How to Compress RAW Files on MacSave 70-90% storage space without losing quality
What Is RAW (Camera Raw Image)?
RAW is a general term for unprocessed image files captured directly from a camera sensor. Formats include CR2/CR3 (Canon), NEF (Nikon), ARW (Sony), RAF (Fujifilm), and DNG (Adobe). RAW files contain the full sensor data, giving photographers maximum flexibility in post-processing.
Why Are RAW Files So Large?
RAW files are large because they contain the complete, unprocessed sensor data at full bit depth (12-14 bits per channel vs 8 bits for JPG). A 50MP camera produces RAW files of 50-80MB each. A single day of professional shooting can generate 50-100GB of RAW files.
Typical RAW Compression Results
Before
20-80MB per photo
After
5-20MB per photo (as JPG/HEIF)
70-90%
Smaller
Compression Ratio
3:1 to 8:1
Codecs
Proprietary (CR2, NEF, ARW), DNG (Adobe)
How to Compress RAW Files on Mac (Step by Step)
Follow these steps to compress your RAW files using MediaOptim on macOS:
Open MediaOptim
Launch MediaOptim. It supports all major RAW formats including CR2, CR3, NEF, ARW, RAF, and DNG.
Import RAW files
Drag your RAW photo folders into the app. MediaOptim detects the camera and RAW format automatically.
Choose strategy
Select "Export to HEIF/JPG" for maximum savings, or "Convert to DNG" for lossless archival with moderate savings.
Process
MediaOptim processes RAW files with color-accurate rendering. Large collections may take time due to file sizes.
Manage originals
Once exported, review results. You can then archive or remove original RAW files to reclaim 70-90% of the space.
RAW Technical Details & Compression Tips
Best Quality Settings
Export edited RAWs to JPG quality 92-95 or HEIF quality 85-90 for storage. Keep original RAW files for important photos that may need re-editing. Use DNG for archival with lossless compression for 15-25% savings over proprietary RAW.
When to Convert vs Compress
After editing, always export to JPG or HEIF for viewing and sharing. Keep RAW originals only for photos you might want to re-edit. Convert old RAW files from completed projects to save massive amounts of space.
Technical Specifications
- Contains unprocessed sensor data at 12-14 bits per channel
- Common formats: CR2, CR3, NEF, ARW, RAF, ORF, DNG
- DNG with lossless compression saves 15-25% over proprietary RAW
- Lossy DNG compression saves 30-40% with minimal editing flexibility loss
- Exporting to JPG quality 95 saves 70-90% with excellent visual quality
Frequently Asked Questions
How do I compress RAW photos on Mac?
Convert edited RAW files to JPG (quality 92-95) or HEIF for 70-90% savings. For lossless compression, convert to DNG format which saves 15-25% while preserving full editing capability.
Should I delete RAW files after editing?
For important photos, keep the RAW original. For everyday shots, exporting to JPG or HEIF and deleting the RAW saves 70-90% space. MediaOptim makes this batch process easy.
What is the best way to archive RAW photos?
Convert to DNG (Adobe's open RAW format) with lossless compression. This saves 15-25% space, ensures long-term compatibility, and preserves full editing capability.
How much space do RAW files take?
A 50MP camera produces 50-80MB per RAW photo. A typical 1000-photo shoot generates 50-80GB. A year of regular shooting can accumulate 500GB-1TB of RAW files.
Can I batch convert RAW to JPG on Mac?
Yes. MediaOptim handles batch conversion of unlimited RAW files to JPG or HEIF, processing entire photo libraries at once.
Compress Your RAW Files Now
Save 70-90% on your RAW files. No quality loss. Everything stays on your Mac.
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