ARW to CR2 Converter

Encoding: the ARW uses Sony's lossy compressed raw, uncompressed (since the A7R II) or lossless compressed (since the A1); CR2 uses lossless JPEG-compressed sensor data, cut into vertical slices, and the download is a Linear DNG: demosaiced 8-bit RGB with the colour matrices raw editors need.

Bit depth: 12 or 14 bits per channel in the ARW; CR2 allows 12 or 14 bits per channel, and the DNG written here has 8 bits per channel, linearised. The sensor's 12 or 14 bits are not used: the 8-bit camera preview is converted.

Colour: camera RGB from a Bayer mosaic in the ARW; CR2 supports camera RGB from a Bayer mosaic, with the Picture Style recorded in the maker notes, written here as 8-bit sRGB.

Metadata: the ARW can carry EXIF, Sony maker notes, a thumbnail and a full-size JPEG; CR2 can carry EXIF, Canon maker notes (Picture Style, lens, focus points) and the embedded previews, but nothing is copied across.

ARW is the raw format of Sony Alpha, RX and Cyber-shot cameras. It stores the sensor data (compressed, uncompressed or lossless compressed, depending on the model) with a full-size JPEG preview.

ARW is TIFF-based: the first directory carries EXIF and Sony's JPEG preview and the sensor data sits in a sub-directory. In Sony's classic compressed raw each block of 16 same-colour pixels keeps an 11-bit maximum and minimum plus 7-bit steps for the rest, which can leave artefacts beside high-contrast edges.

ARW files usually come from Sony Alpha mirrorless and SLT cameras, RX compacts and some Cyber-shot models.

CR2 is the raw format of Canon EOS cameras from 2004 until CR3 replaced it in 2018. It holds the sensor's 12 or 14-bit readings, losslessly compressed, plus a large JPEG preview rendered with the camera's Picture Style.

CR2 is TIFF-based: the TIFF header is followed by the letters 'CR' and version 2.0, then four image directories: a large JPEG preview with the EXIF block, a 160×120 thumbnail, a small uncompressed RGB image, and the sensor data as lossless JPEG cut into vertical slices.

CR2 files come from Canon EOS DSLRs made from 2004 to 2018, such as the 5D Mark II and III, 6D, 7D and the Rebel series.

Forms and workflows that ask for CR2 usually feed a raw editor, and each of those opens DNG as well, so the DNG can take the CR2's place. Keep the ARW if you only need to view or share the picture.

What CR2 offers when it comes straight from the camera: Large embedded JPEG rendered with the camera's Picture Style; Lossless 12 or 14-bit sensor data; Widely supported after fourteen years of Canon DSLRs. Its drawbacks: Replaced by CR3 in 2018, so current Canon bodies no longer write it; 20 to 50 MB per photo; Sliced lossless JPEG data that only raw decoders can read.