RW2 to PNG Converter

What is RW2 to PNG conversion?

RW2 to PNG conversion transforms Panasonic Lumix RAW image files into the universally supported Portable Network Graphics format. RW2, formally known as Panasonic Raw v2, is the proprietary RAW container used by all Lumix mirrorless cameras: the full-frame S series (S1, S1R, S1H, S5, S5 II, S5 IIX), the Micro Four Thirds GH and G lines (GH4, GH5, GH5S, GH6, GH7, G9, G9 II), and enthusiast compacts such as the LX100 II.

Technically, RW2 is derived from the TIFF specification, but Panasonic uses its own magic number 0x55 in the file header to distinguish RW2 from standard TIFF (which uses 0x2A). The file contains unprocessed 12-bit or 14-bit photodiode readings from the sensor, a full EXIF block, Panasonic Maker Notes with shooting parameters such as Photo Style and V-Log settings, and an embedded JPEG preview used for fast thumbnails.

PNG is an open raster graphics standard published in 1996 as a replacement for the aging GIF format. It uses the DEFLATE algorithm (the same one used by ZIP archives) to compress image data losslessly, preserving every pixel value with bit-exact fidelity. PNG supports 8-bit and 16-bit colour depth per channel, full 8-bit alpha transparency, and embedded ICC colour profiles. It is rendered natively by every browser, operating system, and image editor without additional codecs.

Technical comparison: RW2 vs PNG

File structure and data type

RW2 is a TIFF-derived container holding several sections:

• RAW Image Data - unprocessed photodiode readings at 12 or 14 bits per channel (4,096 or 16,384 brightness levels).
• Embedded JPEG Preview - a reduced-resolution JPEG for fast viewing on the camera's LCD and in file browsers.
• EXIF Metadata - shutter speed, aperture, ISO, focal length, camera model (Lumix S5 II, GH6, S1R, etc.), and lens model (Panasonic Lumix S, Leica DG, Sigma Art L-Mount).
• Panasonic Maker Notes - proprietary fields such as Photo Style, Cinelike D, V-Log, autofocus point data, and vignette corrections.

The defining feature of RW2 is the magic number 0x55 in the file header, which distinguishes it from standard TIFF (0x2A) and from competing RAW formats: CR2 (Canon), NEF (Nikon), ARW (Sony), and ORF (Olympus).

PNG uses a chunked streaming structure. Key chunks include:

• IHDR - width, height, colour depth, and colour type.
• IDAT - the image data compressed with DEFLATE.
• iCCP - embedded ICC colour profile.
• tRNS - transparency data for indexed and greyscale images.
• gAMA - the gamma value for correct brightness interpretation.
• pHYs - physical resolution in DPI.

Colour depth and dynamic range

The Lumix S1R with its 47-megapixel full-frame sensor and the Lumix S1H with its 24-megapixel video-oriented sensor produce RW2 files with substantial editing latitude. Saving the result as an 8-bit PNG reduces that latitude significantly - something to keep in mind when choosing the output bit depth.

File size comparison

Paradoxically, an 8-bit PNG is typically 2-3 times larger than the 14-bit RW2 it was created from. The reason is that RW2 stores one colour channel per pixel (Bayer pattern), while PNG stores three full RGB channels per pixel. Even with lossless DEFLATE compression, the data volume exceeds the RAW Bayer payload. For a 47-megapixel Lumix S1R frame, PNG can occupy 100-150 MB.

Platform compatibility

When to convert RW2 to PNG

Handing off processed images for further editing

When a photographer captures on the Lumix S5 II, processes the RW2 in RawTherapee or Capture One, and then hands the result to a designer or retoucher for finishing in Photoshop, PNG is the ideal intermediate format. It preserves lossless quality, introduces no compression artifacts, and is accepted by every image editor.

Images with transparency

Product photography on the Lumix GH6 for e-commerce often involves background removal. Once the background has been cut, PNG is the only widely supported format that preserves the alpha channel correctly. JPEG has no transparency at all, and WebP is supported but still not accepted everywhere.

Screenshots of camera menus or editing software

Videographers working on the Panasonic GH7 often publish workflow articles showing camera menus, V-Log settings, Cinelike D profiles, and editing software like DaVinci Resolve. RW2 frames of camera screens converted to PNG retain the sharpness of text and icons that JPEG compression would blur.

Archiving final retouched versions

After completing a full retouching cycle on wedding photos shot with the Lumix S5 IIX, many photographers store the final version as PNG for long-term reference. The lossless compression guarantees that years later the image opens exactly as the author created it, without accumulated artifacts from accidental re-saves.

Large-format printing through professional services

While TIFF remains the gold standard for print shops, many modern photo print services now accept PNG. For canvas prints up to 80x120 cm from 47-megapixel Lumix S1R frames, PNG provides sufficient accuracy without forcing you to work in TIFF.

Advantages of PNG as a destination for RW2

Lossless compression

PNG uses DEFLATE - a lossless algorithm that guarantees bit-exact reconstruction. This means:

• No block artifacts - unlike JPEG, PNG does not divide images into 8x8 blocks and does not create the characteristic boundary patterns.
• Preserved sharp edges - text, graphics, and architectural details stay crisp without halos.
• Unlimited re-saves - no matter how many times you open and save a PNG, quality does not degrade.

For photographers using Lumix for hybrid video and stills work, PNG is especially valuable when adding text overlays to frames for social media without quality loss.

Universal compatibility

PNG has been supported at the operating system level since the late 1990s. Every browser (Chrome, Firefox, Safari, Edge, Opera), every image editor (from Microsoft Paint to Adobe Photoshop), and every office suite (Microsoft Office, LibreOffice, Google Workspace) opens PNG without additional codecs.

8-bit alpha transparency

PNG supports a true 8-bit alpha channel with 256 transparency levels per pixel. This enables:

• Cut-out product images for marketplace catalogues with transparent backgrounds.
• Logo and watermark overlays with smooth transparency gradients.
• Composite layouts from multiple Lumix frames with overlapping regions.
• Web graphics with anti-aliased edges and soft shadows.

RW2 does not support transparency, so any compositing workflow requires conversion to PNG (or TIFF, or WebP).

Accurate colour reproduction through metadata

PNG carries colour profile information in the iCCP chunk, ensuring consistent rendering across monitors:

• Embedded ICC profile - sRGB, Adobe RGB, ProPhoto RGB.
• gAMA chunk - the gamma value for correct brightness interpretation.
• cHRM chunk - chromaticity coordinates of the primary colours.

This matters for advertising and product photography where colour accuracy is critical.

Best RW2 candidates for PNG conversion

Fully processed final versions

When the RW2 file has already passed through a complete processing cycle in a RAW converter (SILKYPIX, Lightroom, Capture One, RawTherapee), this stage typically includes:

• Corrected white balance - removing colour casts from mixed lighting.
• Adjusted exposure - recovering shadows and highlights within the Lumix sensor's dynamic range.
• Applied tone curve - dialling in contrast and saturation.
• Noise reduction - especially important for high-ISO shots from Dual Native ISO sensors in the GH5S, GH6, and S5 II.
• Corrected distortion and chromatic aberration - based on the lens profile (Panasonic Lumix S Pro, Leica DG, Sigma Art L-Mount).

Converting to PNG locks in the processing result in lossless form.

Images for online galleries and portfolios

PNG delivers the maximum achievable quality for 8-bit raster output, without JPEG artifacts. This matters for:

• Wedding portfolios - capturing dress lace texture and subtle gradients in Lumix S5 IIX frames.
• Architecture and interior shoots - where line accuracy and absence of compression halos matter.
• Black-and-white work - where JPEG artifacts in smooth tonal transitions become especially noticeable.

Background-removed product shots

Lumix GH6 with Leica DG lenses is a popular product photography setup. After background removal in a RAW converter or Photoshop, the result is saved as PNG for direct upload to marketplace product listings.

Intermediate files for multi-step editing

PNG is the ideal intermediate format for multi-stage processing: every save and re-open preserves quality. This matters for compositing, collages, and skin retouching of portraits shot on the Lumix S1H.

Limitations and recommendations

One-way conversion

Converting RW2 to PNG is irreversible. The 14-bit linear sensor data with up to 14 stops of dynamic range is reduced to 8-bit representation with about 8 stops. Subtle gradients in shadows and highlights are quantized and lost. White balance and tone curve are baked in, and further correction accumulates artifacts.

Recommendation: Always preserve original RW2 files. Convert to PNG only for specific tasks (handoff to a designer, publication, printing) and keep the RAW archive available for potential reprocessing with improved algorithms in the future.

File size increase

PNG takes significantly more space than the source RW2:

• RW2 (24 MP, Lumix S5 II) - 25 MB.
• PNG (the same photo after conversion) - 60-80 MB.
• RW2 (47 MP, Lumix S1R) - 50 MB.
• PNG (after conversion) - 100-150 MB.

For storing large archives this is significant. A thousand photos in PNG require 60-100 GB versus 25-30 GB in RW2.

Recommendation: For archiving and web publishing consider JPG at quality 90-95 - visually indistinguishable from PNG at 5-10 times smaller file size.

Social media re-encodes anyway

Instagram, Facebook, Threads, and similar platforms automatically transcode any uploaded PNG to JPEG, negating the lossless advantage. For social posts it is more efficient to upload high-quality JPG directly.

Basic decoding limitations

This service performs basic RW2 decoding with default processing parameters: white balance is taken from the camera metadata as recorded at capture time, standard sRGB gamma correction is applied, and demosaicing runs automatically. White balance adjustment, exposure compensation, highlight and shadow recovery, tone curves, Cinelike D and V-Log profiles, and noise reduction are not available. For full RAW processing with control over all parameters, use specialized software: Adobe Lightroom, Capture One, RawTherapee, or SILKYPIX (including the free SILKYPIX Developer Studio for Panasonic Lumix users). This service is suitable for quick conversion of RW2 to standard raster PNG when in-camera processing is acceptable or further editing is not required.