Turntable Photos Not Aligning(?)

[JGaither]

Hey, guys! New to Agisoft, photogrammetry, 3D modeling...pretty much all of it. I'm primarily interested in modeling small objects on a turntable, which I already own, for 3D printing. I have lighting and a decent DSLR (Canon Rebel T3i).

I've watched some tutorials and have been screwing around trying to model some small things around my office, but I'm hitting a wall. I take well-lit photos from every angle (using the turntable for controllable, predictable incremental turns) and a camera on a tripod, for stability...and yet, I've never gotten all the photos to align and the final models are unprintable.

The image I've attached show an example of the photos I took (98 total) and what the final model looks like. As you can see "rough" is a generous description, and for some reason, the back of the model is just a hole. The torus ring at the top is a mess...you name it.

Any help anyone could give me on Agisoft settings, lighting, camera angles, etc., would be SO much appreciated.

Thanks a million in advance!

Jordan G.

[Silversound]

I haven't done turntable scans in a long time, but usually when there are align problems it's because lack of masking. if you display your camera positions, it will be very obvious if there is a major align problem.

Regarding masking, I think there is a function now that allow you to just make a mask for one image and Metashape figures out the rest of the masks. But I haven't used it myself yet, so I can't give any more tips.
/Jimmy

[Tony C]

This video may help with masking for Turn Tables and it's well worth watching the whole video but you need to look at 1:13:00. Also from you images it looks like you object is a bit refectlive which maybe causing some issues... hope it helps

[Alexey Pasumansky]

Hello Jordan,

Can you share the source dataset and the project file with us (support@agisoft.com)?

[JGaither]

Thanks for all the replies, folks! Here are some answers:

1) See attached screenshot with cameras visible; I don't know for sure, but they seem weirdly inconsistent for a tripod-and-turntable setup. Thoughts?

2) Also see other attached image for my mask, which I created and applied to the first image (as I was instructed to do). Doesn't seem to have helped, though.

3) Alex - I'm not sure how to share a "source dataset" or "project file". Do you mean the pictures I took and the Agisoft project file?


Thanks, everyone! Looking forward to nailing this down!

JG

[Silversound]

It looks like most of the photos got aligned pretty good at least. Some problems with your object I can think of is that it is one color and a bit shiny. Can confuse the align process. One thing you could try is to add a paper with a lot of details on the turntable and don't mask that part out. Just any kind of random pattern with a lot of unique details will work. I've also read about adding details to your object, like spots/stains from water color splashes with a brush.

I don't do so much photogrammetry now days, but when I do it's usually a little bigger objects that I move the camera around. I usually put masking tape around it with a lot of scribble. I rather put time into adding too much details, than realising later that I can't align my photos. It may look like I'm into some occult ceremony with a lot of spells around my sacrifice though...

[JGaither]

That's a good idea, Silversound; I'll give that a try next. Thanks!