RTI – accuracy tests


To test the absolute accuracy of the RTI files under controlled conditions, I constructed a virtual environment in Blender, eliminating all possible external error sources.

To read more about my approach and the results, click here.

RTI – alternative visualization


Using the maximum lighting value for each pixel across all images in combination with the normal map visualization from CHI’s RTIViewer, a static composite image that incorporates both surface topography and color information can be produced using regular image manipulation software.

For a detailed description, further examples and comparisons click here.




Duration: Jan 2015 – Dec 2015



Gohar Tepe

The Gohar Tepe-Project has been initiated in 2003 by the Cultural Heritage Organisation of Mazandaran. In 2009, the project was reinstated as a colaborative endeavour with the University of Munich, Germany. The project has unearthed evidence for activity from the Chalcolithic up until the Iron Age periods, during wich the site has served different purposes. Gohar Tepe constitutes the largest archeological site in the Mazandaran Region of northern Iran.

As a participant of the 2012 Summer campaign, I was tasked with documentation of finds from the current and former excavations, using classical photography techniques and Reflectance Transformation Imaging (RTI).

Franco-German Figurines Project (FGFP)

Duration: ongoing

The Franco-German Figurines Project (FGFP) is financially supported by the Universities of Strasbourg (France) and Wuerzburg (Germany). Its goal is primarily the recording of the Iron Age female terracotta figurines found in Transjordan and the creation of a refined typology of these objects.

Between spring 2012 and summer 2014, the project team consisting of Regine Hunziker-Rodewald, Astrid Nunn and myself carried out five preparative and seven research stays in France, Germany, and Jordan, as well as in the United-States and Canada. The team exclusively works on material kept in museums, in storage facilities and in university collections. To date 423 female terracotta figurines, 96% of them fragments, have been registered.

Reflectance Transformation Imaging (RTI) produces dense surface data of captured objects, by far surpassing traditional photography in the versatility of its output format.
In my function as the head of documentation, I have recorded 229 figurines from collections in the US, Canada and Jordan using the RTI highlight method. I was also given the opportunity to hold lectures on this subject in the US, France and Germany.

Check out the following pages for more information on RTI:
Selected examples from the FGFP
Accuracy analysis
Alternative visualistion approaches
Quality enhancement experiments
Automation concepts