VSC (Video Spectral Comparator)
Definition
A multispectral imaging instrument used in document examination; illuminates the document at multiple wavelengths (UV, visible, near-IR, IR) and captures fluorescence and reflectance images, allowing ink discrimination, overwriting detection, and obliterated-text recovery.
- Common models
- Foster and Freeman VSC8000 and VSC80i
- Wavelength range
- UV (254 nm) through visible to near-infrared (~1000 nm)
- Primary uses
- Ink discrimination, overwriting detection, obliterated text recovery, document forgery analysis
Common questions
What does VSC do that regular light can't?+
A VSC illuminates documents across a wide range of wavelengths from UV through infrared, revealing ink differences that look identical under normal white light. This lets examiners spot overwriting, detect ink discrimination, and recover obliterated text that's invisible to the naked eye.
Is the VSC destructive to documents?+
No. The VSC is a non-destructive imaging instrument, meaning you can examine documents without damaging them. It simply illuminates and photographs them at different wavelengths.
What wavelengths does the VSC use?+
The VSC illuminates documents across UV (starting at 254 nm), visible light, and near-infrared through about 1000 nm. This broad spectrum helps capture both fluorescence and reflectance images, giving multiple views of the same document.
Related terms
- ASTM E2285 / E2286
- The two ASTM International standards governing forensic ink examination: E2285 covers TLC-based ink alteration examination; E2286 covers HPLC-based ink comparison. Both are...
- Ballpoint Ink
- An oil-based, high-viscosity ink using a resin binder (alkyd or polyamide) in a high-boiling solvent (phenoxyethanol or benzyl alcohol), with triphenylmethane dyes...
- Check Washing
- A cheque alteration technique in which organic solvents dissolve the original ink entries while leaving the pre-printed bank security printing intact, allowing...
- CTS-2010 (Cheque Truncation System)
- RBI's standard for cheque security features in India, requiring watermark, void pantograph, UV-reactive printing, and MICR E-13B encoding; cheques not meeting CTS-2010...
- Digital Signature Certificate (DSC)
- A cryptographic certificate issued by a Controller of Certifying Authorities (CCA)-licensed CA in India (or equivalent trust-service provider under eIDAS in the...
- Embossed Seal Counter-Matrix
- The female die component of an embossing seal press, whose surface marks and imperfections transfer as positive elements in the paper impression...
- Error Level Analysis (ELA)
- A technique that re-compresses a JPEG at a controlled quality setting and maps the pixel-level difference between the re-compressed and original images....
- ESDA (Electrostatic Detection Apparatus)
- A non-destructive technique for detecting indented impressions on paper caused by writing pressure. A physical ink signature on paper produces detectable ESDA...
- HPLC-DAD
- High-performance liquid chromatography with diode-array detection. Separates ink dyes on a C18 column and records UV-visible spectra at each elution point, providing...
- Iron-Gall Ink
- A historical ink formulation of ferrous sulphate, tannic acid (from oak galls), and gum arabic. The ferrous-tannate complex oxidises to brown ferric-tannate...
- MICR E-13B
- The Magnetic Ink Character Recognition font standardised by the American Bankers Association and adopted by the RBI for CTS-2010; uses iron-oxide magnetic...
- Phenoxyethanol
- The primary high-boiling solvent in most modern ballpoint ink formulations. Its progressive evaporation from the dried ink film after writing is the...
Explained in these topics
- Cheques, Demand Drafts, Stamps and Seals: Forgery PatternsA multispectral imaging instrument used in document examination; illuminates the document at multiple wavelengths (UV, visible, near-IR, IR) and captures fluor...
- Ink Chemistry: TLC, HPLC, Raman and the Video Spectral Comparator WorkflowA non-destructive imaging instrument (Foster and Freeman VSC8000 / VSC80i) that illuminates documents at wavelengths from UV (254 nm) through visible to near-i...