Leica M10 Monochrom vs Leica M10-R: Snowy Mountainside

A monochrome sensor forfeits a lot of flexibility in the name of tonality and sharpness. Given the black-dot pimples and sensor bifurcation issues of the Leica M10 Monochrom, the win on tonality is less than clean, so how much does the M10M monochrome sensor buy in terms of sharpness?

This page compares the detail capture of the Leica M10-R to the Leica M10 Monochrom at f/4, f/5.6, f/8. The M10R is presented both in color and in a black and white conversion. Commentary on noise, tonality, tonal differentiation and detail capture.

Leica M10 Monochrom vs Leica M10-R: Snowy Mountainside

Includes images at f/4, f/5.6, f/8 at up to full resolution, plus crops.

CLICK TO VIEW: Leica M10-R/M10m system

Snowy Mountainside

Leica 28mm f/1.4 Summilux-M ASPH Aperture Series: Waning Sun on Aspen Winter Wonderland, Lundy Canyon (Leica M10 Monochrom)

This series from f/1.4 through f/11 examines total imaging performance of the Leica 28mm f/1.4 Summilux-M ASPH. Sharpness near-to-far and across-the-field along with field curvature, focus shift and general imaging performance.

Of particular interest here is showing how to focus for a scene like this so as to achieve peak total sharpness given the field curvature and focus shift behaviors.

Leica 28mm f/1.4 Summilux-M ASPH Aperture Series: Waning Sun on Aspen Winter Wonderland

Includes images from f/1.4 through f/11 at up to full resolution, plus crops.

Overall I’m really pleased with this series—this is exactly the kind of subject that sings in black and white—color would have only been a distraction and raw conversion headache. But sadly (for me), the black-dot pimple problem pervades the fine details of the fine aspen branches. My finest images from this trip are all mangled by this unacceptable image quality defect.

CLICK TO VIEW: Leica M10-R/M10m system

Waning Sun on Aspen Winter Wonderland

f4 @ 1/1000 sec, ISO 160; 2020-12-18 13:59:59
Leica M10 Monochrom + Leica 28mm f/1.4 Summilux-M ASPH + filter B+W 090 Red
ENV: Lundy Canyon, altitude 8100 ft / 2469 m, 28°F / -2°C
RAW: vignetting corrected, push 0.5 stops, +100 Shadows, +15 Clarity, +20 Texture, USM {4,50,0}

[low-res image for bot]

Black Dots in White Spots 'Pimples': is Leica 'Cooking' the Raw Data with Acutance-Enhancing Imaging Pipeline? (CONFIRMED by a reader, also REPLICATED with Leica M10-R)

Update: I’ve confirmed this issue using DNGs from a reader, see comment from Brian K that follows near end of post. I had previously looked at quite a few images from his camera and not seen the issue. But with the right subject, the pimples are there in all their ugliness. No prescription yet for how to generate them, but clearly relates to textural detail of sufficient micro contrast. My working theory of Leica oversalting the soup remains top contender. Bittersweet for many fine images I made, all my shooting involved desert and mountain areas, perfect for the manifestation of this ugly image quality bug.

Black-dot-in-white-spot pimples
as displayed by RawDigger

Update 2: A/B comparison of the Leica M10-R to the M10M shows that the same issue exists on the Leica M10-R. The demosaicing process makes it a bit harder to see, but an A/B comparison with the same scene shows exactly the same black-dot pimples in exactly the same subject matter locations. This implies that the same raw-file manipulation is going on with both. Presumably, the underlying sensor technology is identical, with the color sensor differing only in its color filter array.

Update 3: RawDigger shows the pimples too, so that makes it definitely an issue with the DNG file, not a raw converter issue. Besides, back in 2015 with the Leica M Monochrom Typ 246 with the same issue, both ACR and CaptureOne Pro both showed the problem.

...

Below, key facts about the exceedingly ugly digital artifacts which I’ve called “Black Dots in White Spots” (sometimes manifesting as white dots in black spots), which I’ll just call 'pimples' here. They have mangled virtually all of my images from my trip.

I cannot unsee these exceedingly ugly spots on my images. Thousands of them pollute some images, often in the most critical areas. This is the most damnning imaging quality defect I have ever seen in a digital camera in my entire career.

Working theory: Leica is 'cooking' the raw DNG file data with some kind of acutance-enhancing imaging pipeline manipulation of the raw data. The result can be tends of thousands of “pimples” all over the image that are the ugly result of this heavy-handed image processing.

• Subject matter matters. The “pimples” are not seen in areas of uniform tone, but tend to occur in subject matter of higher acutance and fine detail.
• The pimples are made-up FAKE detail. It is just not possible to record (except randomly), a black pixel with a white surround. It would take just the right size dark spot aligned just the right way over the photosites, along with all the surrounding pixels to be brighter. Furthermore, diffraction would quickly exert its effects—yet it does not.
• The pimples “stick” to the subject matter. That is, the spots are not fixed in terms of pixel coordinates*. In other words, this does not appear to be a case of “stuck pixels” or “dead pixels”.
• The pimples are invariant with respect to aperture. Every series I shot (many) all confirm that.
• Might it be an imaging pipeline bug, a camera firmware issue? This idea gets credence from seeing the problem in both the Leica M Monochrom Typ 246 and the Leica M10 Monochrome.

Six years or so ago, I reported on an identical problem with the Leica M Monochrom Typ 246. Two very different sensors, yet the identical issue. This implies software (firmware) mangling of the raw data somewhere in the imaging pipeline. When I reported the issue to Leica years ago (including raw files), the company went radio silent on the issue. As far as I can tell, it looks like the same deeply flawed firmware is still in place. If Leica wants to speak to the issue and its mangling of my images, then I’m all ears.

I’ve added a full aperture series to my page covering this issue:

Leica M10 Monochrom: Black Dots on White Spots Digital Artifacts

Actual pixels crop, 2X linear enlargement showing black dots and white dots pimples

f8 @ 1/250 sec, ISO 160; 2020-12-18 14:00:09
Leica M10 Monochrom + Leica 28mm f/1.4 Summilux-M ASPH + filter B+W 090 Red
ENV: Lundy Canyon, altitude 8100 ft / 2469 m, 28°F / -2°C
RAW: vignetting corrected, push 0.5 stops, +100 Shadows, +15 Clarity, +20 Texture, USM {4,50,0}

[low-res image for bot]

Actual pixels crop, 2X linear enlargement showing black dot in white spot pimples

f5.6 @ 1/1500 sec, ISO 160; 2020-12-21 15:08:25
Leica M10 Monochrom + Zeiss ZM 35mm f/1.4 Distagon + filter B+W 090 Red

[low-res image for bot]

Brian K writes:

Yup, I now see what you are talking about. They weren’t obvious last night when I looked at the files at 100% [diglloyd: 2020 MacBook Pro 16" with Retina Display, see my comment below]. Became very obvious when zooming in beyond that. And then noticeable (though barely) when I looked at the files at 100% again and knew what to look for.

I’m bummed that they are present—was crossing my fingers it was a camera copy issue. It clearly isn’t.

The good news for me is that I can replicate it in a controlled environment in my basement. So I can experiment to see if I can identify any variables that cause it or accentuate/mitigate it. The bricks, strobe, and tripod remain in place.

I took a few pics without a filter but haven’t reviewed them yet. Also took some with a light red filter. Since I didn’t notice the issue in the worst case scenario, I didn’t bother reviewing those pics. I now need to.

Depending on what those images show, I may shoot a filter series to see if there is a light cutoff value that relates to the artifacts

I also plan to shoot an ISO series to see if there is an ISO value that influences the presence of these artifacts. I recall that the MM had a relatively high base ISO and one of the features of the M10M was that base ISO was lower. I wonder if this could be a compromise Leica accepted in an effort to get the base ISO lower.

I also want to shoot the scene with the SL2 and the same lens. I do not expect to see the pimples, but won’t know until I actually shoot it. May also shoot it with my D850, Z7, and A7RIII. My suspicion is that it won’t show up on these color sensors, but I don’t look at images at greater than 100% and I need to prove to myself that this isn’t a problem in general with this type of scene and is specific to the M10M. Since I now have a controlled setup, seems silly not to be thorough.

Thanks for your replies. Good stuff.

DIGLLOYD: viewing at 100% on a Retina display of about 220 ppi makes the pimples hard to see (at the threshold of the resolving power of the eye—use a display of 110 ppi or so.

I’d bet that there exist no Leica M10M camera bodies that are free of the issue, since my top hypothesis is that it is a firmware signal processing / acutance enhancement behavior, or something of that nature.

If am so sure of myself that I’ll bet a 2-year subscription ($400 value) against any Leica M10M camera body. Anyone who wishes to take me up on the offer can send me their M10M—to become mine when I prove the pimples are there. I don’t expect any takers, but even with its defects, I’ll happily acquire an M10M this way.

Also, I can align a Leica M10-R image shot in an A/B comparison and get a perfect overlay of black spot pimples in the same place for subject matter. The demosaicing blurs things a little and makes it less obvious, but for the same subject matter, the pimples are in exactly the same place.

I do not expect to see the pimples on the Leica SL2 since it is a totally different sensor (without micro lenses AFAIK as well as different resolution and sensor tech), and the firmware might vary accordingly.

Leica M10 Monochrom Examples: Alabama Hills, Lone Pine Lake, Mt Whitney Trail

The page looks at performance of the Leica M10 Monochrom with various lenses.

Leica M10 Monochrom Examples: Alabama Hills, Lone Pine Lake, Mt Whitney Trail

Includes images at up to full resolution, plus crops.

CLICK TO VIEW: Leica M10-R/M10m system

Thick Clear Ice on Lone Pine Lake

f8 @ 1/180 sec, ISO 160; 2020-12-23 13:53:34
Leica M10 Monochrom + Leica 24mm f/3.8 Elmar-M ASPH + filter B+W 091 Deep Red
ENV: Lone Pine Lake, altitude 10040 ft / 3060 m, 18°F / -7°C
RAW: push 0.55 stops, +100 Shadows, -81 Highlights, +41 Whites, +50 Dehaze, +15 Clarity, USM {8,50,0}

[low-res image for bot]

Zeiss ZM 35mm f/1.4 Distagon Aperture Series: View Over Alabama Hills to Lone Pine Peak and Mt Whitney (Leica M1-R)

This series from f/1.4 through f/8 examines total imaging performance of the Zeiss ZM 35mm f/1.4 Distagon on a distance scene, which reveals lens faults mercilessly. Sharpness near-to-far and across-the-field along with field curvature, focus shift and general imaging performance.

Also, a useful discussion of just important the focus position with the frame can be to total sharpness.

Zeiss ZM 35mm f/1.4 Distagon Aperture Series: View Over Alabama Hills to Lone Pine Peak and Mt Whitney

Includes images from f/1.4 through f/8 at up to full resolution, plus crops.

CLICK TO VIEW: Leica M10-R/M10m system

View Over Alabama Hills to Lone Pine Peak and Mt Whitney

f5.6 @ 1/90 sec, ISO 100; 2020-12-25 12:59:14
LEICA M10-R + Zeiss ZM 35mm f/1.4 Distagon
ENV: Alabama Hills, altitude 4200 ft / 1280 m, 58°F / 14°C
RAW: +22 Whites, +15 Dehaze, +15 Clarity, USM {10,50,0}

[low-res image for bot]

Sensor Bifurcation, Stitched Sensors: More Insight From Readers

See my detailed post on the Leica M10 Monochrom sensor bifurcation defect, which damaged all of my Eureka Dunes images.

Sensor bifurcation with Leica SL2

Dan Llewelyn of MaxMax.com writes:

After talking to a few sources that really know what they are talking about, all FF sensors are stitched - at least with current technology.  And one of these sources sells a lot of ITAR stuff so, while maybe there some super secret military foundry out there, APS is the current limit.

The stitch line is always visible if you don’t process it out; could be very subtle, but it’s there. For very large pixels it might not be visible, but that’s probably sensors with >10-20um pixels. 

Modern steppers are ~30x30 these days. To step a 35mm device in 2 shots you need ~28-30 in one direction (24mm active area + dark pixels + periphery column circuits + bond pads =~28 minimum).

So, I think my initial guess is correct.  The line you are seeing on the Leica M10M is the stitching line and more apparent because of the lack of CFA, AA and the debayering which would smooth things out.  But Leica needs to do a better job in processing that stitch.  And part of the problem might be is that they are using an older, less expensive foundry that doesn't stitch as well (pretty likely IMO).

BTW, on a sensor like the Nikon D800, Nikon D810 and Nikon D850 - there is *no* visible stitch line - at least I can't see it when I look at the sensor. 

My guess is that the camera manufacturers really don't want that fact out-of-the-bag.  Otherwise, next thing you know, you will have pixel peepers taking pictures of white skies are processing the hell out of the image to find the line and then sending the camera in for repair because of a 'defective' sensor when in real life, they would have never noticed it. 

DIGLLOYD: I never saw any sensor bifurcation on the Nikon D850 Monochrome, which is a color camera with its color filter array removed by Dan at MaxMax.com. If Dan says there is no visible stitch line, I believe him—he has spent a ton of time with some advanced equipment doing these conversions.

Put another way, it might be fairly said that Leica is shipping inferior sensors compared to Nikon. Presumably they could source (at greater cost) better quality sensors. I’d be very curious to test the PhaseOne Achromatic to see if any sensor bifurcation is seen.

Roy P writes:

I finally have a definitive answer.  These larger sensors are optically stitched together, using multiple reticle exposures on a single wafer.  It looks like the fab that makes the Leica sensors for the SL2 and M cameras is using two exposures.  Sony maybe processing its 35mm sensors in one shot.  But almost certainly, doing optical stitching for the medium formats.

My friend says overlay is a non-issue with a 3.x micron pitch, and that is very true.  However, I couldn’t see how that would work for the peripheral logic (DRAMs, sense amplifiers, line drivers, registers where the data is latched, etc.)  The obvious answer is, they must be making this part of the chip also using big geometries, i.e., not 14 nm or 10 nm, maybe more like 130 or even 250 nm, perhaps.

DIGLLOYD: there is surely some quality variation at different fabs. Leica is probably trying to keep costs low, and also might be accepting sensors of lower grade—how else to explain an obvious flaw that has damaged all my images? For that matter, I wonder if the white-dot pimples are some other kind of sensor flaw, and also unfixable. Leica went radio-silent wen I reported the bug with the Leica M Monochrom Typ 246—there’s some dirty little secret that is not discussable, it seems.

Roy P continues:

...what is interesting is, in theory, they should be able to use this exact same process to make 8” x 8” sensors on a 300 mm wafer.  That is the largest square you can fit into a circle with a 300 mm diameter, which therefore also means that’s the minimum image circle you would need the lenses to generate for a camera with such a big sensor.  So even if wide angle lenses are impractical, normal (say, 50 mm equivalent) lenses.

The Voigtlander 50 APO for Sony has a front element that looks about 1” diameter.  So for a camera with an 8” x 8” sensor, it should be possible to build a 50 mm equivalent lens with a front element of perhaps around 8” diameter.  Assuming the lens-making cost scales geometrically, such a lens should cost about 64x what the CV50 APO costs, meaning about $68,000.  Which is not really too bad!

Unfortunately, the sensor would probably cost $300,000, assuming the sensor in the Phase One IQ4 150MP backs cost about $15K (200 mm x 200 mm vs. 54 mm x 40 mm).  So it should be possible to build a ~$400,000 camera with an 8” x 8” sensor, with a resolution of about 1.2 gigapixels, with a Voigtlander 50 APO Lanthar quality lens!

DIGLLOYD: a 50mm lens on a sensor that size would be a 8mm field of view equivalent. I don't think such a lens is feasible, and the ray angle issues would be godawful. I’d want something more like 135mm, which would be about a 25mm field of view equivalent. It would need to be f/8 or so to be practical.

Leaf 80-megapixel digital back circa 2010
image courtesy of MaxMax.com

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Leica 24mm f/3.8 Elmar-M ASPH Aperture Series: Sunstar Over as yet Unfrozen Beaver Pond (Leica M1-R)

This aperture series from f/4 through f/16 takes a critical look at near-to-far and across-the-frame sharpness as well as field curvature for the Leica 24mm f/3.8 Elmar-M ASPH on the 40MP Leica M10 Monochrom.

Leica 24mm f/3.8 Elmar-M ASPH Aperture Series: Sunstar Over as yet Unfrozen Beaver Pond

Includes images from f/4 through f/16 at up to full resolution, plus crops.

CLICK TO VIEW: Leica M10-R/M10m system

Sunstar Over as yet Unfrozen Beaver Pond

f8 @ 1/250 sec, ISO 160; 2020-12-19 14:54:49
Leica M10 Monochrom + Leica 24mm f/3.8 Elmar-M ASPH
ENV: Lundy Canyon, altitude 8000 ft / 2438 m, 28°F / -2°C
RAW: push 0.8 stops, +100 Shadows, -100 Highlights, +50 Whites, +50 Dehaze

[low-res image for bot]

Leica 28mm f/1.4 Summilux-M ASPH Aperture Series: View Over Alabama Hills to Lone Pine Peak and Mt Whitney (Leica M1-R)

This series from f/1.4 through f/11 examines total imaging performance of the Leica 28mm f/1.4 Summilux-M ASPH on a distance scene, which is unforgiving of lens fault. Sharpness near-to-far and across-the-field along with field curvature, focus shift and general imaging performance. Also, a surprisingly strong amount of violet fringing.

Leica 28mm f/1.4 Summilux-M ASPH Aperture Series: View Over Alabama Hills to Lone Pine Peak and Mt Whitney

Includes images from f/1.4 through f/11 at up to full resolution, plus crops.

Call me unimpressed. Sony mirrorless has nothing to apologize for.

CLICK TO VIEW: Leica M10-R/M10m system

View Over Alabama Hills to Lone Pine Peak and Mt Whitney

f8 @ 1/90 sec, ISO 100; 2020-12-25 12:51:02
LEICA M10-R + Leica 28mm f/1.4 Summilux-M ASPH
ENV: Alabama Hills, altitude 4200 ft / 1280 m, 55°F / 12°C
RAW: +50 Shadows, +22 Whites, +15 Dehaze, +15 Clarity, USM {10,50,0}

[low-res image for bot]

Leica 28mm f/1.4 Summilux-M ASPH Aperture Series: Backlit Snowy Meadow, Lundy Canyon (Leica M10 Monochrom)

This series from f/1.4 through f/16 examines total imaging performance of the Leica 28mm f/1.4 Summilux-M ASPH. Sharpness near-to-far and across-the-field along with field curvature, focus shift and general imaging performance. As well, how well f/16 holds up (not so well) versus f/11.

Leica 28mm f/1.4 Summilux-M ASPH Aperture Series: Backlit Snowy Meadow, Lundy Canyon

Includes images from f/1.4 through f/16 at up to full resolution, plus crops.

CLICK TO VIEW: Leica M10-R/M10m system and top-grade lenses

Backlit Snowy Meadow, Lundy Canyon

f8 @ 1/500 sec, ISO 160; 2020-12-19 13:11:41
Leica M10 Monochrom + Leica 28mm f/1.4 Summilux-M ASPH
ENV: Lundy Canyon, altitude 8000 ft / 2438 m, 28°F / -2°C
RAW: push 0.1 stops, +100 Shadows, -50 Highlights, +30 Whites, +50 Dehaze, +15 Clarity

[low-res image for bot]

Zeiss ZM 35mm f/1.4 Distagon Aperture Series: Animal Tracks near Snowy Creek, Lundy Canyon (Leica M10-R)

This series from f/1.4 through f/16 examines imaging performance of the Zeiss ZM 35mm f/1.4 Distagon focused at medium distance distance through an intermediate zone with strong demands on near to far depth of field.

Zeiss ZM 35mm f/1.4 Distagon Aperture Series: Animal Tracks near Snowy Creek, Lundy Canyon

Includes images from f/1.4 through f/11 at up to full resolution, as well as a 3-frame focus stack at f/9, plus crops.

CLICK TO VIEW: Leica M10-R/M10m system and top-grade lenses

Animal Tracks near Snowy Creek, Lundy Canyon

f9 @ 1/45 sec focus stack 3 frames, ISO 100; 2020-12-17 23:10:42
LEICA M10-R + Zeiss ZM 35mm f/1.4 Distagon
ENV: Lundy Canyon, altitude 8000 ft / 2438 m, 18°F / -7°C
RAW: USM {6,50,0}

[low-res image for bot]

Zeiss ZM 35mm f/1.4 Distagon Aperture Series: Frosty Creek to Snowy Mountainside, Lundy Canyon (Leica M10-R)

This series from f/1.4 through f/16 examines imaging performance of the Zeiss ZM 35mm f/1.4 Distagon focused at far distance through an intermediate zone. Aperture f/11 is subject to moderate diffraction dulling for fine detail, and f/16 much more so. However, while f/16 is impacted in a major way on a 60MP sensor, with the 40MP sensor of the Leica M10-R, diffraction effects at f/16 remain tolerable when diffraction mitigating sharpening is used.

Zeiss ZM 35mm f/1.4 Distagon Aperture Series: Frosty Creek to Snowy Mountainside, Lundy Canyon

Includes images up to full camera resolution from f/1.4 to f/16, plus crops.

The about $2290 Zeiss ZM 35mm f/1.4 Distagon is not only the best performing lens for the Leica M10 Monochrom and Leica M10-R, at 1/4 to 1/6 the price of Leica-brand lenses it’s a ridiculously cheap 'steal' by comparison. If you were to buy only one lens for Leica M, the ZM 35/1.4 offers the best performance, best value, and is a great all-around focal length.

CLICK TO VIEW: Leica M10-R/M10m system and top-grade lenses

Frosty Creek to Snowy Mountainside

f5.6 @ 1/90 sec, ISO 100; 2020-12-17 23:32:34
LEICA M10-R + Zeiss ZM 35mm f/1.4 Distagon
ENV: Lundy Canyon, altitude 8000 ft / 2438 m, 18°F / -7°C
RAW: vignetting corrected

[low-res image for bot]

Leica 18mm f/3.8 Super-Elmar-M ASPH Aperture Series: Setting Sunstar Over Snowy Beaver Pond (Leica M10-R)

This aperture series from f/4 through f/11 looks at near-to-far and across-the-frame sharpness for the Leica 18mm f/3.8 Super-Elmar-M ASPH on the 40MP Leica M10-R.

Leica 18mm f/3.8 Super-Elmar-M ASPH Aperture Series: Setting Sunstar Over Snowy Beaver Pond

Includes images up to full camera resolution from f/4 to f/11, plus crops.

Regrettably, Leica has quietly discontinued the Leica 18mm f/3.8 Super-Elmar-M ASPH as well as the Leica 24mm f/3.8 Elmar-M ASPH, two of my favorites for landscape shooting. As well as the Leica 24mm f/1.4 Summilux-M ASPH. What is the future of a platform where some of its most appealing lenses go out of production?

CLICK TO VIEW: Leica M10-R/M10m system and top-grade lenses

Setting Sunstar Over Snowy Beaver Pond

f8 @ 1/350 sec, ISO 100; 2020-12-18 02:46:53
LEICA M10-R + Leica 18mm f/3.8 Super-Elmar-M ASPH
ENV: Lundy Canyon, altitude 8000 ft / 2438 m, 28°F / -2°C
RAW: LACA corrected, vignetting corrected, push 0.1 stops, +40 Shadows, -76 Highlights, +45 Whites, USM {8,50,0}

[low-res image for bot]

OWC Elektron USB-C SSD Trounces the Samsung T7

re: Samsung T5
re: OWC Elektron

CLICK TO VIEW: High Performance SSDs

Samsung T7 is about $270 @AMAZON. Is $100 for 2nd-rate performance worth it?

The price difference is modest, but the performance difference is huge. Below, Samsung T7 performance (red/green) is a fraction of the about $379 OWC Elektron (orange/blue, top lines way above the Samsung lines).

For anyone who really wants the best, the OWC Elektron trounces the Samsung T7 whenever sustained I/O performance is a goal, as the graph shows. And the OWC Elektron is also IP67 water resistance and virtually indestructible vs the Samsung.

Samsung T7 vs OWC Elektron, sustained transfer speed across capacity

Sensor Bifurcation, Stitched Sensors: Affects Leica M10 Monochrom, Leica M10-R, Leica SL2, some Medium Format

Update Jan 11: see Sensor Bifurcation, Stitched Sensors: More Insight From Readers.

See my detailed post on the Leica M10 Monochrom sensor bifurcation defect, which damaged all of my Eureka Dunes images.

Ding writes:

Sensor bifurcation with Leica SL2

Though I’m no longer a paid subscriber to your website, I still check your valuable articles from time to time.

After reading your article on sensor bifurcation, I have checked a lot of images taken with my Leica M10-R. Yes, the issue does exist. In fact, if you push dehaze and clarity to maximum in Lightroom, these’s a good chance than you’ll see the vertical line, especially in a landscape shot with sky across the image horizontally.
Though in real life I will never push this far in LR, and the bifurcation won’t happen every time, it is still very disappointing to have a flawed sensor which Leica might use for at least 4-5 years to come.

I have also checked some images from Leica SL2, and have noticed a similar bifurcation issue, with texture, clarity and dehaze maxed out in LR. Since I don’t have a Panasonic S1R, I am not able verify if this issue exists on S1R as well. You may download the DNG file from the dropbox link below. The image was taken with SL2 and Apo-Summicron-SL 35.

...

DIGLLOYD: I’ve examined the raw file — no need for Clarity at all, and Dehaze of around 50 makes the sensor bifurcation visible. As shown, Dehaze was set to 100 to make it obvious. The Dehaze setting is a form of sharpening, and what it does is accentuate the left/right luminance variance splitting the image into left and right halves, hence a dividing line.

A color camera masks the issue much more, due to demosaicing and a bit more noise. A monochrome sensor has lower noise and no demosaicing, so flaws stand out.

Such adjustments to the M10-R image are way beyond what I would use for a color sensor, but as a point of fact, it’s clear that the Leica SL2 sensor and Leica M10-R sensors both have the same sensor bifurcation issue as the Leica M10 Monochrom. It’s just not likely to become visible on a color sensor.

While it seems likely that it’s a non-issue for the color cameras, the fact is that the sensor bifurcation of the Leica M10 Monochrom damaged a large number of my images. Therefore, I deem it an unacceptable defect, and that’s in addition to the ugly white-dot pimple problem. That said, many Leica M10m users won’t care because it’s either not put to use as a landscape camera and/or it will be used at higher ISOs, where noise will overwhelm (dither away) the left/right brightness difference of the two halves of the sensor.

Dan Llewelyn of MaxMax.com writes:

With a color camera and the debayering used, and if there is an OLPF filter, and maybe even some firmware tricks, you can get away with it.  But when you have a monochrome sensor with no OLPF, you are going to see the problem *much* easier.  I think the reason some of my customers saw the problem after I modified their  D700's to IR, is that the OLPF was removed and above 800nm, the sensor is basically monochrome.

One of the things I wonder is how many different cameras have stitched sensors?  

I pinged a friend I have known who has been in the industry a long, long time and worked for many camera companies.  At one point, we was one of the guys designing the Kodak medium format sensors.

He says, most (read that all that he knows of) consumer FF sensors are stitched because of limits of the stepper reticles FOV.  He basically said that with a stitched sensor, each sensor needs to be individually calibrated to deal with stitch anomalies and part of that calibration is wavelength dependent which is why a NIR camera will show the stitch more.  He went into a lot of technical details that I can't disclose but basically there is a bunch of calibrations done on each individual sensor so if you have a camera that shows the stitching line, and it is bad enough, then the only real option is to send it back to the factory to see if they can calibrate it better.  But, I suspect, those calibrations are done at the actual factory and not the USA service center.  

DIGLLOYD: Leica takes months to do basic service, in my personal experience and that of Roy P.

I have/had not noticed the sensor bifurcation issue with any camera/sensor but Leica.

Many sensors were (all still are?) manufactured as 'tiles', such as shown below with the circa-2010 Leaf 80MP digital back, consisting of eight (8) tiles. The same obvious tiling effect of stitched sensor can be seen in the picture at Photigy.com of the Leaf Aptus-II 54 X 40mm digital back.

Leaf 80-megapixel digital back circa 2010
image courtesy of MaxMax.com

Leica 50mm f/2 APO-Summicron-M ASPH Aperture Series: Lone Pine Peak and Mt Whitney Sunrise from Alabama Hills (Leica M10-R)

This aperture series from f/2 through f/8 examines sharpness across the field and near to far, taking a critical look at field curvature, which is pronounced enough to cause dramatic differences in sharpness across the field, a headache for this type of photography.

I had been having some trouble figuring out the disappointing results with the 50/2 APO in a variety of situations—it performed poorly in the outer zones when focused near the center on everything. It was a puzzler, but this series is a revelation as to what is going on.

Leica 50mm f/2 APO-Summicron-M ASPH Aperture Series: Lone Pine Peak and Mt Whitney Sunrise from Alabama Hills

Includes images up to full camera resolution from f/2 to f/8, plus crops.

This series is entirely consistent with the examples readers have sent me over the years, which also show disappointing across-the-field sharpness. If you want the best, dispense with the marketing hype and false premises, and look at reality.

You can get far superior performance 3 stops earlier with 50% more pixels for 1/8 the price. And soon, in Leica M mount.

CLICK TO VIEW: King of the Mountain 50mm Performance vs Marketing BS

Lone Pine Peak and Mt Whitney Sunrise from Alabama Hills

f5.6 @ 1/12 sec, ISO 100; 2020-12-26 07:09:11
LEICA M10-R + Leica 50mm f/2 APO-Summicron-M ASPH
ENV: Alabama Hills, altitude 6000 ft / 1829 m, 42°F / 5°C
RAW: pull 0.45 stops, +35 Whites, +10 Dehaze, +15 Clarity

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Leica 24mm f/3.8 Elmar-M ASPH Aperture Series: Lone Pine Peak and Mt Whitney Sunrise from Alabama Hills (Leica M10-R)

This aperture series from f/3.8 through f/11 takes a critical look at near-to-far and across-the-frame sharpness for the Leica 24mm f/3.8 Elmar-M ASPH on the 40MP Leica M10-R, in particular field curvature and depth of field, and gives a tip on how to optimize focus placement for scenes like this, which is critical to obtaining peak sharpness.

Leica 24mm f/3.8 Elmar-M ASPH Aperture Series: Lone Pine Peak and Mt Whitney Sunrise from Alabama Hills

Includes images up to full camera resolution from f/3.8 to f/11, plus crops.

CLICK TO VIEW: Leica M10-R/M10m system and top-grade lenses

Lone Pine Peak and Mt Whitney Sunrise from Alabama Hills

f8 @ 1/12 sec, ISO 100; 2020-12-26 07:06:02
LEICA M10-R + Leica 24mm f/3.8 Elmar-M ASPH
ENV: Alabama Hills, altitude 6200 ft / 1890 m, 42°F / 5°C
RAW: vignetting corrected, pull 0.45 stops, +35 Whites, +10 Dehaze, +15 Clarity

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FOR SALE: View Camera Lenses: Rodenstock 135m f/5.6 APO-Sironar-S, Schneider 400mm f/5.6 APO-Tele-Xenar Compact

All items with original box, lenses with lens caps, etc. Clear and clean glass, known-good lens samples owned by Lloyd

• Rodenstock 135mm f/5.6 APO-Sironar-S Copal shutter + Linhof Technikardan lens board $1250 PRISTINE
• Schneider 400mm f/5.6 APO-TELE-XENAR Copal shutter+ Linhof Technikardan lens board $1750 PRISTINE
• Schneider 150mm f/4 Tele-Xenar medium format lens.
• Carl Zeiss Jena 180mm f/2.8 MC Sonnar medium format lens

Local sale (San Francisco Bay Area) preferred so buyer can inspect lens, but other options possible. Contact Lloyd.

FOR SALE: Leica M Type 240, Leica 21mm f/3.4 Elmar-M ASPH, Leica 28mm f/2 Summicron-M ASPH Leica 100mm f/2.8 Elmarit-R ASPH

All items with original box, lenses with lens caps, etc. Clear and clean glass, known-good lens samples owned by Lloyd

• $2750 Leica M Typ 240 (black) with 4 batteries and 2 chargers, original box, Really Right Stuff L-bracket, EVF
• $2550 Leica 21mm f/3.4 Elmar-M ASPH
• $2650 Leica 28mm f/2 Summicron-M ASPH
• $1850 Leica 100mm f/2.8 Elmarit-R ASPH

Local sale (San Francisco Bay Area) preferred so buyer can inspect lens, but other options possible. Contact Lloyd.

FOR SALE: Canon EF 200mm f/1.8L USM

I'm selling this lens on behalf of a friend.

As some readers might know the Canon EF 200mm f/1.8L is a beautiful supertele long lusted over that has become a collector’s item—not many were made.

• Glass looks perfect front and rear and through, lens is not mint but looks close to it.
• Field shots show perfect performance on the 50 megapixel Canon 5DS R—sharp as a tack across the field.
• Includes Canon lens hood and hardcase and warranty card (out of warranty, USA).
• I am including the Canon EF 1.4X II tele extender
• Circular drop-in filter holder and spare one.
• Includes original lens foot plus Really Right Stuff LCF-40 Foot.
• USA warranty card

Local sale (San Francisco Bay Area) preferred so buyer can inspect lens, other areas possible with travel (Eastern Sierra, Reno, NV, a few others). Contact Lloyd. $5500 or best offer.

Canon EF 200mm f/1.8L and stuff

f1.8 @ 1/100 sec, ISO 20; 2019-09-15 09:22:47
iPhone 7 Plus + iPhone 7 Plus 4.0 mm f/1.8 ENV: altitude 473 ft / 144 m

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Canon EF 200mm f/1.8L, side view with controls

f1.8 @ 1/120 sec, ISO 20; 2019-09-15 09:26:22
iPhone 7 Plus + iPhone 7 Plus 4.0 mm f/1.8 ENV: altitude 492 ft / 150 m

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Canon EF 200mm f/1.8L, side view with Really Right Stuff lens foot

f1.8 @ 1/120 sec, ISO 25; 2019-09-15 09:26:55
iPhone 7 Plus + iPhone 7 Plus 4.0 mm f/1.8 ENV: altitude 491 ft / 150 m

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Canon EF 200mm f/1.8L, front glass

f1.8 @ 1/60 sec, ISO 25; 2019-09-15 09:27:19
iPhone 7 Plus + iPhone 7 Plus 4.0 mm f/1.8 ENV: altitude 493 ft / 150 m

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Canon EF 200mm f/1.8L, ZZZZ

f1.8 @ 1/120 sec, ISO 40; 2019-09-15 09:27:35
iPhone 7 Plus + iPhone 7 Plus 4.0 mm f/1.8 ENV: altitude 491 ft / 150 m

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Leica 24mm f/3.8 Elmar-M ASPH Aperture Series: Ancient Tree Trunk at Lone Pine Lake (Leica M10 Monochrom)

This aperture series from f/3.8 through f/11 takes a critical look at near-to-far and across-the-frame sharpness for the Leica 24mm f/3.8 Elmar-M ASPH on the 40MP Leica M10 Monochrom, discussing focus shift and field curvature and depth of field, and gives a tip on how to optimize focus placement for scenes like this.

Leica 24mm f/3.8 Elmar-M ASPH Aperture Series: Ancient Tree Trunk at Lone Pine Lake

Includes images up to full camera resolution from f/3.8 to f/11, plus crops.

CLICK TO VIEW: Leica M10-R/M10m system and top-grade lenses

Ancient Tree Trunk at Lone Pine Lake

f8 @ 1/60 sec mechanical shutter, ISO 160; 2020-12-23 13:23:07
LEICA M10 MONOCHROM + Leica Elmar-M 3.8/24 ASPH + filter B+W 091 Dark Red
ENV: Lone Pine Lake, altitude 9920 ft / 3024 m, 18°F / -7°C
RAW: vignetting corrected, USM {10,50,0}
bitterly cold

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Leica M10 Monochrome: Long Exposures at Night

I look at exposure times of 6 minutes and 16 minutes on the Leica M10 Monochrom using long exposure noise reduction in freezing temperatures.

Leica M10 Monochrome Long Exposures at ISO 160

Should make prospective M10m users pleased!

CLICK TO VIEW: Leica M10-R/M10m system and top-grade lenses

f4 @ 360.0 sec, ISO 160; 2020-12-24 19:30:39
Leica M10 Monochrom + Zeiss ZM 35mm f/1.4 Distagon
ENV: Alabama Hills, altitude 4200 ft / 1280 m, 32°F / 0°C
RAW: vignetting corrected, +30 Whites, +30 Dehaze, +15 Clarity

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Leica M10 Monochrome: an Essay on Its Noise Characteristics vs Alternatives

By most standards, the Leica M10 Monochrom is low-noise.

Or is that just dropping context?

Leica M10 Monochrome Noise Discussion

Sometimes, cognitive commitments an confirmation bias just leave stuff out.