The Google Photos blog, which is in fact the Picasa Blog, explained Picasa raw image support in 2008.
Picasa is not an image editor
Alexander Kunz describes why Picasa is little more than a raw image viewer, not an editor:
Picasa does NOT support every raw file. With each new model, camera vendors slightly tweak their raw format, even if the file extension is the same… The main reason to shoot raw is to stay in control in the conversion process
- How much contrast do you want?
- Do you want highlights?
- Want to keep every detail in the shadows?
But you can adjust these things in Picasa later, right?
No, not very well.
Picasa is an 8 bit program… edits work on 8 bit image data. But the main advantage of raw sensor data is that it contains 12 bit or even 14 bit depth and … more room for shadows and highlights – which you try to bring closer together when you manually convert a raw file… Picasa’s raw conversion is NOT manual. You have NO influence on the conversion. Picasa finds a raw file, it renders an 8 bit version out of that file, and that’s it. You’re not in control, and what you get is an automatic conversion of your raw data. One of the key advantages of shooting raw is lost.
Both posts mentioned above were written over two years ago. Has anything changed since then? Has Picasa improved its raw image support?
Again, the answer is no, not really. There haven’t been many changes in terms of processing. Sharpening can better controlled. However, the most significant issues, the manual conversion process and 8-bit character of Picasa as a program, have not changed at all.