Georeferencing the Past: Precise Meydenbauer Camera Position Recovery using Imagery from the Freyburg (Unstrut) Church Campaign

Duration: 6 months
Completion: November 2025
Supervisor & Examiner: Dr.-Ing. Michael Cramer

Historical photographs are valuable spatial records but are often difficult to georeference due to missing calibration data.
This thesis investigates precise camera position recovery from single archival images taken during Albrecht Meydenbauer’s Freyburg (Unstrut) church campaign.
Single-image orientation methods are combined with national surface models to assess feasibility and limitations.

Albrecht Meydenbauer was a pioneer of architectural photogrammetry.
Recovering the original camera viewpoints of his historical photographs enables their integration into modern spatial reference systems and supports quantitative analysis of architectural change.

Camera positions were estimated using DLT, classical spatial resection, and PnP-based methods with unknown focal length.
National image-based surface models (bDOM20), an independent close-range photogrammetric model acquired with a Nikon D800E and a LiDAR model were used for validation.

The reconstructed camera positions form a coherent spatial arrangement around the church.
PnP-based methods proved more stable than classical spatial resection.
Large positional deviations in SRS solutions were linked to near-planar point configurations.

The study demonstrates that meaningful camera position recovery from historical single images is feasible despite incomplete camera information.