![]() Set up the tripod so these angles are physically achievable. We plan to do three turntable rows around the object at approximately 45, 0, and -45 degree angles. Because this is a long shoot, we use mains power for the camera and the ring light and will not rely on battery power. The camera goes on the tripod, and the filter mounts on the lens alongside the ring light. Because our subject is so small, setting up a background is easy, you do not need a large surface area. Our background will be a black piece of paper as far from the object as possible. We attached it to the rotator with some sticky clay. Because our dried poppy has a stem, we will use that as our mounting point. As anti-gravity tables are not yet a thing, we must figure out the next best thing. Ideally, the object would float in space, and we could take photos around it. This step will require the most creative thinking. For the scan, we will use a macro lens with autofocus, a ring light with polarizing film, a circular polarization filter, a tripod for the camera, a rotator, and a tripod for our subject. It is a good, easy example to test the workflow. We will make a 3D scan of a dried poppy that has a relatively uniform shape, and its texture is visible only at the macro scale. ![]() We will not introduce any new concepts in this article, only the combination. If you find an unfamiliar action or term, we highly recommend rechecking the previous articles. We will describe the process of making our example step by step without missing anything. Now it is just a matter of executing the entire process of stacking each photo for each camera position and keeping track of what is happening. Read more: 3D Asset Creation With Photogrammetry Setup Process Depending on your case, this may require a bit of DIY thinking. We must ensure good coverage of the entire object by mounting it and moving it so that there are no blind spots and the overlap is sufficient for 3D reconstruction. The final challenge is our subject orientation and camera positions. Read more: Cross Polarization Photogrammetry To combat this, we use cross-polarization lighting. Even seemingly matte objects produce specular highlights, which can mess up the algorithms and not look aesthetically pleasing. Lighting a tiny subject, whether reflective or not, is much more difficult on small scales. ![]() Read more: Focus Stacking for Photogrammetry We overcome it by using the focus stacking process, which needs multiple photos per camera position. The main challenge of 3D scanning small subjects is the thin depth of field. Thus this article will rely a lot upon a few of our previous articles. However, we are ready to take up such a task because we have covered all the basics needed in our previous blog posts. It is the most time-consuming and laborious type of photogrammetric 3D scanning. Macro photogrammetry requires combining focus stacking, cross-polarization, and 3D image capture methods to scan small objects successfully.
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