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x, y, z to lat, long and elevation?

Hello
I use non georeferenced IGN aerial photos to make models. I am trying to georeference the model using 3DGCP import of reference point in latitude, longitude and elevation.
My problem is that the import of these new manual points needs x, y, z and not lat., Long, and elevation …
How to solve this problem?
thank you in advance

Hello,

You need to change the coordinate system of the GCPs to WGS84:

Yes! Thank you

Hello Christina

For Phantom 4 RTK flight without GCPs,

Do we need to choose WGS84 as well? Or projection datum WGS 84 / UTM zone 56S?

I processed 400 jpg images from Phantom 4 RTK, and found that the non-vegetation area has good orthomosaic image while dense tree canopy area brings blurred and twisted orthomosaic. I am wondering whether the result is relevant to the GCP/MTP coordinate systems.

Looking forward to your suggestions.

BTW, my Pix4D has not updated to the most recent version yet.

Thanks.

Cindy

Hi Cindy,
please find here a detailed post about how to process DJI Phantom 4 RTK datasets with Pix4D

here you can find more information about How to improve the outputs of dense vegetation areas?
I hope it helps :slight_smile:

Thanks. Christina.

We flied Phantom 4 RTK and obtained RGB images whose coordinate system is recognized by Pix4D as WGS84 / UTM Zone 56S (we are in NSW of Australia); The coordinate system of GCPs collected by our surveyor is MGA2020 (I think it is GDA2020, the new Geocentric Datum of Australia), zone 56s, Height is on AHD71.

I had a look at the list of coordinate systems of GCPs at Pix4D (my Pix4D version is 4.4.12), and found GDA (Geocentric Datum of Australia)1994 but did not see GDA2020.

Just wondering if I can import the GCPs with that specific coordinate system, and ensure they are compatible with the coordinate system of images at Pix4D for processing.

If not, how can I do to make them compatible?

Your help is much appreciated :slight_smile:

BTW, not sure whether version 4.5.6 of Pix4D includes GDA2020 in the list of GCPs coordinate systems. If not, it would be helpful to include GDA2020 since a lot of Australian organisations are planning to or already have changed to GDA2020 from GDA1994.

Hi Cindy,

We are aware of the coordinate system change and you can test our preview Pix4Dmapper 4.6.1 which contains the GDA2020 coordinate system! Note that there currently a small bug that does not allow you to search for the coordinate system by name. Instead, choose the right coordinate system “From List” or “From EPSG” in Advanced Coordinate Options.

However, note that Pix4Dmapper does not support local vertical coordinate systems. You can find more information about that here: How to define Pix4D outputs with respect to a Geoid model.

Additionally, as mentioned by my colleagues Christina, blurry area in the orthomosaic are caused by image content that is difficult for photogrammetry. You will find the info you need about how to plan your future flights above vegetation and processing the data in How to improve the outputs of dense vegetation areas?.

I hope this helps! :slight_smile: