I took a few shots with my D750 and 24-70 the other day, jpegs it turns out, at 12800 no less.
Impressive noise control, but not bitingly sharp and white balance is a little off.
Tonight I had the 15mm Leica on the Pen F and luckily my muse was handy. ISO 1600 this time, because the lens is faster.
Not a fair comparison I guess, but the Pen files are sharp and white balance is slightly more realistic.
After a pass through No Noise. The Pen F is probably my weakest 20mp camera noise wise, but has bags of clarity and nice character at higher ISO’s.
A couple of reasons for trying the 15mm on the Pen.
The aperture ring is problematic on a Panasonic. Nice idea, but really too light and hard to trust. It refuses to stay on “A” for more than a few shots and cannot be disengaged. On an Oly camera it just does not work, so problem solved.