Raw Compression and bit depth on the NEX-7

There are 2 fundamental kinds of compression: Lossy & Lossless. An example of a Lossless type of compression is a ZIP file - when you expand it you get the exact same digital file as the original, before it was compressed. Nothing is lost. JPG is an example of Lossy compression - depending on the JPG quality you select, it makes compromises on things like color and when it is decompressed, the digital file is different than the original. RAW files are compressed to save space, but the compression used is Lossless. When decompressed, you have the original digital data file, but most processors will then convert that into a JPG, or other format, and that other format may be lossy. However, when working on a RAW file in a program like ACR, you're working on the expanded original data file.

The only uncompressed format that I am aware of is TIFF, and if you compare a RAW file to its TIFF equivalent, you'll see that the TIFF is much larger.