Infrared & Longwave Reflected UV Imaging of ‘superglue ... · and Infrared imaging over...

DCS5 APPLICATIONSInfrared & Longwave Reflected UV Imagingof ‘superglue’ fumed evidence

Application NoteISSUE 1

May 2017

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foster+freeman

DCS5: IR & Longwave R-UV Imaging of superglue fumed evidenceISSUE 1

May 2017

Equipped with a custom modified camera and UV-Vis-IR sensitive lens, theDCS 5 fingerprint imaging workstation enables examiners to search for evidence beyond the limits of human vision, detecting and visualising latent fingerprints within the UV and IR wavebands.

In fingerprint laboratories worldwide, it is common practice for non-porousitems of evidence to be fumed with cyanoacrylate (superglue), to developfingerprint ridge detail, before being treated with a chemical dye/stain, tocreate contrast between the fingerprint and background surface.

The fume/stain technique is widely used and largely successful, enabling examiners to reveal fingermarks on a wide variety of evidence types. However, the process of fuming and then staining evidence is time-consumingand costly, requires the use of potentially harmful chemicals, and is not suitable for use with all substrates.

In this study, it is demonstrated that by examining cyanoacrylate fumeditems of non-porous evidence with Reflected Infrared and Longwave Reflected UV, the vast majority of fingerprints may be revealed without theneed for a subsequent dye/stain treatment.

Examinations, under Reflected Infrared and Longwave Ultraviolet, are quickand easy to perform with results being displayed on screen in real-time. Theresulting fingerprints demonstrate a good quality of ridge detail while thevery nature of Reflected UV/IR imaging greatly suppresses background information to produce excellent contrast.

A P P L I C AT I O N I M A G E S

Longwave Reflected-UV 1Curved glassPrinted packagingPlastic carrier bagPharmaceutical packagingDrinks canHair product containerMobile telephone

Reflected-IR 2Background suppression Drinks canPharmaceutical packagingPrinted boxGlossy printed labelGreetings cardPlastic bottle/printed labelFruit juice cartons

Dual-Wavelength Examination 3Currency

A turnkey system operated via a Windows PC, theDCS 5 Core Imaging System includes all components required to image and enhance fingerprints in the visible spectrum.

System EssentialsPro-grade copy standDesktop PC & 32” 4K monitorPhotographic Accessories

ImagingNikon D5 DSLR camera Infrared Imaging Filters

IlluminationFLS Bandpass Filtered Light SourceHalogen Light SourceFibre Optic Light Guides

UV Light SourcePowerful directional 365nm UV light source.

60mm UV Transmitting Lens This quartz/fluorite lens, is essential for Reflected UV Imaging but also provides excellent results in the Vis and IR.

UV Imaging Filter Set330-385nm bandpass filter

In order to accommodate the differing requirements of fingerprint laboratories worldwide, DCS 5 is a modular system that can be expanded through the addition of application specific modules.

In order to perform the applications in this study, the DCS 5 Core imaging system must be equipped with the additional Reflected UVImaging module. For superior results when imaging Reflected-IR, it is recommended that the additional Infrared Imaging modulealso be selected.

DCS 5 Required Hardware

foster+freeman

DCS 5 Core Reflected UV Imaging+

Additional camera lens, light source and filters essential for R-UV imaging.

Crime-lite 8x4MK4 IR Light SourcePhotographic ring light for infrared imaging - Blue, Red and N-IR wavelengths

IR Imaging AccessoriesIncludes slot-in viewing filters and sample pots of fpNatural IR fluorescentpowders

Infrared Imaging+

Additional light source and filters for Fluorescence & Reflected-IR imaging.


May 2017foster+freeman

Fingerprints on Curved Glass

A notoriously difficult surface on which to photograph fingerprints, examiners wishing to obtain prints from curvedglass surfaces will in most cases resort to using dusting powders and fingerprint lifting tape. While this technique iswidespread it does risk permanent damage to the print.

Reflected-UV imaging eliminates the problem of glare andthe reflection of visible light from the bottles surface leavinga clearly visible, high contrast fingerprint.

Illumination Halogen VisibleLens 60mm UV/IRFilter Vis Pass

DCS EnhancedIllumination Crime-lite 82S UVLens 60mm UV/IRFilter UV Pass

Longwave Reflected-UVUV radiation (wavelengths of light shorter than 400nm) is invisible to the naked eye. However, by equipping the DCS-5 camera with the60mm UV Transmitting Quartz Lens and 330-385nm bandpass filter, it is possible to record the UV radiation that is reflected back fromthe subject to reveal impressive results from previously difficult subjects.

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Illumination: Crime-lite 82S UV (365nm)Light Filtration: 330-385nm Bandpass filter (blocks all visible light)Image Capture: 60mm UV Transmitting Quartz Lens

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Illumination Crime-lite 82S UVLens 60mm UV/IRFilter UV Pass

Longwave Reflected UV examination of two colourful crisp packets, fumed with cyanoacrylate. No additional enhancements applied.

Crisp Packet - Printed Packaging

Crisp Packet - Printed Packaging

DCS Enhanced





Longwave Reflected UV examination of printed plastic carrier bag, fumed with cyanoacrylate. No additional enhancements applied.

Plastic Carrier Bag

DCS Enhanced





Longwave Reflected UV examination of miscellaneous items, fumed with cyanoacrylate. No additional enhancements applied.

Pharmaceutical Packaging

Drinks Can

Hair Product Container

Mobile Phone

DCS Enhanced



Reflected-IRWhile infrared radiation (wavelengths of light longer than 700nm) is invisible to the naked eye, it may be detected by most digital SLRcameras. However, as infrared wavelengths are not required for conventional (visual) photography, camera manufacturers install IRblocking filters to eradicate wavelengths of light above 700-800nm.

The camera supplied with DCS 5 systems has been custom-modified by foster+freeman to enable full-spectrum photography, making itpossible to capture images of IR light being absorbed or reflected by different surfaces.

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Illumination: Crime-lite 8x4MK4 Light Filtration: 850nm Sharp-cut filter (blocks all visible light)Image Capture: 105mm Vis-IR Macro Lens

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Background SuppressionPerhaps the greatest advantage of Longwave Reflected UVand Infrared imaging over ‘traditional’ visible imaging techniques is the natural suppression of troublesome backgrounds.

In this example a fingerprint, fumed with cyanoacrylate, hasbeen developed on a multi-coloured drinks can. Despite thelack of visible contrast (white ridge detail on a white area ofthe can) it has been possible, using reflected-IR imaging, tosuppress the background to a point that visible contrast canbe discerned.

Once subjected to DCS digital enhancement, a fingerprint ofidentifiable quality has been revealed.


DCS EnhancedIllumination Crime-lite 8x4MK4 IRLens 60mm UV/IRFilter IR Pass




Illumination Crime-lite 8x4MK4 IRLens 60mm UV/IRFilter IR Pass

Reflected IR examination of miscellaneous items, fumed with cyanoacrylate. No additional enhancements applied.

Drinks Can

Printed Box

Pharmaceutical Packaging

Glossy Printed Label

DCS Enhanced





Reflected IR examination of miscellaneous items, fumed with cyanoacrylate. No additional enhancements applied.

Plastic Bottle / Label

Greetings Card

Orange Juice Carton

Apple Juice Carton

DCS Enhanced


May 2017foster + freeman

foster + freeman

www.fosterfreeman.com

USA Sales Office46030 Manekin Plaza | Suite 170 | Sterling | VA 20166 | USA

Tel: 888 445 5048 | [email protected]

Head Office, UK Sales OfficeVale Park | Evesham | WR11 1TD | United Kingdom

Tel: +44 (0)1386 768 050 | [email protected]

Benefits of dual wavelength examinationIn order to obtain the best quality of results and to reveal as many fingermarks as is possible, reflected-IR and longwave reflected-UVimaging are techniques best used in tandem.

In the example below, a polymer banknote has been fumed with cyanoacrylate before being examined under both reflected-UV (top right image) and longwave reflected-infrared (bottom right image).

In each of the two images a number of fingerprints are clearly visible. However, on closer inspection it can be seen that the two imaging techniques have had varying degrees of success in terms of sufficiently suppressing the background to create contrast.

Only by examining the note under reflected-IR and longwave reflected-UV are we able to retrieve the maximum quality and quantityof fingerprint data.





Recognised for innovation in the field of latent fingerprints, our product range includes advanced systems for the development of fingerprints using traditional time honoured methods alongside new and novel techniques developed exclusively by foster+freeman.

Recent peer-reviewed papers include:Seeing into the infrared: A novel IR fluorescent fingerprint powder (2015)•

NIR-NIR fluorescence: A new genre of fingermark visualisation techniques (2016)•

Sunlight-activated near-infrared phosphorescence as a viable means of latent fingermark visualisation (2017)•

Fingermark visualisation on uncirculated £5 (Bank of England) polymer notes (2017)•

The use of infrared fluorescent reagents for the enhancement of latent fingerprints from notoriously troublesome backgrounds (2017)•

Infrared & Longwave Reflected UV Imaging of ‘superglue ... · and Infrared imaging over...

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