Skip to main content
Heritage Science

Table 1 Summary of methods and technologies used for this study with expected outcomes

From: Application of multi-modal 2D and 3D imaging and analytical techniques to document and examine coins on the example of two Roman silver denarii

Method

Sensor/analytical tools used

Expected data outcome

Conclusions

Photography

DSLR (Nikon D200)

Digital images = pixel-data

Appearance of the coin, text and image, corrosion, etc.

Focus-stacking

DSLR Canon EOS 600D + Cognisys Stackshot

Digital microscopy Hirox KH-7700

Digital images = pixel-data, 3D surface geometry

Surface image in high-resolution and high depth of field, imagery with high photographic detail

Digital microscopy

Digital microscopy Hirox KH-7700

Same as above

Same as above

Dome-photography/PTM/RTI

DSLR camera in nadir position + lights (flash or LED lights) in a half-dome, four arrangements used in this research

Raw digital image data and colour calibrated images according to camera/lens/resolution

Surface visualisation with interactive lighting of near-flat objects, no 3D information

Photometric stereo

Same as above, (machine vision) camera and robotic light with rotation table in dark space

Same as above + coloured surface geometry

3D surface geometry for near-flat objects (in colour) at high detail

Photogrammetry and SfM

DSLR + lights

Raw digital image data, colour calibrated images, 3D surface point cloud, 3D surface model

Surface geometry in 3D and surface colour

3D scanning

3D laser scanner (IDENTIK 300L Arius Technology Scanner, Micro-Epsilon, NextEngine), 3D structured light scanner (MechScan 3D Macro, SmartSCAN HE with 8MP stereo cameras) (complemented by analytical balance)

Same as above; volume [cm3], plus in combination with the analytical balance weight: density [g/cm3]

Surface geometry in 3D and surface colour; determination of volume, material composition estimation due to known material densities

microCT

Microtomograph Nanotom 180 (GE Phoenix), measurement conditions

X-ray images

Internal structure, rendered 3D model, film of slices (link to Additional files 1, 2, 3, 4)

SEM/EDX

SEM (JEOL JSM 7600F) coupled with EDX

Elemental spectra with characteristic peaks, tables of elemental % per sampling area, 3D Image of the surface, elemental analysis to 15 μm surface depth

Elemental analysis of coins, elemental matrix maps of surface, surface image with 3D visualisation

XRF

ARTAX 200, ARTAX 800, S1 Titan handheld XRF spectrometer (Bruker)

Elemental spectra with elemental analysis to 150 μm surface depth

Surface chemistry of the coin, multi-elemental analysis

Gas pycnometry

Pycnometer Micrometrics AccuPyc II 1340 (complemented by analytical balance)

Volume [cm3], plus in combination with the analytical balance weight: density [g/cm3]

Determination of volume, material composition estimation due to known material densities

Analytical balance

Kern, Sartorius B120S

Weight [g]

Same as above

Back to article page