What is ORF?

ORF (Olympus Raw Format) files contain unprocessed image data from Olympus and OM System Micro Four Thirds cameras. They preserve the original 12-bit sensor data without in-camera JPEG processing, enabling photographers to adjust white balance, exposure, and colors during post-processing without quality loss. ORF files include embedded JPEG previews and comprehensive EXIF metadata including Art Filters and camera settings.

ORF is used by professional photographers shooting Olympus OM-D and PEN series cameras (E-M1, E-M5, E-P7, etc.) for travel photography, street photography, wildlife, and video stills. The Micro Four Thirds sensor produces smaller ORF files (typically 15-25 MB) compared to full-frame RAW formats while maintaining excellent image quality. Popular with photographers who value compact camera systems.

Did you know? ORF files capture Olympus's in-body image stabilization data for analysis!

History

Olympus developed ORF format for their digital cameras, later continuing the format under the OM System brand after restructuring.

Key Milestones

  • 2003: ORF format introduced
  • 2009: Micro Four Thirds adoption
  • 2012: OM-D series launches
  • 2016: Improved compression
  • 2021: OM System brand transition
  • Present: Standard for OM System cameras

Key Features

Core Capabilities

  • 12-Bit Color: 4,096 levels per channel
  • Art Filters: Embedded filter data
  • IBIS Data: Stabilization information
  • EXIF Rich: Comprehensive metadata
  • Compact Size: Smaller than full-frame RAW
  • JPEG Preview: Quick viewing

Common Use Cases

Travel

Lightweight system photography

Street

Discreet urban photography

Wildlife

Nature and bird photography

Post-Production

Flexible editing workflow

Advantages

  • Excellent image quality
  • Smaller file sizes than full-frame
  • Full editing flexibility
  • 12-bit color depth
  • Fast camera write speeds
  • Art Filter data preserved
  • Wide software support

Disadvantages

  • Smaller sensor than full-frame
  • Requires RAW processing
  • Proprietary Olympus format
  • Not as widely used as Canon/Nikon
  • 12-bit vs 14-bit (other brands)
  • Needs specialized software

Technical Information

Format Specifications

Specification Details
File Extension .orf
MIME Type image/x-olympus-orf
Color Depth 12-bit (4,096 levels per channel)
Sensor Micro Four Thirds
Compression Lossless compressed
Typical Size 15-25 MB

Common Tools

  • Adobe: Lightroom, Photoshop Camera Raw
  • Olympus: Olympus Workspace, Viewer
  • Third-Party: Capture One, DxO PhotoLab, ON1
  • Converters: Adobe DNG Converter, RawTherapee