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Image Conversion

Convert MEF to JPEG — Free Online Converter

Convert Mamiya Raw Format (.mef) to Joint Photographic Experts Group (.jpeg) online for free. Fast, secure image conversion with no watermarks or regi...

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How to Convert

1

Upload your .mef file by dragging it into the upload area or clicking to browse.

2

Choose your output settings. The default settings work great for most files.

3

Click Convert and download your .jpg file when it's ready.

About MEF to JPG Conversion

JPEG is the universal photographic format, and converting Mamiya MEF RAW files to JPEG makes medium format photography accessible to everyone. Mamiya cameras like the 645AFD, 645DF, and systems with Phase One digital backs capture stunning detail at 22-80+ megapixels in 14-16 bit RAW data. JPEG compression transforms this into a shareable, printable photograph viewable on any device, platform, or service worldwide.

This conversion is the standard delivery format for commercial photography clients who need final images from medium format shoots. The RAW data is demosaiced, color-corrected using the camera's metadata, and compressed with JPEG's efficient DCT algorithm. The result balances excellent visual quality with practical file sizes suitable for email, web publishing, and photo printing.

Why Convert MEF to JPG?

Commercial clients, magazine editors, and advertising agencies typically receive final selects as JPEG files, even when the originals were shot on medium format. MEF files require specialized software (Capture One, select Lightroom versions) and are impractical for delivery — a single 60 MP MEF file can exceed 60 MB. JPEG delivery at high quality produces files of 5-15 MB that open instantly on any device.

Medium format photography's primary audience — fashion, beauty, commercial, and fine art clients — expects deliverables in universally compatible formats. JPEG at quality 90-95 preserves the remarkable detail and tonal range of medium format captures while making the files accessible in every application from email clients to layout software.

Common Use Cases

  • Deliver final selects from Mamiya 645DF+ commercial shoots to advertising clients in JPEG format
  • Create high-quality web-ready images from Phase One medium format captures for portfolio websites
  • Prepare Mamiya medium format photographs for magazine and publication submission in JPEG
  • Generate client review galleries from MEF studio sessions with high-quality JPEG previews
  • Convert MEF files for photo printing services that accept only JPEG uploads

How It Works

LibRaw (via Sharp) decodes the MEF file, interpreting the medium format sensor's Bayer pattern at 14-16 bit depth. Camera metadata — white balance, color matrix, black level, and optional lens profile corrections — is applied during demosaicing. The full-color image is then compressed using libjpeg-turbo's DCT algorithm. At quality 90-95, the JPEG preserves remarkable detail from the medium format sensor. EXIF metadata including camera model, lens, exposure settings, and capture date is mapped to the JPEG output.

Quality & Performance

JPEG at quality 90-95 preserves outstanding detail from medium format sensors. The DCT compression introduces minimal artifacts imperceptible at normal viewing, while reducing file sizes from 50-80 MB (MEF) to 5-15 MB (JPEG). The 14-16 bit RAW depth is reduced to 8-bit JPEG, losing the extreme shadow/highlight recovery range. For critical applications, the quality is more than sufficient for professional print production and portfolio display.

SHARP EngineFastMinimal Quality Loss

Device Compatibility

DeviceMEFJPG
Windows PCPartialPartial
macOSPartialPartial
iPhone/iPadPartialPartial
AndroidPartialPartial
LinuxPartialPartial
Web BrowserNoNo

Tips for Best Results

  • 1Use quality 90-95 for client delivery to preserve the full benefit of medium format resolution
  • 2Keep original MEF files as masters — they contain far more data than any JPEG can represent
  • 3For web portfolio galleries, quality 80-85 produces excellent results at more reasonable file sizes
  • 4Medium format JPEG files are large (5-15 MB) — consider WebP for web delivery at smaller sizes
  • 5Apply any retouching and color grading before converting to JPEG to avoid generation loss

MEF to JPEG is the standard delivery conversion for commercial medium format photography. High-quality JPEG preserves the remarkable detail of Mamiya sensors in a universally accessible format.

Frequently Asked Questions

Quality 90-95 is recommended for medium format delivery — it preserves the exceptional detail these sensors capture while producing practical file sizes. Quality 80-85 is acceptable for web use where file size matters more.
At quality 90, a 60 MP medium format capture produces a JPEG of approximately 10-15 MB. At quality 80, expect 5-8 MB. These are very large for JPEG but necessary to preserve the medium format detail.
Absolutely. Medium format JPEG at quality 90+ contains enough detail for billboard-sized prints. A 60 MP image prints at 20x15 inches at 300 DPI — sufficient for any commercial print application.
Camera body information, exposure settings, and capture date are preserved in EXIF. Mamiya-specific lens profiles and correction data may not transfer directly but are applied during the demosaicing process.
Never for professional medium format work. The RAW file preserves the full 14-16 bit sensor data, allowing recovery of highlights and shadows, white balance adjustment, and maximum quality output. Always shoot RAW and convert to JPEG for delivery.

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