foster+freeman BLOG
VSC: The premier range of QDE workstations
Today, the VSC has become the premier range for QDE workstations; it is the most innovative and precise tool to unravel mysteries hidden within documents, artefacts, and even passports. We delve into the rich history, technological intricacies, diverse applications, and profound impact of the VSC. From its pivotal role in forensic investigations, where it uncovers hidden details crucial for authenticity and fraud prevention, to its contributions in art conservation, where it unveils secrets hidden within historical artefacts, the VSC stands as a beacon of innovation, reliability, and precision in the realm of forensic technology. Join us as we journey through the evolution and significance of foster+freeman’s premier range of QDE workstations: the Video Spectral Comparator.
History
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.
The first models of the VSC had a limited spectral range, usually just UV and IR, with basic imaging capabilities. However, today’s versions of the VSC now include high-resolution 12MP cameras. Super-resolution imaging up to 127 MP and 15 modes of advanced UV-Vis-IR imaging. The first VSC to have its dedicated software package and be considered digital was introduced in 1985 with basic but for the time advanced questioned document capabilities. In comparison, today’s VSCs come with the latest and greatest in custom-built software packages. The VSC SUITE software maximises the effectiveness of document examinations by giving the user control of all VSC functions via a fluent, quick-access toolbar.
One of the main working mechanisms of the VSC is how a human eye perceives colour; when the eye sees a different colour, it perceives a different wavelength of light. It also uses the electromagnetic spectrum; the VSC does not just use the visible spectrum of light that a human eye can see. It employs the use of the electromagnetic spectrum, which includes UV and infrared light sources.
How Does it work?
The VSC works on the principle of light and electromagnetic radiation. The principle states that, generally, when light hits a surface, multiple interactions between the light and the object result in different emitted wavelengths. The types of interactions are defined as the following.
Reflection: this is where the object reflects all or most of the light. Absorption: where the item absorbs all or most of the light. Reflection and absorption where a combination of both occur. Transmission, where light passes through an object, and finally, luminescence, light is absorbed and then re-emitted.
The VSC works on the perception of colours; we see different light wavelengths when we see a different colour. As some details we seek in questioned document examination are often hidden and non-visible, we have to access non-visible areas of the light spectrum. We achieve this with the VSC by using multi-spectral illumination; this is achieved with full LED illumination picked for wavelength accuracy.
When we expose a document to a wavelength of light, particularly the non-visible wavelengths ultraviolet (200nm-400nm) and infrared (700nm – 1000nm), any light that is reflected we would not be able to visualise without the use of special filters to isolate these wavelengths. These filters are such as Bandpass filters (400-700nm), long pass filters (>700nm), short pass filters (<400nm), polarizing filters, neutral density filters and IR/UV filters.
The VSC uses multiple illumination methods to find a document’s hidden details. Some features, like ridges or indentations, are not visible when lit from a spot or flood light, but we can visualize the indentation when using oblique lighting. The VSC uses spot, flood, oblique, and transmitted lighting to detect more evidence.
Applications
What are the use cases for the VSC?
The VSC is a highly versatile machine; it was first developed and made to advance the ESDA process. Originally it was just thought to be for the forensic level examination of documents; however, in the 40 years since the first VSC was made, the world of questioned documents has changed drastically, and so has the technology of the VSC. With thousands of machines used daily worldwide, the VSC is employed in several scenarios. With the modern VSC using the latest and greatest technology in terms of camera, light sources, software and imaging capabilities, it is no surprise that the VSC is used for a wide range of applications, not just questioned documents.
Forensic Examination of Documents
VSCs are now the most advanced QDE workstations worldwide; the VSC combines sophisticated digital imaging and multi-wavelength illumination technology with a clear and efficient software interface to provide a complete solution to examining all questioned documents.
The VSC can perform a multi-spectral illumination examination of a questioned document to reveal its hidden details and uncover the evidence. It can see through the layers of a document to reveal how it was tampered with. It can differentiate between original and copied signatures and writing.
The VSC is often used to examine documents for ink analysis; different inks fluoresce under varied light conditions based on their properties. Even inks from the same source have different properties; we can use the VSC workstations to analyse these inks and see when/if a document was tampered with.
The VSC includes a unique microspectrometer. Adding further functionality to VSC workstations, this compact fibre-coupled spectrometer, with a 3x zoom microscope, captures real-time absorption, reflectance, fluorescence and transmitted spectra to be displayed on-screen in a simple graphical format. An ideal technique for the discrimination of visually similar inks, including ballpoint and liquid ink pens, micro spectrometry has also been demonstrated to be effective in the study of the sequence of intersecting lines.
Card Grading
in recent years, online trading, valuation and authentication of collectable trading cards has been transformed from a niche pastime into a multi-million dollar industry. As the market for trading cards continues to grow, collectors are increasingly turning to third-party grading companies to verify the authenticity and condition of their cards.
As Collectible Card Game (CCG) and Trading Card Game (TCG) items have increased in value, so too requires these items to be accurately verified, authenticated and graded (for quality). In addition to rarity, factors including authenticity, quality, and condition can significantly affect a card’s valuation. Due to this, card grading companies are increasingly turning to forster+freeman VSC technology as they seek to identify a forensic-level solution to card grading.
Card grading companies use VSC forensic technology to authenticate and grade high-value trading cards, employing various techniques to analyse the cards’ physical properties and characteristics.
Surface analysis under high magnification:
Using a VSC card graders are able to examine the surface of a card for evidence of alterations, alterations or irregularities. For example, they may look for signs of erasing, re-inking, or other modifications indicating forgery or tampering.
Multi-spectral UV-Vis-IR examination:
Full spectral imaging can reveal details on a card that may not be visible under normal lighting conditions. Card grading companies use UV light to detect hidden elements, such as watermarks or fibres, that can help confirm the card’s authenticity.
Spectrometry and Ink Analysis:
Using a high-level VSC8000/HS system, card grading companies can analyse the ink used on a card to estimate its age and determine its authenticity. Using micro-spectrometry, it is possible to analyse the chemical composition of the ink and compare it to known samples
Digital Imaging:
Card grading companies may use digital imaging techniques to capture high-resolution images of the card’s surface and features. These images can be used to compare the card to known authentic examples and identify any differences or irregularities. These images are often supplied to the card’s owner as part of the grading service.
Immigration and border security
One of the use cases for the VSC that is exponentially growing in popularity is the use of immigration and border security. Passports have become a highly valuable commodity, serving as vital travel documents that allow individuals to cross international borders. To protect these documents, governments commission more advanced security features designed to prevent counterfeiting and forgery. The technology in these passports is so advanced that it caused a shift in VSC technology.
VSCs combine multispectral illumination and unrivalled image quality for the optical examination of travel documents. Document examiners can quickly and efficiently perform a surface-level multispectral examination of the document as a first line of defence.
Furthermore, VSCs can now examine the strongest defence line embedded in travel documents, such as ePassports. The VSC can take the data embedded in the chip of the ePassport, decode it and display it to the examiner. The VSC includes Assure ID; this powerful software tool allows the examiner to extract the biometric data on the chip to perform 50+ forensic documents-specific tests, each with a pass/fail authentication.
Another way in which the VSC900 can detect cases of identity fraud is through Facial Identification.
Using an external camera, the VSC900 can perform facial recognition examinations, comparing a live image against a printed photograph and an embedded eChip image.
Unlike human examiners, the VSC900/Gemalto system can achieve a high level of accuracy while also minimizing the risk of false positives or false negatives with a false acceptance rate (FAR) of less than 1 in 10,000
Conclusion
The journey of foster+freeman’s VSC (Video Spectral Comparator) from its inception in 1978 to its current status as the premier range of QDE (Questioned Document Examination) workstations is a testament to innovation, adaptability and the pursuit of excellence in forensic technology. What started as a response to the need for a non-chemical, non-destructive method of identifying fingerprints on fabric evolved into a global success story with the ESDA and, eventually, the groundbreaking VSC.
Over the years, the VSC has undergone significant advancements, transforming from its early models with limited spectral range to today’s state-of-the-art workstations equipped with high-resolution cameras, sophisticated imaging capabilities, and cutting-edge software packages like the VSC SUITE. Its ability to utilize multi-spectral illumination, including UV and infrared light, allows examiners to delve into non-visible areas of the light spectrum, enabling the detection of hidden details crucial in questioned document examination.
The applications of the VSC have expanded far beyond its initial forensic focus. The VSC has become an indispensable tool in various fields, showcasing its versatility and adaptability to meet the evolving demands of modern technology. From forensic examination of documents, where it can differentiate between original and copied signatures, to its pivotal role in immigration and border security, the VSC plays a vital role in ensuring document authenticity and preventing fraud.
The intersection of technology and art conservation is another remarkable chapter in the VSC’s story. Its contribution to digitizing historical artefacts, such as the Beowulf manuscript, demonstrates the impact of this technology in revealing hidden details and preserving cultural heritage.
As we look back at the 40-year journey of the VSC, we recognize not only its technological evolution but also its significant contributions to diverse fields. From crime investigation to art restoration, the VSC stands as a symbol of precision, reliability, and innovation in the world of forensic technology. foster+freeman’s commitment to pushing the boundaries of what is possible has truly made the VSC the premier choice for professionals worldwide seeking the highest standards in questioned document examination.
Learn More
VSC® 900
The complete solution for hybrid document interrogations
Introducing a new VSC workstation for the hybrid physical and digital inspection of travel and identity documents, designed to meet the complex demands of immigration/border security applications.
The first in a new generation of hybrid VSC document examination systems, the VSC 900 provides examiners with a comprehensive suite of traditional and advanced tools for the interrogation and verification of passports, ID cards, visas, residence permits, and other questioned documents.
VSC® 8000/HS
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