Remembering Dr. Ernst Rohner, Datacolor

Ernst Rohner was a pioneer in the science of colorimetry and a key figure in the history of Datacolor. A creative, collaborative, and influential colleague, Dr. Rohner passed away on January 25, 2018 at the age of 91.


Dr. Rohner received his doctoral degree in 1956 from ETH (Eidgenössischen Technischen Hochschule) in Zurich, under Prof. Dr. M. J. O. Strutt. His doctoral dissertation was “Ein automatischer Filterspektrograph.”


Scientist and colleague
His curious and collegial nature led Dr. Rohner to spend hours discussing matters of interest with his peers. As a result of one such discussion, Dr. Rohner and Danny Rich, formerly a principal scientist at Datacolor and now a senior color physicist at Sun Chemical, wrote DCI95 color standards that focused on a color difference formula that allows channel dependence on the product being examined.


Dr. Klaus Witt of BAM (the German Federal Institute of Materials Research and Testing) helped Rohner and Rich prepare their work for publication, and noticed a potential simplification. He proposed the improved model to the German Institute for Standardization (DIN), and the standard evolved into DIN99.


Dr. Rohner’s impact on the industry and on Datacolor can’t be overstated. He was the technical mastermind behind the company’s MatchTextile color management technology, and contributed to milestones such as these:



  • Color Formulation System DATACOLOR 7100 – the leading system in the European Textile Industry during this decade


  • DC3880 with Monochromator MC83 –first 16 channel diode array sensor built diode by diode in Dietlikon
  • OSIRIS – comprehensive software package for textile industry color formulation
  • Datacolor Tolerancing Model
  • DC3890 and PIGMENTA for non-textile applications
  • Elrepho 2000 – Designed following an intensive market study of paper customers and referring institutes


  • Development of the high-resolution MC90 sensor in collaboration with CSEM in Switzerland. This monochromator was used more than a decade in all DC instruments, and today’s SP2000 is still based on that technology.


One former colleague, Walter Franz, still remembers the passion with which Dr. Rohner described colorimetry at a Hohensteiner Institute seminar in the 1970s, and how he taught the relatively new technology in an understandable way. Generous with his broad knowledge and experience, Dr. Rohner also served on many industry committees.


Datacolor founder
In the late 1960s, Ernst Rohner founded Datacolor with partners, to apply color systems in industry – blending computerization with precise color instruments. Around the same time in the U.S., a similar company, Applied Color Systems, was being formed. These two companies eventually merged and resulted in today’s Datacolor:


Dr. Rohner’s personal influence, in addition to his business and technical contributions, is considerable. Walter Franz describes him as the most important personality of his entire business life. He taught not only colorimetry, but how to treat customers and competitors with unfailing respect and fairness. He shepherded hardware and software to market, and taught the team not to sell purely base on prices but through our product knowledge and the knowledge of our customers’ applications. And no matter how hard he worked, he enjoyed stimulating conversation, good wine, and his pipe.


Always questioning, learning, and sharing, Ernst Rohner continued to visit colleagues even later in life, when he lived in a retirement home across the street from Datacolor’s Dietlikon, Switzerland office.