I've received confirmation from sources at Panasonic that the Panasonic G5 uses the same sensor as the Panasonic GH2. Many have suspected this to be the case since the specifications for the G5 sensor indicate 18.3 MP total and 16.1MP effective, which is the same as the GH2. I actually received this information weeks ago but was reluctant to publish it as I had a hard time believing it to be true. The reason for the "oversized" 18MP sensor in the GH series is that those cameras have multi-aspect ratio sensors - ie, the 4:3, 3:2, and 16:9 output are cropped from an oversized sensor such that the diagonal angle of view is preserved in each case. In contrast, other Micro 4/3 cameras crop the 3:2 and 16:9 output from their 4:3 output such that the diagonal angle of view is reduced in 3:2 and 16:9. Looking at the file dimensions from the GH2 and G5, it's clear that the latter does not make use of a multi-aspect ratio sensor. GH2: [4:3] 4,608 x 3,456 [3:2] 4,752 x 3,168 [16:9] 4,976 x 2,800 G5: [4:3] 4,608 x 3,456 [3:2] 4,608 x 3,072 [16:9] 4,608 x 2,592 I've now learned that while the G5 does in fact use the same sensor as the GH2, the multi-aspect ratio feature of the sensor could not be included without compromising other improvements to the still and imaging performance which were achieved in conjunction with the new Venus VII FHD engine: Video now capable of 1,920 x 1,080, 60p (vs 30p with GH2) Still photography burst rate now 6fps (vs 5fps with GH2) AF speed improved on G5 compared with GH2 It was implied that there were other improvements, including some directly affecting, image quality which were made possible by leaving out multi-aspect ratio capability. The bottom line is that Panasonic chose to leave out multi-aspect capability in order to include other image quality and performance improvements that they felt would be more important to customers. Like the Olympus E-M5, the GH2/G5 uses a "digital" sensor, meaning the analog-to-digital conversion (ADC) takes place on the sensor. In contrast, an "analog" sensor like the one in the G3/GX1 sends analog information to an offboard ADC. A digital sensor will generally have a faster readout and slightly lower read noise, the latter of which explains the slightly better dynamic range of the GH2 and G5 as compared to G3 and GX1. As many here are aware, Vitaliy Kiselev has developed and released tools which allow us to hack Panasonic cameras, notably the GH1 and GH2, to remove firmware restrictions. The primary purpose of hacking these cameras has been to allow changing of video encoding parameters. In particular, increasing the video recording bit rate can significantly improve video quality. After learning about the G5 sensor, my first thought was whether Vitaliy might be able to unlock its multi-aspect capability. Presumably this would involve a number of tradeoffs as specified above, but I've no doubt that some adventurous G5 users would welcome the choice.