A documentation photograph is only as useful as the information that comes with it. Who took it, when, with what equipment, at what magnification, under which light, and how it was processed: without this, images cannot be checked, compared or trusted. This final lesson of the course explains what technical information to record, how to store it in metadata and logs, how to report processing honestly, and why some fields require a strict chain of custody for images.
What is technical metadata?
Technical metadata is the information describing how an image was created and processed. Some is recorded automatically by the camera as EXIF data; the rest must be added by the photographer. Metadata types (EXIF, IPTC and XMP) were introduced in folders, naming systems and metadata. In documentation work, this information is part of the record, not an optional extra.
What to record
| Category | Examples | Recorded automatically? |
|---|---|---|
| Identification | Image ID, subject or specimen number, project, location | No |
| Date, time and photographer | Capture date and time, name | Date and time yes (if camera clock is correct); name via template |
| Camera and lens | Model, serial number, focal length | Mostly yes |
| Exposure | Aperture, shutter speed, ISO | Yes |
| Magnification and scale | Magnification, scale used, calibration | No |
| Lighting | Type, positions, polarization, color target used | No |
| Stacking or combining | Number of frames, step size, software | No |
| Processing | Software and version, adjustments applied | Partly, in sidecar files |
Tip:Check the camera clock before each session. Wrong dates and times are one of the most common errors in documentation records.
Storing the information
- Embedded metadata: use templates to add identification, creator and project fields to every file.
- Sidecar files: editing software stores processing steps beside RAW files; keep them together, as in folders, naming systems and metadata.
- Session logs: a simple spreadsheet or form recording setup details for each session.
- Setup photographs: images of the camera, lighting and subject arrangement, as in reproducible photographic conditions.
- Consistent file naming: IDs that link images to logs and specimens.
Reporting processing honestly
When images are published or used as evidence, describe how they were processed:
- State which adjustments were applied and that they were applied to the whole image, following the integrity rules in scientific and technical documentation.
- Report combining methods, such as focus stacking from focus stacking or exposure blending.
- Name software and versions when relevant.
- Keep original files available on request.
Chain of custody
In forensic, legal and some regulatory work, images may be used as evidence. Chain of custody means documenting who handled the images and files, when and how, from capture to presentation, so their integrity can be demonstrated. Practices include:
- Preserving untouched original files in secure storage.
- Recording every transfer, copy and access.
- Using checksums to show files have not changed, as in archiving and long-term preservation.
- Working only on copies and documenting all processing.
Warning:Requirements vary by country, institution and case. Always follow the specific procedures of the organisation you work for.
Data management and retention
Technical and scientific images often must be kept for years, with their records. Combine the backup and archiving practices from backup, redundancy and data protection and archiving and long-term preservation with your organisation's data management and confidentiality rules.
Common mistakes
- Relying only on automatic EXIF: magnification, lighting and scale are missing.
- Wrong camera clock: dates and times are unreliable.
- Undocumented processing: images cannot be verified.
- Overwriting originals: integrity cannot be shown.
How professionals record and report
Scientific, museum, clinical and forensic photographers use metadata templates, session logs, consistent IDs and secure storage. They report processing clearly and keep originals untouched. This discipline makes their images trustworthy for research, publication, conservation and court. You have now completed the course on macro, close-up, scientific and technical photography. Next, you will explore creative photography, starting with creative photography and intentional experimentation.
Practical examples
A museum documentation project
- Situation
- A museum needs 500 objects photographed so future researchers can rely on the images.
- What to do
- You use IDs matching the catalogue, a metadata template, a session log of setup and lighting, color targets and untouched originals with processed copies.
- Why it works
- Complete records make every image traceable and verifiable.
- Result
- A trustworthy image collection that can be used for decades.
Images for a research paper
- Situation
- A journal asks how your focus-stacked images were made.
- What to do
- You provide the number of frames, step size, software, whole-image adjustments and the original files.
- Why it works
- Clear reporting demonstrates integrity.
- Result
- The images are accepted without concerns.
Key points
- Technical metadata records how images were made and processed.
- Record identification, date and photographer, equipment, exposure, magnification, lighting, combining and processing.
- Store information in embedded metadata, sidecars, session logs, setup photos and consistent file names.
- Report processing honestly and keep originals available.
- Evidence work requires chain of custody with secure originals, records and checksums.
Frequently asked questions
What is technical metadata in photography?
Does the camera record everything I need?
What is chain of custody for photographs?
How should I report image processing?
Conclusion
Technical metadata and honest reporting make documentation photographs trustworthy. Record everything the camera does not, store it consistently, report processing clearly, protect originals and follow chain-of-custody procedures where required. You have now completed the macro, close-up, scientific and technical photography course.
Finished reading? Track your progress through Macro and technical.