@liork it's the same pixel count. GX8, Pen-F, E-M1 II and GH5, they all have a 5184 x 3888 pixel sensor. Panasonic saying 20.3MP and Olympus saying 20.4 is just a different in how they made the pixel approximation but both sensors have the exactly same pixel count.

Wow... I am kinda impressed with the "6K photo 30fps" mode for photography. 18 megapixel stills from the 6K photo mode not to shabby. Also I must say that the autofocus on the GH4 was really good so I can imagine how good it will be with the GH5. I am talking about AFS single point, point to point focusing. M/43 does not work for me in terms of photography but I am sure this camera will be great for all of the people that it does work for.

The first GH5 low light test I could find (in the second part of the video):

I am curious to see what type of improvement this is has in terms of lowlight ability. Personally speaking for me this was the biggest downfall for the GH4. The GH5 with 10bit 422 4K internally, .76 EVF/3,680 resolution, waveform monitor and vectorscope is a HUGE upgrade. The ability to have all of those features without carrying around an external recorder/monitor will sway a lot of people into purchasing the GH5.

There are couple of red flags though. The biggest one being that the firmware will come later on down the line. Wonder how much that will cost Cha-Ching $$$$$. I am also curious as to the the actual improvement in quality with the firmware update once all the hype settles down. I don't know maybe I am a bit pessimestic after all the hype with VLOG which IMO was a waste of time and just added more noise to the image after everything is said and done. Also look at the ALL-Intra on the GH4 was is it really that great all things considered?

All in all though seems like a great camera. Personally I wouldn't purchase one until after all of the firmware updates are done along with some real reviews of the camera. Until the firmware updates come seems like it is really not worth buying if you already have a GH4.

@EspenB GH5 sensor from Panasonic site: 17.3 x 13.0 mm, Total pixels 21.77 Megapixels, Camera effective pixels 20.30 Megapixels.

E M1 II: 17.4 x 13.0mm, Total Pixels 21.8 million, Effective Pixels 20.4 million

The Oly E-M1 Mark II clearly is a native 4/3 aspect sensor. The sensor in the GH5 is not.

Picture of Oly used sensor attached.

GH5 sensor may look bigger because it has 22Mpixel total and 20Mpixel used. I wonder If RAW photos can use 22Mpixel with some Raw program.

@Eno Yes, something fishy are going on!

Even in the presentation video the sensor seems wider than the GH4 sensor.

(Could be a fake creative render which takes liberties?)

The numers you list seem to indicate 1:1.4 aspect ratio.

I've downloaded the higher res GH5 front image (from Dpreview) and compared the sensor size with the Gh4.

Comparing the two different sensor sizes, I've approximately calculated the Gh5 sensor must be 19,185 mm in length and 13,735 mm in height.

@Vitaliy_Kiselev

Are you suggesting price cuts in the near future?

I was one of the first to receive a GH4 two years ago and had to send it in for repair for the "audio hiss" issue, so I'll wait a little while.

It has "my menu" for favorite menu items. Great!