I'd be pleased for any help on this.

I'm not totally new to Digital photography but am bemused by a setting on my S95. I have set the camera to max file size/quality on Jpeg only (i.e not RAW + Jpeg) but although it's said to take 10Mg images I rarely get a file larger than 1 mg currently, mostly far smaller even in strong sunlight. Strangley, when I used the camera for the first few weeks it usually took images around 2.0-2.5 Mg, never higher. It's true I've played with the settings a lot but I can't figure out why files are so small. Am I limiting the quality I can achive with the S95? or is it just packing lots of detail in a small file size ? Any ideas on settings are very welcome.