Shot in RAW on a Panasonic LUMIX and now stuck with .RW2 files nothing wants to open? Windows does not read RW2 out of the box, so you either hunt down an old camera codec or upload the file somewhere. RW2 is Panasonic's proprietary RAW format, a TIFF-based container holding 12-bit or 14-bit sensor data, which is why a single frame is often over 20 MB. This converter opens the RW2 straight away and writes a normal JPG you can open and share anywhere.