Recovering Past Reflections: X-ray Fluorescence Imaging of Electrocleaned 19th Century Daguerreotypes
Bibliographic record
Abstract
The first commercially viable photographic image, the daguerreotype, captured images for a span of approximately 20 years (1839–1860). DeDterioration now disfigures many of these valuable images. One proposed restoration method is an electrochemical process. However, its safety and effectiveness are still under debate within the conservation community as the effects of this treatment, and its physical and chemical impact on the daguerreotype image, have not yet been analyzed in depth. This study used synchrotron-based micro-X-ray fluorescence to map the elemental distribution pre- and post-electrocleaning on 19th century daguerreotypes using both soft and hard incident X-rays. X-ray absorption spectroscopy was used to probe local chemistry before and after cleaning. Two different electro-treatment methods were compared: the original method proposed by Barger and a second put forward by Wei. When used correctly, both processes significantly reduced the S and Cl surface contamination without dulling the surface. However, both electrochemical methods used in this study resulted in a loss of Hg and Au from the surface. In all cases, the Hg distribution tracks with image particle density allowing the retrieval of full portraits from entirely corroded daguerreotypes, suggesting that Hg concentration may be a useful proxy for the original image.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.007 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".