ESDA Lift
Definition
The permanent transparent Mylar sheet carrying the toner-developed image of the indented writing, produced by ESDA processing; suitable for court exhibition and long-term case-file storage.
- Material
- Transparent Mylar sheet
- Produced by
- ESDA toner development
- Purpose
- Court exhibit, case-file archival record
Common questions
Why is the ESDA lift itself, rather than a photograph of it, typically retained as the exhibit?+
The lift is the primary physical record of the toner-developed image and can be re-examined or re-photographed under different lighting later, whereas a photograph is a fixed secondary representation that cannot be re-analysed the same way.
Can more than one ESDA lift be produced from the same indented page?+
More than one lift can sometimes be pulled from the same indented sheet, but image quality drops with each additional pass as the charge pattern is used up, so examiners usually take the clearest lift from an early pass rather than relying on a later one.
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- Corona Wire
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- ESDA (Electrostatic Detection Apparatus)
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