The Leica M does very good video with a codec that allows serious grading.
You can see examples on my site. VimeoPro.com/goff/alps.
However the camera has been criticised for lacking some essential features for serious videography.
For example there is no XLR socket with phantom power for an external microphone.
To get round that I use a Røde videomic plugged into the Leica stereo mic accessory,
although that means I cannot use the EVF.
The camera's visual sound monitoring is excellent,
but there is no headphone socket to monitor the recording.
More important, there is no way to extract raw video data, even though 4K should be possible.
What is needed is an HDMI socket, to connect with an external recorder like the Atomos Shogun.
If these omissions were fixed the Leica M could challenge the Sony A7s.
The sensor and manual lenses are ideal for videographers (who seldom use autofocus).
I have heard a rumour that Leica are developing a new "Videography grip",
With HDMI, XLR, headphone socket, etc. and a sufficient bit rate for high quality 4K on an external recorder.
Can anyone comment on this rumour?