is asked if he wants to save items in Google Earth's Temporary Place list.  For most purposes, click the Discard button unless you have made changes yourself which you want to keep.



In AirPhotoSE, the Action menu has options for displaying different kinds of data via the KML file in Google Earth. The menu entry below the Test Coordinates option offers either No Coordinates or automatically entering four marker points with computed latitude and longitude coordinates that will be used for calibrating the Google Earth result from within AirPhotoSE. 



These will be shown on the result image after Google Earth is closed and AirPhotoSE opens the chosen file for calibration. They are widely spaced so as to be outside in the central area of the image in Google Earth.  They contain custom place marks with a red circle and cross-hairs which Airphotse SE can use in calibration.


 

These are given automatic labels nw = northwest, ne = northeast, se = southeast and sw = southwest so that their latitudes and longitudes can be identified in AirPhotoSE as will be described below.  If you double-click on a marker in the Google Earth My Places or Temporary Places lists, the image will center on a marker.



A right-click on one permits opening the place mark editor in Google Earth.
 


In it's View option you can see all the details for the point



which you can move by dragging on the yellow frame.  However, this changes the latitude and longitude values which are **not** returned to AirPhotoSE in this version for use in calibration to be described here. 

In AirPhotoSE: Calibrating images saved after you close Google Earth:



Open the Calibration menu and select Enter/Delete Cal Point



Move the magnifier to the northwest corner marker.



Center it on the cross-hairs of the marker and left-click on it.



This will display the geographic coordinates of all four markers made in Google Earth.  Check the box for the northwest marker.



Repeat this four all four markers at nw, ne, se and sw points.



When the Google Earth image is saved and the programme returns to AirPhotoSE, the system coordinates are set temporarily to Lat-Lon Decimal as used in Google Earth.  



Check for possible selection mistakes by writing a temporary grid which must show horizontal and vertical rectangles.lines when zoomed out.



The default options can be used in the Grid appearance window.  If all is OK, erase the temporary grid  with the Undo button or equivalent menu item.



As a further check, you may. choose the UTM WGS84 grid from the Options dialogue



The lines of the grid will usually be rotated a small amount relative to the screen, depending on geographic location.

Examine the four calibration points.  Hide the blue-green calibration circles from the main AirPhotoSE calibration menu and erase the temporary grid with Undo when you are satisfied that all is OK.



Completing calibration:

If you have chosen an EPSG grid before using Google Earth.Pro,  open the Calibration menu and click on LatLon-WGS84 to EPSG



to convert the Google coordinates to the chosen grid.  All calibration points from Google Earth must lie inside the geographic boundaries of a chosen EPSG grid.  Save the Google Earth image with a new name if you want to keep both kinds of coordinates. 

If you want to see map features superimposed on the Google Earth result, check Borders and Labels, Places and Roads in the Layers menu when still in Google Earth before returning to AirPhotoSE. You can also use the Import facility in Google Earth Pro to add data from GIS programs.. 
 




Final Notes:

You can make a clean calibrated Google Earth Pro image by hiding the calibration place marks in Google Earth with unchecking all the points in the My Places and Temporary Placemarks list and saving the image in Google Earth again with a modified name. 

The automatic calibration results may be loaded for either the image with the markers for placemarks or without them. Changing the image position or zooming in Google Earth is permitted, but the automatically generated Lat-Lon markers from AirPhotoSE  must not be moved or calibration will fail.