1:1 Macro Photography
Definition
Photography at a reproduction ratio of 1:1 (image sensor size equals subject size); the mandatory standard for all latent fingerprint photography before lifting or submitted as comparison evidence, achieved with a macro lens at its minimum focus distance.
- Reproduction ratio
- 1:1, sensor image size equals subject size
- Mandatory for
- Latent fingerprint photography before lifting
- Method
- Macro lens at minimum focus distance
- Purpose
- Produces comparison-quality evidence images
Common questions
Why must the photograph be taken before the print is lifted?+
Lifting can distort, smear or partially destroy ridge detail during transfer, so the 1:1 photograph is taken first to preserve an undistorted, measurable record of the print exactly as it appeared on the original surface.
What goes wrong if a latent print is photographed at a ratio other than 1:1?+
Ridge spacing and print size can no longer be measured accurately against a known print, which undermines a size-based comparison and can be challenged as unreliable in court.
Related terms
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- Barrier Filter
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- Basic Yellow 40 (BY40)
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- Cyanoacrylate (CA) Fuming
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- Ethyl Cyanoacrylate (ECA)
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- Lumicyano
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- Rhodamine 6G
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