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12-Photogrammetry 3D Fossils Merging Chunks Align and Quality Control of sparse cloud

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Here I want to show you how to merge the two chunks Flip and Flop, how to align them and how to check the quality of the sparse point cloud.

I am Gabriel. Jon, Charlie, Hugh, Corey and I use photogrammetry to make 3 D models of fossils. We learend how to use Agisoft Photoscan at the SVP meeting in LA in 2013.

In video 10 and 11, we have masked all the photos in both Flip and Flop. Now it is time to merge the two chunks.

Make sure one of the Chunks you want to merge is highlited.
Merge Chunks this goes fast.

Now we are ready to align the Photos. We will use Medium accuracy generic and we have to make sure that we select mask.

The alignment is done
Right click the chunk, go all the way down to Show Info ... the alignment took.

Now first, we want to check the Quality of the Sparse point cloud. Edit -- Gradual Selection -- Reproduction Error set at one ... this recent skull is too perfect for Photogrammetry. If set to error to 0.3, we can remove all the points that have a bigger error. Delete

We do not want to do this here ... go back to edit and undo.

Next we go into -- Reconstruction uncertainity this we will set at 200 ...

Now we build a dense cloud, Medium, Mild

Here is the dense cloud.

Now we build a Mesh
Arbitrary
Dense cloud
Medium ... points.

Here is the mesh

Now we build texture ... average gives sometimes more pleasing models. With mosaic a unique photo is selected and sometimes that does not look to good.

That's it for today. Have fun.

*******
Transcript:
I am Gabriel. Jon, Charlie, Hugh, Corey and I use photogrammetry to make 3 D models of fossils. We learend how to use Agisoft Photoscan at the Scociety of Vertebrate Paleontology meeting in LA in 2013. Neffra Matthews and Brent Breithaupt were organizing the Workshop.

Here we want to show you how to merge the two chunks: Flip and Flop, how to align them and how to check the quality of the sparse point cloud.

In video 10 and 11, we have masked all the photos in both Flip and Flop. Now it is time to merge the two chunks.

- Make sure that one of the Chunks you want to merge is highlited.

When you align the Photos, make sure that you check the advanced feature:
- Align all the "masked" Photos ... Adanced: constrain features by mask.
Align at a high setting: we used here:
Medium
Disabled
100,000 and 10,000

Once alignment is done:
You can check what has been done to the chunk, right clicking the chunk, go all the way down and click "Show info".

Once the first alignment has been done:
The Sparse Point cloud can be adjusted for the quality. The recent skull we have is a too perfect "fossil". Usually our fossils are deformed, flat, odd shapes ... most of them have been subjected to the pressure of around 5000 feet of sand stone and consolidated gravel ... they look deformed ... for most of the fossils we have to adjust the quality to 1 and 200:

While in Point Cloud:
Edit -- all the way down -- Gradual Selection -- Reproduction Error, set to 1 -- then press delete key.
If you do not like it: Press edit -- undo.
Then
Edit -- all the way down -- Gradual Selection -- Reconstruction uncertainyt has to be at 200.

The rest is stright forward.
Work flow ...

References:
- Agisoft PhotoScan www.agisoft.com/
- SVP Meeting 2013, LA
http://vertpaleo.org/PDFS/3a/3acc7ee9-9539-4652-b173-01dd50ced85c.pdf
Photogrammetry: Digital Data Collection in the Lab and Field:
Neffra Matthews and Brent H. Breithaupt
- Jon is our spokesperson, he has given several presentations
including at the Zzyzx Desert Symposiums in 2014, see the abstract in:
http://nsm.fullerton.edu/dsc/images/DSCdocs/2014Notadroplefttodrink.pdf

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