Choose Your Fighter: Picking the Perfect Video Spectral Comparator

In questioned document examination, the video spectral comparator is a powerful all-in-one device that brings together an extensive arsenal of tools for document analysis, handwriting examination, and much more.

But not all video spectral comparators are built for the same challenges. From the device’s size and optical capabilities to its light sources, imaging modes, examination tools, and specialized features, every detail can determine how well it fits a particular workflow.

This guide is designed to help decision-makers in law enforcement, passport control, forensic laboratories, financial institutions, and other organizations navigate the features and capabilities of video spectral comparators across the Regula product line.

The current Regula lineup of video spectral comparators consists of four models:

• Dual-Video Spectral Comparator Regula 4308M

• Video Spectral Comparator Regula 4307

• Video Spectral Comparator Regula 4306M

• Video Spectral Comparator Regula 4305DMH

Of course, size is not the only difference. As the model numbers go up, so do their capabilities, including built-in tools such as a spectrometer or hyperspectral analysis module, an integrated PC, a wider range of light sources, higher camera resolution, and other features.

Let’s see in detail.

The Regula 4308M is the most advanced video spectral comparator in the entire Regula lineup, designed for laboratory environments. Its substantial size allows it to accommodate objects ranging from ID cards to oversized items such as antique hotel registry books, A3 archival documents, or paintings. Removable side panels make it easy to place objects inside, while the movable top camera enables precise focusing.

It is an indispensable tool for organizations requiring the utmost accuracy and reliability, including state-level forensic laboratories and police laboratories, passport control agencies, and national banks.

Apart from size, what makes the Regula 4308M great is the presence of two cameras (top and bottom), an impressive 320x magnification, and a movable object stage.

The capabilities of the optical system, with its 320x magnification, make it possible to detect the slightest changes in strokes or the structure of the paper. Once a suspicious area is found, the bottom camera allows the examiner to instantly switch to the reverse side to identify possible traces of chemicals that have penetrated the paper, added strokes, differences in stroke pressure, and other irregularities.

Such non-contact examination is particularly valuable for precise positioning of objects under extremely high magnification, as well as for examining old, damaged, fragile, or irregularly shaped objects.

Besides the above mentioned features, the Regula 4308M is equipped with unparalleled capabilities, including:

• 40+ types of light sources: 99% of these are LEDs, ensuring exceptional precision and durability.

• Dual filter turret system: greater control over the observation band, improved ink differentiation, and reduced glare. 

• Motorized oblique lights: providing a tailored approach to any object, taking into account its thickness and the depth of the examined strokes, which increases the efficiency of the results.

• Module for hyperspectral analysis: ink differentiation in documents and banknotes.

• Built-in spectrometer: for measuring color characteristics — absorption, reflection, and fluorescence — of inks.

• 3D visualization module: constructs a three-dimensional model of the document surface to distinguish the sequence of strokes in hand-written documents.

• Full-page blind embossing visualization: enhanced visibility of surface structures across the entire ID card or passport data page.

All these tools and modules are designed to accurately determine whether a document is genuine or forged, including alterations to the document’s original content (photo substitution, additions, erasures), distinguishing between different types of ink and paint, identifying the printer used to print the document by decoding the yellow dots pattern, and other types of examinations.

Let’s take as an example narrowband light sources. They are intended for examination of infrared luminescence and can help to reveal additions made in handwritten texts and alterations made by etching and erasure; and, of course, to examine infrared luminescence in travel documents and banknotes.

The Regula 4308M has 12 narrowband light sources of different wavelengths, starting from 395 nm and going up to 735 nm. They can be used separately, intensified, or blended with other narrowband light sources. The right-for-that-wavelength filters are chosen automatically, but they can be changed for the sake of experimentation.

Space can become a deciding factor when choosing a video spectral comparator. Limited room may make it impractical or even impossible to accommodate a large device like the Regula 4308M. In such cases, forensic experts may need something much more compact and affordable while retaining many of the capabilities and the overall feel of a flagship model.

That’s where the Regula 4306M comes in: a more compact video spectral comparator designed to bring flagship-level functionality to environments where space matters.

Think of the Regula 4306M as the younger brother of the Regula 4308M, so a direct comparison is the best way to understand what sets them apart.

As we can see, the Regula 4306M offers a strong set of capabilities, albeit with more modest specifications than the flagship model. However, some of these limitations can be compensated for. For example, while the device does not feature a built-in spectrometer, it can be easily paired with the portable Regula 5006M spectrometer. This addition enables full spectral analysis without compromising the device’s space-saving design.

The Regula 4306M features manually adjustable oblique light sources, but the illumination angle is still calculated automatically, allowing the examiner to include the exact angle value in examination reports.

Even thick documents can be examined with the Regula 4306M by removing the object stage to extend the available working area.

The Regula 4307 is the most customizable video spectral comparator, designed for professionals who have a precise understanding of the features and tools needed to meet their specific examination requirements.

It can feature a built-in PC, a spectrometer, a 3D visualization module, anti-Stokes light sources, a 14 MP camera, and other features and tools. This video spectral comparator strikes the perfect balance in size between the Regula 4308M and the Regula 4306M.

Thanks to this flexibility, the Regula 4307 can be tailored to both operational requirements and budget constraints. This makes it particularly suitable for regional laboratories looking to maximize their available resources.

Finishing the list is the most compact video spectral comparator, the Regula 4305DMH. One of its key advantages is its operational flexibility, offering both manual controls and software-based operation for access to its full range of examination features and tools. It can also be powered via a 12 V in-car socket, making it particularly suitable for mobile laboratories and on-the-go forensic examinations.

Despite its small size, the Regula 4305DMH packs an impressive array of 21 light sources. Its capabilities can be expanded even further with plug-in tools such as a thermostage, the Regula 4147 spectral luminescent magnifier for examining anti-Stokes pigments, or the Regula 4197 magneto-optical visualizer for examining magnetic inks.

This combination of compact size, flexible operation, and expandability makes the Regula 4305DMH particularly well suited to small laboratories, Schengen buses, and other mobile laboratory setups.

With four models offering different combinations of size, functionality, mobility, and customization, the choice ultimately comes down to your working environment and the tasks your laboratory performs. Start with a simple question: what do you need your video spectral comparator to do, and under what conditions will you use it?

• Choose the Regula 4308M if you need maximum capabilities. If you represent a central forensic laboratory handling a high volume and wide variety of examinations, the Regula 4308M is the most appropriate choice. It makes the most sense when functionality takes priority over footprint and budget.
• Choose the Regula 4306M if you want flagship capabilities in a smaller package. If you run a central or well-equipped forensic laboratory and cannot accommodate the Regula 4308M, or its level of functionality exceeds your budget, then it is a perfect case for choosing the Regula 4306M.
• Choose the Regula 4307 if you want a tailored device to your unique needs. Not every laboratory needs the maximum number of features. Sometimes the better approach is to pay for the exact combination of tools your workflow requires. If you already have clearly defined examination procedures and know which light sources, imaging tools, and additional modules your experts actually use, the Regula 4307 offers the greatest flexibility.
• Choose the Regula 4305DMH if mobility and simplicity matter most. If examinations need to be performed outside a conventional laboratory, or if you simply need a more compact and straightforward solution, consider the Regula 4305DMH.

If you’re still in doubt, identify your primary constraints. For example, if a built-in spectrometer then it narrows down the choice for a particular model. Besides, our team is more than pleased to provide competent advice and assistance in choosing the video spectral comparator that will meet your expectations.