First time photogrammetry - Difference between OBJ and STL

Hey Folks,

yesterday i tried photogrammetry for the first time to 3d-scan a part of a tabletop miniature, using the free version of 3DF Zephyr with the 50 images limit. The pictures were taken with an iPhone 13 Pro Max on a semi-sunny cloudy day from varying angles, here is an example picture:

(Is there any way to make the pictures smaller in a reddit post?:D)

https://preview.redd.it/ubnulw8lsbfe1.jpg?width=532&format=pjpg&auto=webp&s=13fdfff08b7e17e5ccb7106e3ba1c8dbef889ac2

3df Zephyr was able to use all 50 uploaded pictures and created the following OBJ-file, which does look very good in my opinion:

https://preview.redd.it/xm5ibtszsbfe1.jpg?width=597&format=pjpg&auto=webp&s=a582f3d23ca7fbb5f2bd6d7d8192deb09489c54f

After importing the OBJ into Blender, the Mesh actually seems to look like this:

https://preview.redd.it/7n6f37i5tbfe1.jpg?width=692&format=pjpg&auto=webp&s=1e70891c0b3fc946d9989158c52b8d79c6de2626

This outcome has shocked me a bit. Does the OBJ only look this good because it uses the photos to mimic the surface while actually not being that detailled?

What can i do to improve the outcome? Am i missing something?

Thanks in advance, feel free to ask any questions. Of course i can share the complete 50-photo-set if anyone has a better solution to turn them into a sufficient STL.