Using markers for turntable photogrammetry and adding scale to 3D models in Agisoft Metashape Pro

[@chlbrn]

Thanks man, your tutorials on photogrammetry are the best among the tutorials on youtube. I am serious.

[@gabrieladarocha.digital]

Thank you, Alex. What a great tutorial, specially because I couldn't follow correctly the instructions on Metashape page and follow your steps was much easier for me. Cheers!

[@KILLAHUNT1]

Your videos are so well done and informative, can you make one of your method of photo capture for turntable photogrammetry

[@alexelvisbadillo]

I may film some of the process this summer. Stay tuned!

[@danielkotzer636]

If I want to scan an object in 4 chunks, top, bottom, left, right, do I need 4 marker palets? you can't use the same marker palet for 2 different chunk?

[@alexelvisbadillo]

You can reuse the palettes for different chunks, but make sure that when it comes to aligning chunks you delete the markers from the chunks that have repeated markers. Particularly if you use the marker based alignment method.

[@danielkotzer636]

@@alexelvisbadillo markers helps Metashape align the photos properly, so once the photos in a chunk are aligned, i should delete the markers before merging the chunks together? The marks are not needed for merging and aligning the chunks together?

[@alexelvisbadillo]

Correct. If you are doing a marker based alignment then the duplicate markers in two different chunks will mess up the alignment. Picking unique points on multiple chunks that are named the same will then be used for alignment of chunks. If it's a point based alignment, be sure to adjust the region to only the model and maybe do some masking.

[@danielkotzer636]

@@alexelvisbadillo if I want to create 2 more marker pallets myself, one for right side and one for left side, can you do a video showing how it can be done? Or maybe you already made one?

[@Ben-vq3nm]

Is it possible to add a scale to an orthomosaic photo (visible on the exported jpeg for reference length)? that would be super awesome if you have any tips on that.

[@danielkotzer636]

Another question: if Metashape is aligning all photos, even without markers, is it still better to use markers because the alignment is more accurate with markers?

[@anttiv7109]

when assigning a scale to a model, is there a way to resize the model according to the measurements or do I need to do it in a 3d-modeling software such as blender.

[@byunjoy1320]

Good tutorial for agisoft scalling!However I got a problem with merge with markers,it seems agisoft only rotate and scale chunks to match each other (the alignment is so quick i wonder if its working with tile points), it work quite differently compares to Realitycapture which it can use hand place control point to help with the alignment. How can make similar action with agisoft.

[@alexelvisbadillo]

Are you using the marker palettes? If so, you may need to change the names of the markers for one of your chunks so that they don't have the same name as the other chunk. Otherwise the markers on the palettes with just align. Also, here is a video on marker-based alignment. kzbin.info/www/bejne/jquVaHx3Yqd2maM

[@toastedmangoflight]

Hello! Thanks for sharing this tutorial and sharing the markers. Is there a bigger size marker for photoscanning bigger objects like the size of a car? Thanks for any help..

[@alexelvisbadillo]

I got these markers directly from Agisoft Metashape. If you go to Tools-->Markers, you will see Print markers. You can make these bigger for larger projects.

[@toastedmangoflight]

@@alexelvisbadillo Thank you!

[@samiketola306]

Hi. Thank you for the tutorial. How would you mask the turntable and the background after this and merge the chunks? For what I know, the masking from image should be done before the alignment.

[@alexelvisbadillo]

Glad you enjoyed the video! Check out one of my other videos about masking. There, I show how to do it.

[@samiketola306]

I have seen them. But I still don't understand that if you have to start with masking, before alignment and you mask the plate and markers away, how do you scale the model after that? Or if you scale the model first you have to align the photos before that. And if the photos are aligned, you can't apply the masks after alignment

[@alexelvisbadillo]

@@samiketola306 if you set up a monochrome background, you can mask photos first, and then detect markers and align. The turntable will stay so that you can align the photos. Then, after you align and finish both chunks, you can do a marker based alignment. At that point you can either crip out the unwanted points that make up the turntable from the dense clouds of either chunk and then merge chunks and mesh. Or merge chunks first, and then run a mesh from depth maps on the new chunk. The tables will cut themselves away.

[@samiketola306]

Thank you so much! This is the advice I have been searching for days. I will try it first thing tomorrow!

[@davidluzar3417]

I messed up and printed your markers on A4 paper. Is there any chance to get the correct distances between markers if they were printed on A4?

[@alexelvisbadillo]

If it was printed at 100% then they should be correct, but the entire marker palette will not print. Otherwise, it is likely the marker palette was reduced in size. I would double check your distances with a ruler.

[@heavyweather]

Any idea on putting markers on an object suspended from the ceiling and spinning?

[@yo3hi446]

Nice job

[@georgeluna6217]

The thing no one explains is how you choose what type of marker you have to use?? There different tags out there..Any one know why to choose circular or not April Tag for eg?

[@lucasdosanjos2810]

i added some markers, but when i click on the flag to see them, they just don't appear on the map, can someone help me?

[@alexelvisbadillo]

Any luck?

[@lucasdosanjos2810]

@@alexelvisbadillo yep, I just change my software to an oldest version, and then everything works pretty well :)

[@lalljp]

Here's what I don't understand and no one seems to be explaining... How do you tell Agisoft that the markers are on the turntable? I'm digitizing large old and fragile maps with a lot of 3D features due to age but the table needs to be recognized as a flat surface and the XY plane. You didn't do anything to make that happen, it just did. But why? What made the software understand that the markers are "the ground"?

[@alexelvisbadillo]

From what I understand, Agisoft simply detects these types of markers. I downloaded them from the program itself and then made the marker palettes. Then I run detect markers and it can identify that specific pattern, place a point in the center, and then assign a unique ID # based on the pattern itself.

[@Bala92635]

Not Detecting My Markers. please tell me what would be the reason

[@alexelvisbadillo]

Without more context, it's hard to know exactly what may be causing this issue. If I had to guess, it may be an issue of depth of field. Check all the images and make sure that the markers are clear and not blurry. If they are blurry, you may need to adjust the aperture (f/). But in all honesty, without knowing anything about your photocapture environment, it is difficult to know. It could be one of many different factors.

[@Bala92635]

@@alexelvisbadillo thank you very much sir

[@chuckkuan4728]

what's the difference between palette 1 & 2? haha sorry if i missed this from the vid.

[@alexelvisbadillo]

It's a different set of numbers. You use one for one half of the object, then change the palette to the other for the other half of the object. This will help when aligning chunks. Otherwise, if you forget to swap out the palettes you may run into issues when doing a marker based alignment.

[@chuckkuan4728]

@@alexelvisbadillo ooh! thank you. can't wait to get nice scans of all sorts of random things!!

[@chuckkuan4728]

@@alexelvisbadillo ...just realized that you explained the reasoning in the video! thanks again.