Image MIME Reference
FastBid
FastBid Sheet
image/vnd.fastbidsheet
VS
Pentax Electronic File
image/x-pentax-pef
Pentax-PEF
A complete technical comparison of FastBid Sheet and Pentax Electronic File — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | FastBid | Pentax-PEF |
|---|---|---|
| Transparency (Alpha) | ✕ No | ✕ No |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | ✕ No | Yes |
| EXIF Metadata | ✕ No | Yes |
| ICC Color Profile | ✕ No | Yes |
FastBid Sheet
image/vnd.fastbidsheet
Extension
.fbs
Container
Proprietary FastBid Container
Compression
Proprietary
Algorithm
Unknown
Color Depth
Unknown
Developed by
FastBid, Inc. (Scott Becker)
Released
Late 1990s
Magic Bytes
Unknown (Proprietary)
Pentax Electronic File
image/x-pentax-pef
Extension
.pef
Container
TIFF-based (Proprietary)
Compression
Uncompressed / Proprietary Lossless
Algorithm
NonePentax Proprietary Lossless
Color Depth
12-bit (Per Channel), 14-bit (Per Channel)
Developed by
Pentax (now Ricoh Imaging Company, Ltd.)
Released
2003
Magic Bytes
49 49 2A 00 (Little-endian) or 4D 4D 00 2A (Big-endian)
Browser Support Comparison
| Browser | FastBid | Pentax-PEF |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
FastBid
FastBid Strengths
- Historically allowed the FastBid application to securely associate and load proprietary construction plans within its ecosystem
Limitations
- Completely obsolete and unsupported in modern software environments
- The official IANA registration of the .fbs extension causes widespread false positives, breaking modern parsers, text editors, and AI SDKs attempting to read FlatBuffers schemas
Pentax-PEF
Pentax-PEF Strengths
- Retains absolute maximum sensor data, enabling massive shadow recovery and highlight protection compared to compressed in-camera JPEGs
- White balance and sharpening are saved as metadata instructions rather than 'baked in', meaning they can be perfectly adjusted in post-production
- Utilizes the standard TIFF container structure, making it relatively straightforward for open-source software like LibRaw to parse
Limitations
- Proprietary format requires continuous updates to third-party processing software whenever Pentax releases a new camera model (unlike the open DNG format)
- Produces very large file sizes compared to standard web formats
- Cannot be directly embedded into web pages or used in standard HTML/CSS contexts
When to choose which format
FastBid
Use FastBid when…
- Legacy Construction Blueprints
- FastBid Estimating Software
- Causing .fbs MIME Type Conflicts (FlatBuffers)
Pentax-PEF
Use Pentax-PEF when…
- Professional Digital Photography
- Non-destructive Image Post-Processing
- Pentax Camera Archival