FORAMINIFERA PHOTOGRAMMETRY: ACQUISITION OF HIGH-RESOLUTION 3D MODELS FROM SCANNING ELECTRON MICROSCOPE IMAGES

Presented here is a new method combining scanning electron microscope (SEM) images, readily-available 3D visualization software and 3D printing technology to produce useful reproductions of foraminifera tests for use in taxonomic and micropaleontological research, and for archival and educational purposes. Our unique, simple preparation method shows how to position an isolated foraminifer specimen within the SEM chamber in order to obtain a complete (360 degrees) external morphological reproduction of the foraminifera shell structure. Results from this method produce digital, high-resolution 3D models of foraminifera from SEM photographs through the use of photogrammetric algorithms. These high-resolution images can be used to produce accurately scaled 3D models of foraminifera. Currently, digital imaging of microfossils to produce a 3D digital model requires expensive and time-consuming micro-Computer Tomograph (micro-CT) technology. Here, the non-destructive, removable fixing of foraminifera for SEM measurement is a comparable procedure for external morphological examination. This modeling method is most suitable for the study of foraminifera since the best and more cost-effective high resolution images are generated using widely available non-destructive SEM imaging. With relatively minor adaptations to the mounting of the specimens, readily available software, and careful capture of images almost any SEM can produce a digital 3D representation of the specimen. These digital foraminifera renders are easily shareable as digital files and allow generation of large numbers of scalable, printable 3D digital models that would be available for education, archiving and taxonomic research.