EXCERPT page containing first few paragraphs. 2024-04-18 00:57:40
UA_SEARCH_BOT_null @ 18.118.200.86
For full access, subscribe here. Or click title to login. 
Sensor Defect: Bad Pixel Column (M9 CCD)
Leica apparently considers bad pixel column(s) to be of acceptable quality: see also Bad CMOS Sensor: Entire Column Mapped Out (M Monochrom Typ 246).
Observe the zipper-like vertical line running through the orange roof tiles.
The zipper-like vertical line is a sensor defect.
My theory (which I am not certain of) is that sensor defects like this cannot be hidden on a camera like the Leica M9 which lacks an anti-aliasing filters, which perhaps is one reason that manufacturers insist on using an AA filter.
At every aperture from f/1.4 through f/11, this sensor defect is readily apparent. Stopping down to f/16, the problem all but disappears, revealing only a few artifacts, leading me to one possible theory: diffraction acts as an anti-aliasing filter, blurring at the pixel level enough to eliminate the error. That is my theory, and it might not be correct, since I don’t know the exact nature of the issue. (Note that stopping down is also one way to eliminate other digital artifacts such as moiré).
Article continues for subscribers...
Diglloyd Guide to Leica is by yearly subscription. Subscribe now for about 25 cents a day ($90/year).
BEST DEAL: get full access to ALL 8 PUBLICATIONS for about 75 cents a day!
Diglloyd Guide to LEICA contains in-depth coverage of Leica M system cameras and lenses, with additional coverage of Leica M Monochrom, Leica Q.
Special emphasis is placed on Leica M lenses and certain Zeiss ZM lenses.
- Make better images by learning how to get the best results right away.
- Save money by choosing the right lens for your needs the first time, particularly the Summilux/Summicron/Elmarit choice and/or Zeiss ZM.
- Make better images, a sort of “cheat sheet” saving yourself months or years of ad-hoc learning. Processing parameters are discussed and shown.
- Jaw-dropping image quality found nowhere else utilizing Retina-grade images up to full camera resolution, plus large crops [past 2 years or so].
- Real world examples with insights found nowhere else. Make sharper images just by understanding lens behavior you won’t read about elsewhere.
- Aperture series from wide open through stopped down, showing the full range of lens performance and bokeh.
- Optical quality analysis of field curvature, focus shift, sharpness, flare, distortion, and performance in the field.
Want a preview? Click on any page below to see an excerpt as well as extensive blog coverage, for example on Leica.
