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Adding Starnet coordinate systems

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(@squowse)
Posts: 1004
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Topic starter
 

Hoping there's a stranet expert can help me I'm trying to add the "new" Ordnance survey (UK) geoid and shift grid files.

As instructed I've put them both the files in the "Mapping" folder.

The geoid is now selectable, no problem there.

The shift grid file is a "GSB" file, downloaded from Microsurvey website. It doesn't seem to be recognised and added to the list.

I'm looking under "European systems", the existing one "OS-GPS-2002" is there. In the mapping folder the other systems seem to have MRT files. They don;t have shift grid files I suppose.

Is there a way to "compile" the files in the Mapping folder into the coordinate system list?

 
Posted : December 5, 2019 9:32 am
(@dmyhill)
Posts: 3082
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My experience is that the help desk at StarNet/Microsurvey is pretty great. I am always happy when I get off the phone/email with them.

Best service in the industry.

 
Posted : December 5, 2019 1:16 pm
Norman_Oklahoma
(@norman-oklahoma)
Posts: 7680
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I tried using the projection system you mentioned to convert a lat/long to a coordinate?ÿ and it did not work. There seems to be something wrong with that projection file.; I tried it with another projection and it did return something.

I'll second Mr. Myhill's suggestion that you call or email Microsurvey for support. They are in British Columbia, where they speak and write a dialect of the Queen's english fairly well.?ÿ

You might also have a go at entering the zone parameters as a custom zone.

 
Posted : December 5, 2019 6:26 pm
mathteacher
(@mathteacher)
Posts: 2087
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Looking at the table here, https://helpdesk.microsurvey.com/index.php?/Knowledgebase/Article/View/499 ?ÿ OS-GPS-2002 is for older systems.

Perhaps you need FieldGenius 9 or newer.

 
Posted : December 6, 2019 7:33 am
(@chris-mills)
Posts: 718
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@mathteacher

Your solution is probably correct, but the explanation is a little off. It's not a case of a different transform for older software systems. OS-GPS-2002 is OSTN02, which was the standard mapping transformation for the UK this century. The latest transformation is OSTN15 (OS-GPS-2015 in MicroSurvey). Both have transformations onto OSGB36 (which was the standard mapping projection for the UK for most of the last century. Surveys can still be produced in either 02 or 15: if they are in conjunction with OSTN02 original data then it's probably best to set the new work up the same way (engineers and architects cannot cope with transforms - or scale factors!). OSGB36 matches the vast majority of paper records based on the OS mapping, but difference between them all is not noticeable on paper maps; heights are more significant.

 
Posted : December 6, 2019 7:50 am

mathteacher
(@mathteacher)
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I see. The distance between two fixed points should be the same on either system even though the coordinates are different.?ÿ The question was interesting because it involved both the math and the implementation of the math in a computer system, so I did a bit of Googling and turned up that table.?ÿ It looked as though a later software version could handle the newer transformation while an older version might not, so I shared the finding.

Thanks for explaining.?ÿ

 
Posted : December 6, 2019 8:41 am
(@squowse)
Posts: 1004
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Topic starter
 

@mathteacher

This is in Starnet 9, not Field Genius. I have OSTN02 working, its the new shift grid OSTN15 I am struggling with.

 
Posted : December 6, 2019 12:20 pm
(@squowse)
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Topic starter
 

@norman-oklahoma

Was that the OSTN15 shift grid file? Unfortunately my Microsurvey subscription has lapsed. I wasn't too happy with the last couple of responses I got from them and couldn't justify the annual expense.

 
Posted : December 6, 2019 12:23 pm
(@squowse)
Posts: 1004
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Topic starter
 

This is the instructions which I have followed but cant get the list of coordinate systems to change even when I remove the files form the Mapping folder. I am closing and restarting, I wonder if there is some other step I need to take to get it to update the list which is stored in the "Coordsys" file

?ÿ

 
Posted : December 6, 2019 12:27 pm