ERF to Markua Converter
FileFlip converts ERF to Markua entirely inside your browser, using ImageMagick, MuPDF and Pandoc 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 Markua?#
- 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 Markua and the conversion starts on its own. FileFlip downloads 79.9 MB of WebAssembly the first time and nothing after that, then runs ImageMagick, MuPDF and Pandoc on your own machine.
- Save the Markua file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting ERF to Markua lose quality?#
No. The ERF picture is placed into the Markua document at its full resolution, so every pixel reaches it intact. What you give up is that it becomes a picture inside a document rather than text.
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 Markua actually does to the file#
Converting ERF to Markua runs on ImageMagick, MuPDF and Pandoc, downloads 79.9 MB of WebAssembly the first time and nothing after that, places the picture into the document at full resolution.
| Engine | ImageMagick, MuPDF and Pandoc |
|---|---|
| Conversion path | 3 steps: ERF → PNG → HTML → Markua |
| Downloaded to your browser | 79.9 MB, once, then cached by your browser |
| Quality | Pixels preserved |
| 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
- the picture is placed in the document as a picture; no text is recognised out of it
- the file passes through HTML on the way, so anything HTML cannot express does not survive
- 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 Markua file?#
A MARKUA file holds Markua, Leanpub's Markdown dialect for writing books and courses, adding parts, chapters, asides, quizzes and other publishing structure that plain Markdown has no syntax for.
Write in Markua when the book or course is being authored and published on Leanpub.
Convert a manuscript to Markua when importing it into Leanpub from another format, since Leanpub's build pipeline is built around it.
ERF to Markua 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 Markua file used for?
A Markua file holds the source of a book or course written for Leanpub, using Markua, the publishing platform's own Markdown dialect. Leanpub builds the finished EPUB, PDF and MOBI editions directly from this source.