georeference the images

[thomask]

Hello 

I have photographed an object with targets. The images were created in a local coordinate system. The targets were measured with a total station. Now I aligned the images (Align Photos) and searched for the target marks (Detect Markers). Then I imported the TXT file with the coordinates.
Now the targets have MGI coordinates and the camera images have none.
How can I georeference the images and in which Workflow step should I do that?
The goal is to create a georeferenced 3D model (MGI34 System).

[Alexey Pasumansky]

Hello thomask,

You should have selected proper coordinate system in the Import CSV dialog, if you were loading the coordinates from the text file.

Nevertheless, if you haven't used Optimize Cameras option after loading the coordinate system, you should just go to Reference pane settings dialog and select proper coordinate system from the list. Then press Update button on the Reference pane toolbar.

[thomask]

Alexey Pasumansky

Thanks for your answer. It worked. The images now have coordinates. The co-ordinate system is the same as the target points.

After I create the dense point cloud, I would like to filter the point cloud. I have duplicated the point cloud and would like to filter the point cloud (copied version) using "Filter Dense Cloud...". The predefined value is "0.001090830 m". Which value should I choose? I've never done this before.
Thanks for your answer.

Translated with www.DeepL.com/Translator (free version)

[Alexey Pasumansky]

Hello thomask,

Filter dense cloud command should be used to reduce the point density. The input value should correspond to the desired point density, the default value corresponds to the average density of the current dense point cloud.

[thomask]

Hello, Alexey Pasumansky,

Can you please help me with this problem I have photographed an object with 2 lenses (24mm and 50mm).
-- in the first chunk, the pictures with the lens are 24mm. Have performed the workflow Align photos, Camera calibration new, Detected AGISOFT marker (load txt with the marker coordinates), Build Dense Cloud, Build Mesh.  Export Model.Chunk 1 is georeferenced (coordinate system EPSG 31253), because I measured the markers terrestrially.
-- In the second chunk the images (lens 50mm) are without markers (=local coordinates). Workflow: Align Photos, camera calibration new.
-- Then I activate chunk one and do the workflow Align Chunks... (Method: Point based; Accuracy: Highest) .
-- Problem: The images from Chunk 2 should be textured to the model of Chunk 1 (Method: Point based) and be in the EPSG 31253 coordinate system.

Final result: Create a georeferenced model with images (low resolution 24mm lens) and texture it with images (high resolution 50mm).
Is that possible?

[Alexey Pasumansky]

Hello thomask,

Have you tried to run the Align Photos operation for both sub-sets (24 and 50 mm) in the single chunk at once?

If it works, then after alignment you can disable the 50 mm images and generate the dense cloud, mesh or DEM, after that disable 24 mm images, enable 50 mm images and generate the texture or orthomosaic.
The georeferencing using the markers can be completed after the initial alignment is finished.

[thomask]

Hello
I did not try to load all images (24mm and 50mm) into a single chunk and align them.

For my master thesis I have to create two georeferenced point clouds of one object.
-- first point cloud by a laser scan --> load the point cloud --> build mesh in Agisoft.
--second point cloud by images (24mm lens). Align photos, camera calibration New --> Build dense cloud --> Build Mesh in Agisoft.

Export of the two models

With a better lens (50mm or 75mm) images of the object are taken for damage analysis. These images should then be textured to Model 1 and 2.

So it is better if I only have pictures of the 24mm lens in chunk 1 to create the georeferenced model and in the other chunk 2 the pictures (local coordinate system) I need for texturing.

Can I texture images from Chunk 2 to a laser scan point cloud, model?

Thanks