Free webp to jpg
Image MIME Reference
Epson-ERF

Epson Raw Format

image/x-epson-erf
VS

Flexible Image Transport System

image/fits
FITS

A complete technical comparison of Epson Raw Format and Flexible Image Transport System — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.

Equal browser support

Feature Support

Feature Epson-ERF FITS
Transparency (Alpha) ✕ No ✕ No
Animation Support ✕ No ✕ No
Progressive Loading ✕ No ✕ No
HDR Support Yes Yes
EXIF Metadata Yes ✕ No
ICC Color Profile ✕ No ✕ No
Epson Raw Format
image/x-epson-erf
Extension
.erf
Container TIFF/EP
Compression Uncompressed / Lossless JPEG (ITU-T81)
Algorithm
NoneLossless JPEG
Color Depth 12-bit (Per Channel)
Developed by Seiko Epson Corporation
Released 2004
Magic Bytes
49 49 2A 00 or 4D 4D 00 2A
Full Epson-ERF reference →
Flexible Image Transport System
image/fits
Extension
.fits.fit.fts
Container FITS
Compression Uncompressed / Tile Compressed (Rice, GZIP)
Algorithm
UncompressedRiceGZIPHcompress
Color Depth 8-bit, 16-bit, 32-bit, 64-bit (Float/Double)
Developed by IAU FITS Working Group / NASA
Released 1981
Magic Bytes
53 49 4D 50 4C 45 20 20 3D 20
Full FITS reference →

Browser Support Comparison

Browser Epson-ERF FITS
Chrome Chrome
Firefox Firefox
Safari Safari
Edge Edge
IE IE (Legacy)
Epson-ERF

Epson-ERF Strengths

  • Preserves original raw sensor data, allowing extreme recovery of highlights and shadows compared to in-camera JPEGs
  • Utilizes the standard TIFF container structure, making it relatively easy for open-source software (like dcraw and LibRaw) to parse and decode
Limitations
  • Completely obsolete proprietary format tied to a defunct line of digital cameras
  • Requires parsing EXIF metadata to differentiate it from standard TIFF files programmatically
  • Cannot be natively viewed in web browsers or standard operating system image viewers without specialized codecs
FITS

FITS Strengths

  • The undisputed global standard for archiving and sharing astronomical data
  • Self-documenting: Headers are written in plain ASCII, ensuring data is readable decades later regardless of software
  • Supports incredibly high dynamic range, N-dimensional arrays, and complex binary tables
Limitations
  • No support in standard consumer software or web browsers
  • Uncompressed raw FITS files from modern telescopes can be excessively large
  • Does not use standard metadata models like EXIF or XMP, requiring specialized parsers

When to choose which format

Epson-ERF
Use Epson-ERF when…
  • Vintage Digital Photography (Epson R-D1)
  • Non-destructive Image Post-Processing
  • Raw Imaging Archival
FITS
Use FITS when…
  • Astronomy & Astrophysics
  • Space Telescope Data (Hubble, JWST)
  • Scientific Data Archiving
  • Spectroscopy
Share this comparison