foster+freeman may be now known worldwide for its crime-lites or VSC instruments; however, back in 1978, Doug Foster and Bob Freeman came together for a research project where they developed foster+freeman’s first and most popular instrument. Such is the level of success achieved by the foster+freeman ESDA, the terms ESDA and ‘the ESDA process’ have become industry standard terminology for revealing indentations or impressions on paper.

The ESDA started as part of a research project to develop a non-chemical, non-destructive method of identifying fingerprints on fabric. While the project itself did not prove successful, the ESDA’s secondary use of detecting indented writing on paper proved to be of huge interest to document examiners worldwide.

With strong backing from the UK Home Office, Doug Foster and Bob Freeman formed a partnership and made the first run of ESDA devices from the garage at Doug’s home.

Following the success of the ESDA, foster+freeman set out building on their existing knowledge base of questioned document examination and looked at developing a workstation that would be far more advanced and complex. This workstation would enable examiners to perform infrared examinations of documents for the ‘rapid exposure of concealed information and assessment of authenticity’. This workstation would become the VSC-1 of the Video Spectral Comparator. Unlike any existing forensic instrument, the VSC used a highly sensitive camera to display variations in IR absorption and fluorescence on-screen, allowing examiners to make real-time adjustments to boost clarity and contrast. By 1990, the Video Spectral Comparator could be considered to be a global success, with over 400 VSC instruments having been sold in more than 45 countries.