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Why is the camera upside down from the images?

I just started using Pix4D recently. 

One of my colleagues taught me how to create a project and process it.

The camera which is a on the project I created seemed to be upside down (if impossible) when compared with my other works.

Any advice or solution will be very much apprec

iated.

 

Hi Samantha, 

Thanks for describing the issue and for posting screenshots.

In your screenshot it seems as if there are no coordinates assigned to the images, but that the coordinate system of the images is set to WGS 84/UTM zone 30N: 


This explains why there are only green and no blue camera icons in the second screenshot, as only the optimized positions are displayed (all initial positions being at (0,0,0)). I think this explains why the end up reversed, as there is no reference which can be used to correctly orient the project. 

If you have the image coordinates adding them should solve the issue. If you do not have them, I would modify the image coordinate system (and output coordinate system) to “Arbitrary” and then add an orientation constraint to the project if it is still reversed. 

Here are articles that should be helpful: 

Keep us posted if you can fix the project or need further help. :slight_smile:

After modifying the image coordinate system, can I manually add tie points in to georeference it since I got ground control points established on the site? 

Sure, I would recommend to follow Method B in this article: 
https://support.pix4d.com/hc/en-us/articles/202560239#label2

I copy the content for convenience: 

Instructions

1. Obtain GCPs measurements in the field or through other sources: 202557489
2. On the Menu bar, click  View   ** Processing .  **The Processing bar appears at the bottom of the Main Window.
3. Select _1. Initial Processing _and deselect _2. Point Cloud and Mesh _and 3. DSM, Orthomosaic and Index.
4. Click  Start.

  1. Add / import and mark  ONLY ** 3 **of the GCPs in the rayCloud202560109.
  2. After having imported the  GCPs and having reoptimized the reconstruction, add / import the remaining GCPs with the GCP /MTP Manager  WITHOUT  marking them: 202560039.
  3. Mark the GCPs in the rayCloud: 202560769.
  4. Click Process > Reoptimize.
    9. (optional) Regenerate the Quality Report by clicking  Process > Generate Quality Report.