Control Points - matching aerial pictures with ground pictures

[Marco Vanetti]

Hi all,
i'm writing because i haven't yet solved a problem, even if i tried with every tutorial on the web.

I took 222 pictures from the ground, with a mirrorless, and 178 pictures obtained by extratcting frames from a clip recored with the drone.
It seems that 3DF recognize two different models without matching one with the other.

I thought that CGP (from images) were supposed to be used in that case, but i can select just the images that generated the model.
Which is the right way to force the matching between this two models?

[cam3d]

Hi Marco Vanetti - GCP (ground control points) can be used to aide an alignment, but are available only in Zephyr Pro or Aerial - If you can share a link to your data with us we can look into it and advise on processing or acquisition improvement Without the data it's hard to determine what the root cause of the problem is.

[Marco Vanetti]

Thanks for your kind answer cam3d, i'm using 3DF Zephyr pro 4.5, and i resolved the problem in a way i can't find very smart...
As i read in the forum i built two different models, one with the drone's pictures and one with the mirrorless's pictures. I inserted 4 CGP with the same name in the two models, and then i imported the second one into the first one.

I mean, is possible to do that in the same .ZEP file, isnt't it?

[cam3d]

Marco Vanetti - Yes I do believe it is possible for you do guide the pictures to align in one .ZEP - I've not actually done it before myself, but here is a guide on bundle adjustment which might be helpful to you: https://www.3dflow.net/zephyr-doc/en...djustment.html

[Andrea Alessi]

Hi Marco,

that is actually the correct way to do, as at this time you cannot place control points before processing the SfM phase

An alternative is to shoot more picture that helps the automatic fusion of the two workspaces - likely, there isn't enough overlap between the two projects, hence the need to use control points (which require 2 workspaces at this time)

[Marco Vanetti]

Thanks to both of you guys,
Cam3d, thanks for your kind suggestion but that workflow need to be done with the pictures that are approved from the alignment.
As i said my main problem is to match in one step the alignment, because following this workflow i have to do this steps:

1. Aligning images
2. See how many pictures are approved (ex: 400 pictures OK /500 pictures total)
3. Calculate the model
4. Add control points
5. Launch another project
6. Aligning 100 remaining pictures
7. See how many pictures are approved v.2 (ex: 80 OK/ 100 total)
8. Add control points
9. Save and import the second project into the first one
10. Repeat until i complete the model

I think it's a very slow workflow and it's difficult to manage it.
I would like that in a future the alignement steps will be handled in one step, in one project!