ORF to PNG Converter

ORF to PNG: What This Page Covers, and Which Preset You Actually Want

An ORF is the undeveloped raw file an Olympus or OM System camera writes — a TIFF-structured container whose signature bytes (MMOR, IIRO, or IIRS) are deliberately non-standard, which is why no browser and few photo viewers will open it. PNG is the opposite: a finished raster image that opens everywhere and, in its full form, stores every pixel exactly. But "PNG" does not automatically mean "lossless" on this page, and the difference is one dropdown. This walk-through explains which Quality Preset gives you a true-colour render, which controls look useful but are inert for a raw source, and when PNG is the wrong target altogether. Files are uploaded over an encrypted connection, processed on our servers, and deleted automatically after a few hours — no sign-up, no watermark, never shared or made public.

How to Convert ORF to PNG

1. Upload Your ORF File: Drag your .orf files onto the page or click "+ Add Files". Olympus raws are large, so upload dominates the wait; queue several and they convert with one shared set of settings.
2. Set the Quality Preset to Highest for a True-Colour PNG: This is the decision that matters. Under Image Compression, Quality Preset is set to Very High (Recommended) — but only the Highest rung writes a full-colour PNG. Every other rung sends the image through a palette quantiser. The next section shows exactly what each one produces.
3. Adjust the Resolution or Target a Size: Image resolution is on "Keep original", which preserves your camera's full pixel dimensions; a percentage, a height preset, or an exact Width x Height will scale it down. Alternatively switch Image Compression to "Specific file size" and name a target in bytes, kilobytes, or megabytes, leaving Auto Scale on.
4. Convert and Download: Click Convert and save the PNG. No sign-up, no watermark.

Walk-through: The Quality Preset Decides Whether Your PNG Is True-Colour

PNG output here runs down two different code paths, and the Quality Preset picks between them. On the Highest rung the image is written straight out by the PNG encoder and nothing else touches it. On every other rung the rendered image is passed to pngquant, a lossy palette quantiser, before it becomes the file you download.

That matters more for a raw file than for almost any other source. Your Olympus sensor recorded 12 bits per channel; the default preset delivers an image with a maximum of 256 distinct colours in the whole frame. On a smooth sky or a portrait's skin tones the banding is visible. We reproduced the quantiser step on its own to confirm the behaviour: a true-colour test image containing nearly 400,000 distinct colours came back as a 256-colour palette image, with no colour count requested. If you are converting an ORF because you want a faithful render, set Quality Preset to Highest.

Controls That Render Here But Do Nothing for a Raw Source

Three controls on this page look like they should help and do not, because of how the raw-source path is wired.

• Colors — the palette-size dropdown with its 2-to-256 entries and the Dither switch. For a source that is not already a PNG, no colour count is passed to the quantiser at all, so it falls back to its own 256-colour default no matter what you pick.
• Compression speed — the 1-to-10 dropdown. The value is read and then overwritten with the slowest, highest-quality setting immediately before the quantiser runs, so the dropdown cannot change anything.
• Compression level — the 1-to-10 dropdown. On the Highest preset it is replaced with maximum compression. On every other preset the intermediate file it affects is discarded when the quantiser writes the final PNG. Either way it does not determine the file you download.

None of these are hazards — they simply will not repay the time you spend on them. The Quality Preset and Image resolution are the two controls that genuinely change the output here.

ORF vs PNG

When This Doesn't Work

PNG is a poor fit for a photograph you simply want to send someone: on the Highest preset a full-resolution Olympus render is frequently larger than the raw it came from, and on any other preset it is a 256-colour image. For sharing, ORF to JPG gives a much smaller file with far better colour fidelity at any sensible quality. For an editing master, ORF to TIFF set to the LZW compression type carries a lossless image with no palette step anywhere in the path. PNG earns its place when you need a lossless 8-bit render, an alpha channel for compositing, or a format a specific tool insists on — and in those cases, use the Highest preset. This converter also renders with neutral defaults rather than replacing a raw editor: recovering blown highlights or correcting a strong colour cast should happen on the ORF first.

Frequently Asked Questions

Is the PNG I get from an ORF actually lossless?

Only on the Highest Quality Preset. That rung writes the render straight out through the PNG encoder with no quantisation. Every other rung — including the default, Very High — routes the image through pngquant first, which reduces it to a 256-colour palette. PNG the format is lossless; the pipeline in front of it on this page is not, unless you choose Highest.

Why does the Colors dropdown not change my output?

Because for a source that is not already a PNG, no colour count is handed to the quantiser. It runs with its own default of 256 colours, so selecting 128, 32, or 2 in the dropdown makes no difference to an ORF conversion. The Dither switch beside it is in the same position. To reduce colours deliberately, quantise the finished PNG in an image editor instead.

What do the Compression speed and Compression level dropdowns do here?

Neither reaches the file you download. Compression speed is overwritten with the slowest, highest-quality setting just before the quantiser runs. Compression level is forced to maximum on the Highest preset, and on the other presets it only affects an intermediate file that is thrown away when the quantiser writes the final PNG. Leave both alone.

Should I convert my Olympus raw to PNG or to JPEG?

JPEG for almost every practical purpose — sharing, email, web, print orders — because it keeps full colour and produces a far smaller file. Choose PNG when you specifically need a lossless 8-bit render (set Highest), an alpha channel, or a format a particular tool demands. For a 20-megapixel frame the difference is stark: a Highest-preset PNG can exceed the size of the raw file it was made from, while a quality-95 JPEG lands in single-digit megabytes.

Does the PNG keep the 12 bits per channel my camera recorded?

No. The raw's extra bits are editing headroom, and they are spent the moment the file is developed into a finished image. On the Highest preset you get a true-colour render of that development; on any other preset you get an 8-bit palette image. Either way the ability to recover a blown sky or re-set white balance lives only in the original .orf, so keep it.

What pixel dimensions will the PNG have?

Your camera's full frame, as long as Image resolution stays on "Keep original" — 5184 x 3888 from a 20-megapixel OM System body, 4608 x 3456 from a 16-megapixel Four Thirds body. If the result comes out smaller than expected, check that the resolution group has not been switched to a percentage or a height preset.

Why can't Windows, macOS, or my browser open the ORF directly?

ORF is a TIFF-derived container that replaces the standard TIFF signature with Olympus's own bytes, so generic viewers reject it on sight. Beyond that, raw files hold undemosaiced sensor data that has to be interpreted with camera-specific knowledge before there is any viewable picture at all. Converting here does that interpretation on our servers, so nothing needs installing on your machine.

What happens to my ORF and the PNG after conversion?

Both arrive and leave together: your file is uploaded over an encrypted connection, processed on our servers, and deleted automatically after a few hours along with the output. There is no account to create, nothing is watermarked, and your photos are never shared or made public. If you want the finished PNG smaller, run it through compress PNG; the ORF converter hub lists every other target.