This is a comparison of the per-pixel noise and optical qualities of the Canon 400D vs the Panasonic FZ50 with the same real focal length, and Av, and Tv values. The 400D is set to ISO 1600 to take advantage of the camera's high-ISO benefits. The FZ50 uses a horrible amplifier for ISO gains, which makes ISO 1600 noise more than 16x ISO 100 noise, so just to compare the sensors, I under-expose the FZ50 from ISO 100.

Despite the fact that the 400D image looks much softer, it is actually using the sharpest lens I have ever used at its sweet spot (Tamron 90mm Macro at f/4). That's because it has to be upsampled to be compared to the native FZ50.