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Photographic plate

Target medium in photography

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionApr 24, 2026
Entity authoritySource title only
Source-derived summary

Photographic plates preceded film as the primary medium for capturing images in photography. These plates, made of metal or glass and coated with a light-sensitive emulsion, were integral to early photographic processes such as heliography, daguerreotypes, and photogravure. Glass plates, thinner than standard window glass, became widely used in the late 19th century for their clarity and reliability. Although largely replaced by film during the 20th century, plates continued to be used for specialised scientific and medical purposes until the late 20th century.

Editorial summary

The public source identifies “Photographic plate” as target medium in photography. This brief keeps that definition visible, then builds a research path around Photographic, plate and Target.

Editorial reviewA concise reference frame for defining the subject, testing terminology and identifying the institution closest to the evidence. The current 83-word lead offers orientation but no explicit four-digit date, so chronology should not be assumed. The selected authority fields contribute no independent date. Its value is orientation rather than verdict, with Photographic, plate and Target providing the first useful test.
Editorial analysis

Why this record matters

A short description can identify a subject without explaining its stakes. For “Photographic plate”, the useful work is to connect “target medium in photography” to the records capable of establishing context and consequence.

Evidence profile

The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Apr 24, 2026.

Critical limits

Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

How to read it

Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.

Best used for
  • Subject orientation
  • Search vocabulary
  • Locating named sources
Verify next

The closest primary source, responsible institution and strongest cited specialist reference.

Three-step research path

  1. Establish the record: confirm the title “Photographic plate”, its source revision and the description used here.
  2. Expand the search: follow Photographic plate primary sources, Photographic plate archive and Photographic research across catalogues and specialist indexes.
  3. Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.

Questions for further research

  1. Which source most directly establishes the central claim about “Photographic plate”?
  2. Which institution is responsible for the underlying evidence?
  3. What terminology or title could unlock a more precise catalogue search?
Subject index

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Source & attribution

This entry incorporates text from “Photographic plate” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.