Topics

1

General / Changed pitch and markers error in meters increased

« on: December 08, 2022, 03:54:57 PM »

Hi, I had to change the pitch of my model. When I did it, the Markers error (m) increased from 0.00Xm to 4-25 m. Is there a way to automatically correct the marker's error without setting each market individually?

I have hundreds of markers.

2

General / Wrong orientation after alignment

« on: August 24, 2021, 04:16:43 PM »

Hi everyone,

I have aligned about 244 images that have considerable overlap. I upload the external reference for each image. However, the point cloud default frontal view (xyz) shows the model from one side, not the frontal view. When I align the same images without coordinates, Metashape seems to do better work.

I have used the Lat long coordinates in decimal degrees WGS84 and run the alignment.  I have also transformed it to UTM. However, the final result is the same.

I have modified the default accuracy to the accuracy of the "GPS" used (see image attached). Because the structure modelled has a steep slope, I have tried pitch 0 and pith 90, but it did not improve the orientation of the point cloud. 

I attach the reports of the models with different in ( GCS WGS84, UTM N25, no coordinates, screenshot). Hence, you may be able to see what is wrong and how can I fix it.

I am looking forward to getting advice from the Agisoft Metashape experts.

Thank you,

Lia

3

General / Fragmented reconstruction (underwater)

« on: August 16, 2021, 05:34:23 PM »

Hi everyone,

I will appreciate the answer of one of the experts of Agisoft Metashape Pro.

I am sending a detailed explanation that includes the screenshots of the problem briefly described here. I believe it is essential to understand what I refer to.

Description:
The following reconstruction corresponds to an underwater feature video recorded by ROV (28 frames per second). One frame per second was extracted to use in this reconstruction.
Number of frames (images): 592
In the 10 mins video, 26 USBL (Ultra short baseline) positioning was recorded. The USBL positioning was upload in R to obtain positioning per second of each frame grab extracted (1per sec) and exported as CSV. This CSV was used in Agisoft Metashape Professional (64bit) to reference the images.

Problem: when aligning the images, I get the message some images failed to align. And the alienation jumps spaces within the reconstruction. like if the video was not continuous, but it was. (Fig 1)

Questions:

Why is the reconstruction fragmented while the video where the images come from is continuous?
Why are the small chunks of images upside down?
Why are some cameras only used in the reconstruction when I used the reference, not when I aligned without a reference?

4

General / Vertical structure orientation, external reference

« on: July 06, 2021, 04:14:27 PM »

Hi,

I am working with a set of images extracted from a video transect along a underwater vertical wall from recorded from the bottom to the top.
The georeferenced positions  of each image were extracted from an external device (USBL). It is relatively accurate and my point and dense cloud are fine.

But the xyz orientation is incorrect. How can adjust the settings to  account for the forward facing setup of the camera (as opposed to the assumed downward facing camera used in aerial photography).

A published papers mentioned that they add a pitch of 90 degrees (However, they used Agisoft PhotoScan  no A Metashape). The only way I found to add pitch was on the imported reference option. So I add a column in the reference table called pitch  with values of 90 per each row. For instance the reference table added had longitude latitude attitude( in my case depth) and the extra column called pitch.

Agisoft Metashape imported all the values for my coordinates but not pitch and the model of the wall shows a horizontal orientation instead of the actual vertical one. What should I do to get XYZ orientation corrected?

Thank you for your time and help.