GEOMETRIC CALIBRATION OF THE HASSELBLAD H3D 
MEDIUM FORMAT CAMERA 
A. Fauner, R. Ladstadter *, V. Kaufmann 
Institute of Remote Sensing and Photogrammetry, Graz University of Technology, Austria 
KEY WORDS: Photogrammetry, Digital, Camera, Calibration, Close Range, Aerial 
ABSTRACT: 
The Hasselblad H3D digital camera, which is designed for professional studio shootings, is equipped with a 39 megapixel digital 
back. It would be desirable to use this very high geometric resolution in photogrammetric applications. Unfortunately, the digital 
back does not have a tight connection to the camera body. In addition, the unknown internal image processing algorithms and the 
autofocus lens make it difficult to obtain a reliable camera calibration. In this paper, we investigate whether the Hasselblad H3D 
camera can be calibrated for use in photogrammetric applications. Repeated calibrations were performed using a 2D (planar) target 
as well as a 3D test field. Results of the individual calibration projects are compared in order to analyze the stability of the camera 
over time. We also investigate if there is a fixed pattern of systematic image residuals (after removal of radial distortion), which 
could be described by a distortion grid. Software tools were developed for semi-automatic calibration using the MATLAB 
programming environment. This calibration software consists of a graphical user interface supporting automated and precise 
measurement of circular point targets, robust calculation of initial orientation parameters and bundle adjustment with self-calibration 
capabilities. The commercial software package PhotoModeler (Eos Systems Inc./Vancouver) was also used for comparison to derive 
calibration parameters based on the planar target. 
1. INTRODUCTION 
In this paper we present repeated geometric calibrations of a 
Hasselblad H3D digital SLR camera (see Fig. 1). The H3D 
digital back holds a 39 megapixel image sensor (36.7 x 49 mm) 
and can be detached from the camera body for maintenance. 
Our equipment includes three HC lenses, i.e., 3.5/35 mm, 
3.5/50 mm, and 2.8/80 mm. Image data can be stored on 
internal CF cards (type II) or on external storage media 
(Imagebank or computer). Image data (16 bit, color) is stored in 
lossless compressed Hasselblad 3F RAW file format. Automatic 
autofocus must be switched off for photogrammetric work. The 
internal tilt sensor must also be disabled for proper 
photogrammetric image orientation. Hasselblad FlexColor 
software (version 4.6.7) is needed for further image processing. 
Digital correction of the (lateral) effect of color aberration is 
carried out by “Digital APO Correction” (DAC). 
Figure 1. Hasselblad H3D with fixing bar applied 
Raw image data was converted to RGB 8 bit TIFF for further 
photogrammetric processing. The final image size was 5412 x 
7216 (file size of 111 MB for uncompressed storage). 
The H3D has been successfully used in terrestrial 
photogrammetric projects, e.g. for glacier monitoring and 
architectural projects, and in helicopter based mapping projects 
(Raggam et al., 2007). A relative accuracy of point positioning 
of at least 1:10000 is needed for such applications. A reliable 
camera calibration must thus be performed for all three 
available lenses. Furthermore, we wanted to investigate the 
stability of the H3D camera by comparing repeated calibrations 
(in total four calibrations during 9 months). 
In order to derive calibration parameters from images taken of 
2D or 3D targets in reasonable time, it was necessary to 
implement a (semi-)automatic workflow for point measurement, 
calculation of approximate exterior orientation (EO) parameters 
and final bundle adjustment. This was done in a master thesis 
(Fauner, 2008) and a bachelor thesis (Langauer, 2008). Results 
were cross checked by the commercial PhotoModeler software 
package of Eos Systems Inc. (PhotoModeler, 2008). 
Another aim of this study was to evaluate the quality of 
calibration results using a low cost planar (2D) target and to 
compare it with the results from a 3D test field. Special 
investigations were carried out to evaluate systematic image 
errors caused by the eccentricity error of the ellipse operator 
and distance dependant lens distortion. 
Corresponding author.