M9 Horizontal lines / striation

[adan]

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Regarding the green lines that cover half the image.

 

They affect only half the image because the sensor data is read out via two channels from the center of the pixel rows (like an audience leaving a row of seats into two aisles in a theater) to save time.

 

The green lines specificially are usually caused by inadvertant exposure of "reference pixels" at the end of the pixel rows, which are supposedly hidden from light behind a mask to measure "black." If light leaks under the mask - usually due to an extremely bright part of the subject falling exactly on the edge of the picture - the reference value for black gets "fogged" and produces a green band with width of the offending highlight.

 

A very common effect on M8/8.2s - mostly fixed on M9/M9-P/MM etc. If there is absolutely no chance that there was something bright just outside the frame (and that appears to be the case of the body-builder image) - then it is some other kind of image-processing problem in the camera circuits (not necessarily the sensor chip itself), and does require a trip to Leica.

 

The white bar over the boy's face looks more like an SD card problem - the card lost track of which data goes to which part of the image, and substituted some white sky in that area. Sometimes even substitutes a part of a different image.