ARW (Sony Alpha Raw)
ARW is Sony's proprietary raw image format used by Alpha mirrorless and DSLR cameras. It preserves the unprocessed sensor data with full dynamic range, allowing maximum flexibility in post-processing exposure, white balance, and color grading.
MIME Type
image/x-sony-arw
Type
Binary
Compression
Lossless
Advantages
- + Maximum image quality with full sensor dynamic range
- + Non-destructive editing — original data is preserved
- + 12-14 bit color depth for advanced color grading
Disadvantages
- − Proprietary format requiring Sony-compatible raw processors
- − Large file sizes (20-60 MB per image depending on resolution)
- − Not viewable in web browsers — requires conversion
When to Use .ARW
ARW files come from Sony cameras; convert to DNG for archival or develop in Lightroom/Capture One for final output.
Technical Details
ARW files contain raw Bayer-pattern sensor data with 12-14 bit depth. Metadata includes EXIF, Sony MakerNote tags, and embedded JPEG previews. Newer cameras use lossless or lossy compressed ARW variants.
History
Sony introduced the ARW format with the Alpha series cameras in 2006. It is based on the TIFF/EP standard with Sony-specific extensions for sensor metadata and compression.