Use the complete card identity—family, product line, capacity and part number—to find its specifications. “Extreme” is a product-line name; the useful answer for a shoot comes from matching a particular card to a camera, recording mode, reader and working environment.
Build a card identity record
- Photograph both sides and transcribe the full part number, capacity, card-family logo and speed markings. Include “PRO” when it appears in the name.
- Match those details to a manufacturer document. Keep its date and footnotes with your record; a similarly named card from another generation may have different specifications.
- Check the camera’s manual and supported-card list for the exact recording mode and firmware. Then identify the reader used for offload.
- Resolve ambiguous or unreadable markings before buying a replacement or assigning demanding work. Use the card-family identification guide when the physical format is unclear.
Read a dated specification in context
SanDisk’s June 2016 Extreme CompactFlash datasheet (PDF) provides a useful capacity-specific example. The following figures belong to that documented CF family; match an actual card before using them.
On a narrow screen, swipe the table or focus it and use the arrow keys.
| Capacity in that datasheet | Maximum read claim | Maximum write claim |
|---|---|---|
| 16 GB | Up to 120 MB/s | Up to 60 MB/s |
| 32, 64 or 128 GB | Up to 120 MB/s | Up to 85 MB/s |
The same sheet specifies VPG-20 for a 20 MB/s minimum sustained video-write rate, subject to compatible use. Its upper read/write figures come from internal testing, with host-dependent results. The manufacturer’s product page also identifies individual part numbers; retain that identity alongside the numbers you record.
For camera recording, use the camera’s required writing performance and approved media. For copying to a computer, evaluate card reading, reader, connection and destination together. A fast offload result cannot establish how a camera behaves during a long recording.
Turn an outdoor claim into a defined requirement
The 2016 datasheet reports temperature testing from −25°C to 85°C. The product page lists an operating range of −25°C to 85°C for its identified 32 GB model SDCFXSB-032G-G46. Apply the claim to the documented model and conditions. Check the camera, battery and reader specifications separately.
- Operating or storage: establish whether the equipment is powered, recording or being transported, and find the corresponding limit.
- Exposure: record the expected temperature and any water, dust, impact or condensation concerns. Find explicit conditions and exclusions for each relevant component.
- Evidence: distinguish a manufacturer specification, a defined test and one photographer’s successful trip. A field account needs a named product, conditions and outcome to support a narrow conclusion.
- Unknowns: ask the manufacturer about missing conditions. Keep an unanswered requirement unresolved rather than assigning a rating from a product name.
Accept the card for a specific workflow
After securing any needed existing files, prepare the card according to the camera manufacturer’s instructions. Use expendable recordings to exercise the intended mode and duration. Review them in the camera, offload them through the chosen reader and open the copies in the intended software. Record the setup and any errors.
A successful rehearsal supports that workflow under the observed conditions. Keep verified backups during the real job and investigate unexpected write errors or disconnects before further use. The CompactFlash purchase and acceptance record provides fields for the model, support evidence and test result.