ERF to SUN Converter
FileFlip converts ERF to SUN entirely inside your browser, using ImageMagick compiled to WebAssembly. The file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. That means no file-size limit, no queue and no account.
How do I convert an ERF file to SUN?#
- Drop your ERF file onto the converter at the top of this page, or click it to pick one from your computer. You can add as many as you like.
- Leave the target set to SUN and the conversion starts on its own. FileFlip downloads 14.1 MB of WebAssembly the first time and nothing after that, then runs ImageMagick on your own machine.
- Save the SUN file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting ERF to SUN lose quality?#
No. Converting ERF to SUN writes the data out again without discarding any of it, so nothing that was in the ERF file is lost on the way. What changes is the size of the file, not what is inside it.
Is it safe to convert ERF files online?#
Yes, because nothing is uploaded. FileFlip converts ERF files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What ERF to SUN actually does to the file#
Converting ERF to SUN runs on ImageMagick, downloads 14.1 MB of WebAssembly the first time and nothing after that, writes the data out again without discarding any of it.
| Engine | ImageMagick |
|---|---|
| Conversion path | One step: ERF → SUN |
| Downloaded to your browser | 14.1 MB, once, then cached by your browser |
| Quality | Lossless |
| You get back | One file |
| Where it runs | In a background worker, so the page stays responsive |
Worth knowing before you start:
- camera raw is demosaiced with ImageMagick's defaults, which will not match the camera's own rendering
- some cameras write lossily compressed raw, so the source is not always a complete sensor record
What is an ERF file?#
An ERF file holds the raw color filter array data from an Epson R-D1 or R-D1s digital rangefinder, wrapped in the TIFF/EP structure alongside an embedded thumbnail and Exif metadata.
Keep a file as ERF only if it is an original R-D1 or R-D1s capture you are archiving unchanged.
Convert ERF to DNG or TIFF for long-term storage or editing in current software, since the only two cameras that ever wrote the format stopped being made years ago.
What is a SUN file?#
A SUN file is a Sun Raster bitmap, the same raw framebuffer image format Sun Microsystems shipped on SunOS workstations, saved under the alternate .sun extension some raster-image tools use in place of the identical .ras.
Recognise a .sun file as a Sun Raster image if it turns up alongside .ras files from the same legacy Solaris export or archive.
Convert SUN to PNG or TIFF for any modern use, since the .sun extension gets even less software recognition than .ras.
ERF to SUN questions people ask#
What camera shot this ERF file?
ERF files come from only two cameras, the Epson R-D1 rangefinder released in 2004 and its 2006 update the R-D1s. Epson built the R-D1 with Cosina, pairing a Leica M-mount rangefinder body with Epson's own sensor electronics and image processing.
Can I still open an ERF file?
Yes. ERF files open in RawTherapee, darktable and digiKam through the libopenraw decoding library, and ExifTool reads their embedded Exif metadata. Epson never updated its own raw software after leaving the camera market, so a current raw processor is the practical option.
What should I convert ERF files to?
Converting ERF to DNG or TIFF is worth doing for long-term storage, since Epson exited the camera body business in 2014 and no software vendor has a reason to add new support for a format tied to two discontinued cameras.
What is a SUN file?
A SUN file is a Sun Raster bitmap, the simple framebuffer image format Sun Microsystems used on SunOS and Solaris workstations, identified by a fixed magic number at the start of the file rather than by its extension.