What to Do About Coordinate Differences between Trimble Inpho and DAT/EM Summit Evolution Projects

Transcription

1 What to Do About Coordinate Differences between Trimble Inpho and DAT/EM Summit Evolution Projects By Alissa Oder, DAT/EM Support Department, Revision 1, 25 July 2016 Always Use Corner Pixel Origin 1 The Summit Project Has Use Heights or Dynamic Terrain Height On in the Interior Corrections Revised July 22, Atmospheric Correction Flag Mismatch 5 The Inpho Camera uses Coefficients Distortion Type 6 The Inpho Camera Uses Grid Correction Distortion Type 8 Earth Curvature Correction Code is Now Shared 8 Customer question: the orientation data we derive from Match-AT GPS shows different results when the orientation data is loaded from DAT/EM Summit Evolution. There is a height difference of about 10 cm between both systems. Do you know the reason for this? There are several sources of coordinate offsets to consider between Inpho Match-AT, UAS Master, and DAT/EM Summit Evolution. These offsets are usually due to using a mixture of old and new versions. We highly recommend that you use the newest Inpho and DAT/EM versions. There have been significant changes and good cooperation between the companies to make sure that Inpho projects are exported correctly and exactly matched by DAT/EM Summit Evolution. Always Use Corner Pixel Origin Summit projects have a setting in the XML file called dcn. This should always be 1 for projects that originated in any version of Inpho software. Dcn set to 1 tells Summit to use a center pixel origin. This is always right for projects exported by Inpho software. Dcn set to 0 tells Summit to use a corner pixel origin. This is always wrong for projects exported by Inpho software. 1

2 The value can be set accidentally to 0 by opening the obsolete.smtprj format file and then saving it. All versions of Summit that open a.smtprj file will assume that it should use the corner pixel, because it expects that the project was made by a very old version of DAT/EM Summit. There is no way for it to determine that the.smtprj was made by Inpho Applications Master. If you notice a file in the Summit project folder called.smtprj.bak, this is a good clue that an obsoleteformat.smtprj has been opened and saved as.smtxml. In older Summit versions, it is easy for the user to check a setting that suppresses the message about opening and converting.smtprj files. This setting has been removed so that newer Summits will always warn you. In addition, newer Summits prompt you to identify the project as having been exported by Inpho software. The newest versions of both Summit and Inpho software ask questions about the file format or what software wrote the file. These are safeguards to prevent problems with the pixel origin value. The newest Summit and Inpho versions ask questions to help prevent opening an obsolete format If there is any chance that an obsolete.smtprj file was mistakenly opened and saved to.smtxml, the Summit project should be searched for dcn=0 and changed to dcn=1 before digitizing begins. Try to use new versions of Inpho and DAT/EM software. If Inpho software asks what format to export, select SMTXML XML based format. If DAT/EM Summit has a checkbox called This project was exported by Inpho Applications Master, check the setting on. 2

3 For old projects, projects opened by converting.smtprj to.smtxml, projects where an.smtprj.bak file is discovered in the folder, projects exported by a version of Inpho older than v.6.1.1, or projects that have a noticeable difference in the coordinates at control points, open the Summit.smtxml project in a text editor and make sure dcn is set to 1. There is no user interface to edit this value inside Summit. Check it and edit it in a text editor such as Notepad++. Be very careful when editing the.smtxml with a text editor; do not make any change apart from the one indicated here. dcn= 0 is wrong for Inpho-originated projects Use a text editor such as Notepad++ to change the value to 1 The Summit Project Has Use Heights or Dynamic Terrain Height On in the Interior Corrections Revised July 22, 2016 Individual terrain and flying heights were added to Inpho projects in a version before v.6.1.1, but they were not exported into the Summit project until Inpho v DAT/EM added two methods to use these terrain heights in Summit in v.7.2, Use heights and Dynamic terrain height, flight height of the exterior (Dynamic Terrain). These are found in the Summit > Edit > Project (aerial project) > Interior Corrections dialog: 3

4 There was a problem with Dynamic Terrain in v.7.2 for projects in U.S. or International Feet units. The setting only worked for meters. Inpho versions to export a Summit project that has Summit s Dynamic Terrain, regardless of the units. Two things were done in newer versions: 1. Inpho v will not set Dynamic Terrain in the Summit project for projects in feet units. It will continue to set Dynamic Terrain for projects in meters. 2. Summit v.7.3 offers a new Units setting. Now any units may be converted in Summit to meters so that Dynamic Terrain will work for all projects. However, it is the user s choice to turn on Dynamic Terrain for Feet units in projects that were exported by Inpho v or higher. For Summit v.7.2 aerial project in U.S. Feet or International Feet units, select Summit > Edit > Project > Interior Corrections. If Dynamic Terrain Heights is currently set, it will not work in Summit v.7.2 due to lack of units conversion. Choose one of the other options for Summit 7.2: Choose Terrain Height only if Inpho or higher created the project, in which case meters units will be visible in the Per image heights table. Choose Use heights if Inpho v.7.1 or higher created the Summit project. Use Image Scale and project elevation is another option. Choose Use Image Scale and project elevation if Inpho 7.0.x or lower created the Summit project. For Summit v.7.3, check the setting that was exported by Applications Master. Dynamic Terrain Heights is allowed for both meters and feet as long as the units are set correctly. You must check the units! Inpho v and higher will check the units, and if they are in International or U.S. Feet, it will not set Dynamic Terrain on in the Summit project. If using Summit v.7.3 or higher with Feet units, you may optionally set the units and check on Dynamic Terrain Heights. 4

5 Atmospheric Correction Flag Mismatch No versions of Inpho lower than set the flag in the Summit project. The default in Summit is off, so when the value is not found, it is set to off. For Inpho v and higher, do nothing. It will be set correctly. For Inpho lower than v.6.1.1, open every aerial project in Applications Master, edit the project, and check whether atmospheric correction was on. Applications Master s Project Editor showing Atmospheric Correction on If the old Inpho version is not available to run, open the.prj in a text editor such as Notepad++ and look for the line, "$REFRACT_CORR_DEFAULT : on" in the first few lines: If you see that it is on, open Summit's aerial project editor, select the Interior Corrections button, and check on "Refraction Correction": 5

6 Check on Summit s aerial project Refraction Correction if it was on in the Inpho project The Inpho Camera uses Coefficients Distortion Type Summit Evolution versions 7.0 and above can read the Polynomial/Coefficients distortion type; Inpho software versions and above can write this format to a Summit project. If the Summit version is 6.8 or lower, it is not possible to use this camera distortion type. Please update. For Inpho v and higher with Summit v.7.0 and higher, you do not need to do anything. Applications Master will export the distortion method to the Summit camera. If this Coefficients type was used in the Inpho project, but the Inpho version is lower than 6.1.1, and Summit is version 7.0 or above, do the following: 1. Open the camera in Applications Master. 2. Open the exported Summit camera in Summit s Camera Editor. 3. Cut and paste the values from Applications Master into Summit s Twelve Parameter distortion type. 6

7 Inpho Coefficients distortion type Summit s equivalent Twelve Parameter distortion type 7

8 The Inpho Camera Uses Grid Correction Distortion Type No version of Inpho software exports the path and file name of any grid distortion file to the Summit project. It must always be exported separately and added to the Summit camera later. If the Inpho camera uses a grid distortion type, open/edit the camera in Applications Master and export the grid file. Open your project in Summit and open its camera file in Summit s Camera Editor. Use the Distortion tab to check on Use Correction and browse for the grid file: Browse for the Inpho grid correction file Earth Curvature Correction Code is Now Shared For Summit v.7.0 and above, Trimble shared and DAT/EM implemented the Earth Curvature correction code used in Inpho software. For more recent versions, Summit projects should match Inpho projects for the Earth Curvature Correction when the setting is on in both projects. In mismatched Inpho and DAT/EM versions, the Earth curvature correction will not match exactly, but it should still be on in DAT/EM if it is on in the Inpho project. Some correction is usually better than no correction. Note that DAT/EM s own projects using DAT/EM v.6.8 and lower and DAT/EM 7.0 and higher will not match each other s Earth Curvature Correction. How significant the difference is depends on the imagery. Update your DAT/EM software on all workstations. Do not use an older DAT/EM version to open a project that was created or saved in a newer DAT/EM version. Do not mix old and new DAT/EM versions when digitizing vectors on multiple workstations. -end- 8