Historic Documentation in 3D: A Young Professional’s First Photogrammetry Case Study – Bulgaria
Weider360 Founder Martin Weider shares lessons learned from mapping an abandoned industrial site.
Editor’s Note: At Lidar News, it has always been important to our platform to support, engage with, and help build the next generation of geospatial professionals. In this article, Martin Weider, co-founder of Weider360, shares his first photogrammetry project using a DJI Matrice 4E drone.
Written by Martin Weider. Edited by Sarah Roe
A Passion for History Meets Geospatial Technology
My passion for history was the driving force behind my journey into drone photogrammetry. There is a large, abandoned building in my city in Bulgaria that has caught my attention repeatedly over the years — somehow it has managed to avoid developers and demolition.
When my company, Weider360, acquired the DJI Matrice 4E, I saw it as the ideal subject to test our new drone and document the site in measurable, 3D detail. As a geospatial professional, I’m always seeking opportunities to apply technology in meaningful, real-world contexts.
Here is a video of the project
Overcoming Technical Challenges: The RTK Learning Curve
I’ve always wanted to create a 3D model with a drone, inspired by impressive photogrammetry projects of ancient castles. On my first day at the factory, I confidently launched the drone, following a tutorial made for this exact model. But when I hit “Start Mission,” nothing happened.
After several frustrating minutes, I noticed the Real-Time Kinematic signal was blinking red — meaning I hadn’t enabled the precise GPS data necessary for accurate mapping. This was a detail the DJI video hadn’t covered, and I’d assumed it worked automatically.
Determined, I researched RTK networks and found several claiming to offer free global coverage. I tried connecting the next day, but after waiting over half an hour for the system to converge, I realized paid access was needed. 
I reached out to drone communities and finally got a recommendation for a paid GNSS RTK service. After contacting their team, they kindly activated a free two-week trial for me.
On day three, I returned to the factory with renewed confidence. The drone quickly captured images at a speed that amazed me compared to my previous experience.
The mission was planned for over an hour, but with my only battery running low at 7% and just over halfway done, I paused the flight.
The next day, I finished the data capture. I uploaded 6,500 images for processing and let the computer work overnight. After three days, the detailed 3D model was complete — stunning, almost like high-resolution photos covering every inch of the 5,000 m² site.
When I shared the model on LinkedIn, the post received more engagement than anything I’d posted before. Perhaps it’s because the content helps people or makes them happy in some way — you tell me!
Project Objectives and Technical Workflow
The goal was to produce a high-resolution, spatially accurate 3D model that could support inspection, preservation, and potential redevelopment analysis.
The first attempt revealed the importance of RTK (Real-Time Kinematic) positioning for accurate photogrammetry. Without it, a model’s measurements cannot be relied upon. After securing access to a professional GNSS RTK network, I planned and executed a two-part automated mapping mission.
The Matrice 4E captured 6,500 images over the 5,000 m² site. The system’s rapid image acquisition and stable flight performance yielded an excellent dataset for reconstruction.
Data Processing and Deliverables
Processing the imagery took three days, producing a highly detailed, photorealistic model. The dataset supports:
- Structural condition assessment
- Distance, area, and volume measurements
- Cultural heritage documentation
- Integration into CAD, GIS, and BIM workflows
The resulting model not only met the original objectives but also demonstrated the potential of drone-based photogrammetry for diverse geospatial applications.
Reflections as an Emerging Professional
Completing this project reinforced key lessons about mission planning, data quality, and workflow efficiency. The positive engagement it received on LinkedIn suggested a broader interest in the possibilities of accessible, high-quality geospatial documentation. 
As I continue my career in geospatial technology, I see projects like this as essential learning experiences — and stepping stones to more complex, impactful work.
Please connect with me on LinkedIn: Martin Weider
Weider360 Website: weider360.com
