Get Leica M Monochrom Typ 246 at B&H Photo.
Update 6 July 2015: I received a note from Leica saying that the issue is reproducible on their end and that the behavior is being researched.
I’m not sure what to make of this bizarre artifact, which is seen even with sharpening set to zero in Adobe Camera Raw. Is it a sensor defect, a camera defect, a raw converter issue? I don’t know, but I would not be a buyer of the Leica M Typ 246 until the answer becomes clear. I hope to see the issue appear reproduced using another raw converter besides ACR (thus ruling out the raw converter), but so far Iridient Developer won’t open the DNGc files even though it ostensibly supports the MM246.
UPDATE: I have confirmed with Brian Griffith of Iridient Digital that the spots are seen when converting with Iridient Developer. So unfortunately the black spots are “baked in” to the raw file.
Two entirely different examples are shown which are consistent in the behavior, both at ISO 320, so this is not a noise issue (besides, it is not random at all, but 100% predictable as a black dot inside a small white spot). Use of a 10X magnifying loupe on the actual fabric shown below proves that these dark spots do not exist in reality. Other images suggest a reverse “white spot in black dot” issue as well, but I need to confirm that with more than one image.
It looks to me like a camera/sensor defect and I strongly suspect the damage is baked into the raw files I shot. But I retain a small hope that it’s the ACR engine, not the raw file itself.
This image, gorgeous in its tones, but has tiny little pimples all over the image (plain to see in the full-size image).