Your files stay on your Mac.
Mamiya RAW (.mef) is the proprietary raw image format captured by Mamiya medium-format digital backs, storing full unprocessed sensor data at native resolution. Convertessa reads MEF files directly on your Mac and converts them to AVIF, JPG, PNG, TIFF, or WebP — no upload, no cloud, no account required. Drop a single file or an entire folder and every MEF inside is converted in one pass.
Drag one MEF file into Convertessa, or drop a whole folder to queue every Mamiya RAW image at once.
Choose AVIF, JPG, PNG, TIFF, or WebP from the output list. Convertessa preserves the original resolution and strips embedded EXIF metadata from every output file.
Click Convert. All processing happens locally on your machine; nothing is sent to any server.
Images, audio, video, documents, archives and eBooks — all converted natively, right on your Mac.
Pick a format you have — see everything Convertessa can turn it into.
Convert hundreds of files at once with per-type group defaults and individual overrides.
First-class support for HEIC, AVIF and WebP — encode and decode, both ways. Read JPEG XL and a dozen more modern formats too.
Drop files anywhere on the window. Native, instant, and exactly what you’d expect on a Mac.
Dial in compression, resolution and bitrate. Keep originals pristine or shrink for sharing.
Never overwrite a file by accident. Convertessa appends safe suffixes automatically.
Every job is logged locally. Re-run a previous conversion or revisit recent outputs in a click.
Bundle your converted files straight into a single ZIP, TAR or 7z — packaged and ready to share the moment a job finishes.
Right-click any file in Finder and choose Convert. A Quick Action handles it on the spot — no need to open the app first.
Shrink Convertessa to a tidy mini window that tucks into a corner — just a drop zone and a format picker for quick, one-off conversions.
No cloud. No account. No upload. Every conversion happens entirely on-device, using the power already in your Mac. What you convert is nobody’s business but yours.
Script conversions, wire them into your build, or batch a folder from the terminal. The same engine, no GUI required.
Read the full CLI documentation →Shrink Convertessa down to a small, focused window — drop, convert, done, with your recent conversions one click away.
macOS 14+ · Apple Silicon & Intel
New formats, new features, and fixes — every release, on the record.
The .mef format is used by Mamiya digital backs, including the ZD and DM series. Drop a file into Convertessa to confirm compatibility with your specific model.
Yes. EXIF and other embedded metadata — including GPS coordinates and camera details — are stripped from the output image during conversion.
Yes. Drop a folder onto Convertessa or run convertessa ./folder/ --to jpg in the terminal. Every .mef file inside the folder is converted in a single batch.