Solution
When the camera is set to [ ] or to one of the [SCN] shooting modes: [ ], [ ], [ ], [ ], the compression ratio is set to [ ] and cannot be changed.
Caution
[ ] and [ ] indicate different levels of image quality depending on the extent of compression. At the same size (number of pixels), [ ] offers higher image quality. Although [ ] images have slightly lower image quality, more fit on a memory card. Note that [S2]-size images are of [ ] quality.