3D Reconstruction and Digital Preservation of Mandaluyong City’s San Felipe Neri Parish Interior Using Close-Range Photogrammetry

Abstract. This study investigates the application of close-range photogrammetry for digital preservation of cultural heritage, focusing on the interior of San Felipe Neri Parish in Brgy. Poblacion, Mandaluyong City, Philippines. The main objective is to generate a detailed and accurate 3D reconstruction of the church's interior and associated features to showcase modern heritage preservation efforts. The study is oriented towards the 11th Sustainable Development Goal of the United Nations: Sustainable Cities and Communities. In particular, it addresses target 11.4–Strengthen efforts to protect and safeguard the world’s cultural and natural heritage. A modified workflow from Bedford’s (2017) Photogrammetric Applications for Cultural Heritage was implemented, using an iPhone 11 camera, measuring tape, Agisoft Metashape, and MeshLab. A total of 219 images were acquired and processed, and the resulting model was rescaled using field measurements. The final model achieved less than 5% error across all key object measurements, validating the accuracy and potential of accessible photogrammetric tools in indoor heritage documentation. Several challenges were noted, such as mesh distortion from moving objects (e.g., cloth), texture distortion from excessive lighting, and incomplete reconstruction of single-color surfaces (e.g., rugs, screens). Despite these issues, the study demonstrates that low-cost, consumer-grade equipment combined with an optimized workflow can produce reliable 3D models suitable for documentation, visualization, and conservation planning.