This page discusses the sensor that is used in the Leica M (Typ 240): a 24 Megapixels CMOS sensor built by the Belgian company CMOSIS. Since this sensor presents a departure from CCD sensors to a CMOS sensor for the M camera series, there were some debates in the photo forums about it. On this page, I collect a few technical data, available test results, and opinions on the sensor.
Here are the most important technical data for the Leica M's (Typ 240) sensor:
DxO published the Leica M (Typ 240) sensor test results at the end of March 2013. In this test, the Leica X Vario achieves a DxOMark score of 84 points. DxOMark's conclusion is: "An Overall Score of 84 ranks 8th for all full frame sensors on the DxOMark database placing the Leica M’s new 24-megapixel CMOS sensor in to the top ten (March 2013). ... Its individual category rankings are all down on 11th place however making it a good all rounder without a particular strong point."
Color discrimination (24 bits) and dynamic range (13.3 EV) are rated both quite OK for its class, but the Low-Light ISO performance (1860 ISO) seems to be behind the competition (although it is much better than the X Vario's performance).
Thus DxOMark concludes: "Despite a big step forward for image quality DxOMark Sensor Scores for the Leica M indicates the new 24-megapixel CMOS sensor remains a little behind the best full frame sensors available."
For details, see Leica M (Typ 240) sensor review: How does the new 24-megapixel CMOS sensor in Leica’s latest rangefinder perform? (DxO sensor rating) and the references below.
Imaging Resource (from Leica M 240 Impressions, Michael Reichmann): Image Quality. Let’s cut right to the chase. The M240 new CMOS sensor is brilliant. I mean that the way the British use the word; ie: terrific. I didn’t have an opportunity to directly compare images between it and an M9, but I have no reservations about any of the sensor’s major characteristics – colour rendition, dynamic range, high ISO and resolution. There are sensors that may score higher on tests, but for real-world photography it’s hard to find anything not to like about the new M’s sensor. Sean Reid sees some occasional banding at high ISO, but I see nothing to fuss me. I do see some IR contamination when very deep shadows are opened up, but the M isn’t alone in this regard, and I’m talking six stops or more below 18%. Reviewers whose opinion I respect seem to pretty much agree that this is a great sensor, or at least let’s say that I now agree with them.
To be continued...
In the Leica M (Type), Leica uses a new 24 Megapixels CMOS sensor built by CMOSIS that offers better low light performance, that is high ISO behavior that the CCD sensors in the preceding models (M9, M8). Overall, this new sensor does not seem to come quite up to the expaectations. In newer full-frame Models (Q, SL) Leica uses other sensors (or two variants of the same sensor).
In 2013, primarily with firmware update 184.108.40.206 (October 2013 - a year after the camera's announcement at Photokina 2012!), Leica improved the color and white balance behavior of the camera considerably, probably because it had more experience with this new sensor.
Below, I list references to dicussions of the sensor, sensor tests and other sensor-related stuff.