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Author Topic: Marker and GCP Question  (Read 1951 times)

spiegel

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Marker and GCP Question
« on: June 11, 2017, 09:26:57 AM »
I am using PS for areal mapping with a drone (GPS in EXIF).
I am satisfied with the orthomaps (X/Y) that PS creates, even without GCPs.
But usually the altitudes(elevations (Z) are quite bad.

Normally I get the elevation of boreholes from the company which does the field work.
These elevations are good, but the easting and northing, which the company measures "by hand" is not.
So I cannot use theses values as GCPs.

Now I want to combine the "good" X-Y-values from PS with the "good" elevations of the boreholes and use the combination as GCPs.
The plan ist, to create markes at the position of the boreholes and insert the elevation manually.

Is there a way to get the easting and northing automatically (from the position of the markers in the orthomap)?
Then I only have to insert the elevations by hand, this would be comfortable. 
 

Packy_GIS

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Re: Marker and GCP Question
« Reply #1 on: June 11, 2017, 10:17:54 PM »
You have to use some sort of GIS - there you will be able to read to coordintes.

Jan

SAV

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Re: Marker and GCP Question
« Reply #2 on: June 12, 2017, 03:23:08 AM »
Hi Spiegel,

Just create markers at your borehole locations directly on the orthomap that is based on your geotagged drone imagery in Photoscan (right click > create marker). You'll see these markers appear in the reference pane on the left. I suggest you name them according to the borehole IDs. Then click on the second icon from right in the reference pane (table with a blue circle that has a white i inside) and your 'estimated coordinates' for your markers will be shown. These are the coordinates that PS estimated for your selected points/boreholes. Note that they are only as accurate as your geotagged aerial images.

You can also export these values. Simply click on the second icon from left in the reference pane (looks like a save icon with a table in the background). After you entered a filename a window will appear asking you what you want to export. Make sure that 'SAVE ESTIMATED VALUES' is checked. That's all.

You can then simply open the CSV file in EXCEL and change/replace the Z-coordinates in the table with the borehole elevations you got from the company. You won't even need to use any GIS application to this ;D
Simple solutions are the best solutions  ;)

Let me know if it worked for you.

Regards
SAV
« Last Edit: June 12, 2017, 03:27:50 AM by SAV »

spiegel

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Re: Marker and GCP Question
« Reply #3 on: June 12, 2017, 10:04:19 AM »
Hello @SAV

thank you, it works good, this will make my work more easy. 


@agisoft:
would be even more easy, if I could edit the estimated values directly in the reference pane. 

SAV

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Re: Marker and GCP Question
« Reply #4 on: June 12, 2017, 10:31:59 AM »
Hi Spiegel,

Good to hear that it worked.

Happy Photoscanning ;-)

Regards
SAV