I am trying to estimate the well capacity of the MOS in the Cannon PowerShot G1X.

I have read to expect that the fill capacity of an MOS is of the order of 1000 to 2000 x the area in Sq microns.

I am guessing that for the G1X sensor of the order of 200 sq mm and ~14 x10^6 pixels the area of

one MOS is of the order of 14 or 15 sq microns . If the well capacity is 1000 to 2000 times the MOS area this would yield a well capacity for the MOS of the order of between 15000 and 30000 , which corresponds to between 14 and 15 bits.

Furthermore the system gain (electrons/Analogue to Digital Units) would reduce the number of stored bits

by 10 or more..

Since raw images from the G1x of 16 bits my estimation of the well capacity seems much too small

Can anyone help me to understand what is wrong with my thinking?