Retrieving Tarnished Daguerreotype Content Using X-ray Fluorescence Imaging—Recent Observations on the Effect of Chemical and Electrochemical Cleaning Methods

Stark, Alison; Filice, Fraser; Noël, James J. (ORCID:0000000334674778); Martin, Ronald R.; Sham, Tsun-Kong (ORCID:0000000319286697); Finfrock, Yanhui Zou; Heald, Steve M.

doi:10.3390/heritage4030089

DOE OSTI · 1812107

Retrieving Tarnished Daguerreotype Content Using X-ray Fluorescence Imaging—Recent Observations on the Effect of Chemical and Electrochemical Cleaning Methods

Stark, Alison·Filice, Fraser·Noël, James J. (ORCID:0000000334674778)·Martin, Ronald R.·Sham, Tsun-Kong (ORCID:0000000319286697)·Finfrock, Yanhui Zou·Heald, Steve M.

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Abstract

We report a study on the effect of chemical and electrochemical cleaning of tarnished daguerreotypes observed using X-ray fluorescence (XRF) microscopy with a micro-focussed X-ray beam from a synchrotron source. It has been found that, while both techniques result in some success depending on the condition of the plate and the experimental parameters (chemical concentration, voltage, current, etc.) the effect varies, and cleaning is often incomplete. The XRF images using Hg Lα,β at an excitation energy just above the L3 edge threshold produce fine images, regardless of the treatment. This finding confirms previous observations that if the bulk of the image particles remains intact, the surface tarnish has little effect on the quality of the original daguerreotype image retrievable from XRF.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY X-ray fluorescence imaging chemical cleaning daguerreotype electrocleaning synchrotron tarnish

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Stark, Alison, Filice, Fraser, Noël, James J. (ORCID:0000000334674778), Martin, Ronald R., Sham, Tsun-Kong (ORCID:0000000319286697), Finfrock, Yanhui Zou, Heald, Steve M.. 2021-08-05. Retrieving Tarnished Daguerreotype Content Using X-ray Fluorescence Imaging—Recent Observations on the Effect of Chemical and Electrochemical Cleaning Methods. https://doi.org/10.3390/heritage4030089

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