Turntable Scanning

[Carl Visagie]

Good day

I am not understanding how to generate the coded disk with CCtag to put on the Turntable.

I can see what i need on this site
https://www.archeo3d.net/?page_id=3810

But no idea on how to either get a high quality image or how to generate one using the collection of CCtag PDFs on Github.

Can someone please explain the process in a simpler fashion or provide a higher quality image?

Thank you

[Fabien Castan]

Hi,
The CCTag markers are here in PDF in high quality:

https://github.com/alicevision/CCTag/tree/develop/markersToPrint

You can print from PDF or convert the PDFs into image files using gimp/photoshop/...

[Carl Visagie]

That still does not give me a clear instruction.
What you said is similar to the how to draw an Owl meme/joke... "draw a circle here, draw another circle here, then draw the rest of the damn owl"

I understand I can put them into Photoshop. But how do you lay them out, what spacing, how does this spacing relate to the measurements in meshroom, how do you then input said measurements into meshroom, are we measuring in mm or in arbitrary units? 
Its not a case of print them out one by one and just paste them with glue in an area as you feel. Unless it is that way, but then again... how do you assign those values per mark in meshroom

[Fabien Castan]

Hi Carl,

I didn't get your question from your first email.

To use CCTag in the pipeline to scale the scene to specific coordinates, use the SfMTransform node:

And specify the CCTAG ID and the output 3D coordinates based on the way you have printed them together.

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[Fabien Castan]

Yes exactly.

The unit is your choice. If you want 1 unit in your 3D space to represent 1cm or 10 cm or 10 inch is up to your workflow and needs.

Le ven. 5 juin 2026 à 15:29, Carl Visagie <snak...@gmail.com> a écrit :

okay...

I understand that so far.

But the question is how do you determine the values... is it in points or centimeters, or meters. or is it something more arbitrary like if I make position 1 (at 12 o clock) ID 1 then I assign it a value of (X=0,Y=10,Z=0) and then that would be the basic starting point to then go next point. So in this case the next point (lets say at 3 o clock, or 90 degrees) is ID 2 and it will have a value based off of the first one set so in this case  (X=10,Y=0,Z=0... 

So if I put any more CC tags in different places I would need to calculate based on those values.

Does this sound correct?

[Carl Visagie]

okay...

I understand that so far.

But the question is how do you determine the values... is it in points or centimeters, or meters. or is it something more arbitrary like if I make position 1 (at 12 o clock) ID 1 then I assign it a value of (X=0,Y=10,Z=0) and then that would be the basic starting point to then go next point. So in this case the next point (lets say at 3 o clock, or 90 degrees) is ID 2 and it will have a value based off of the first one set so in this case  (X=10,Y=0,Z=0... 

So if I put any more CC tags in different places I would need to calculate based on those values.

Does this sound correct?

On Fri, Jun 5, 2026 at 3:20 PM Fabien Castan <fabc...@gmail.com> wrote: