Upgraded from the 7D to the 7DMkII last year and I noticed that on the large fine setting, the 18MP 7D creates JPEG files in the range of 6-8 MB averaging in the high sevens while the 20MP Mark II JPEG files are 4-7 MB averaging in the low sixes. Does anyone know how Canon tweaked its algorithm? Am I getting more photos on a card at the expense of image quality? Inquiring minds want to know.