Very Strong Banding Problem

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I have come up with a very strong pseudo-linear banding problem. It rearly occurs. I had it horizontally in a landscape photo last weeken near to the direct sunlight with iso 160 and zeiss 28 mm. But this time it appears with artificial lighting at is0 1250 with summarit 50. First link is the photo with banding (upleft corner) and the second one absolutely without it. Has anyone find out this type of imaging error and what should I do?

http://gallery.photo.net/photo/7651317-lg.jpg

http://gallery.photo.net/photo/7651326-lg.jpg
 
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I wonder if this is that "green blob" issue that was supposed to be fixed on many cameras.. .

Dave
 
Yep that's it alright. I used to get them all the time and, as far as I know, Leica have stated there is no fix for it.
 
dcsang said:
I wonder if this is that "green blob" issue that was supposed to be fixed on many cameras.. .

Dave
Click to expand...

No, that was really blobs, not banding. This is an issue caused by light from an edge-of-frame highlight striking the reference pixels at the edge. Some cameras do it, most don't There is no remedy.
 
I've occasionally had this. It's caused by light from a very bright source that's just outside the frame finding it's way onto shielded black level reference pixels at the edge of the sensor. Since there are more green pixels than others it appears as a black to dark green horizontal band. The band only extends half way across the frame because the two haves of the sensor array are read out by separate circuits. AFAIK it's a characteristic of the sensor (internal light piping between dielectric layers) and is not easily fixed.

The horizontal streaking experienced by early cameras when photographing, for example, dark interiors with bright windows/frames was fixed during the recall. AFAIK the fix involved adding a low impedance ground strap to one of the analog circuit boards to minimise crosstalk/noise.

Bob.
 
Thank you all. I am a little bit confused about about sending back the body for guarantee. but I guess there is no solution for this problem and I have to live with it like many other M8 users.
 
Today this problem hit me for the first time. This is strange because I already had similar pictures with the sun in front of me and those pictures do not show that behavior.
 

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tom.w.bn said:
Today this problem hit me for the first time. This is strange because I already had similar pictures with the sun in front of me and those pictures do not show that behavior.
Click to expand...

Your picture shows the problem of light from a bright source at the very outside edge of the frame reaching the dark reference pixels. The band stops half way across the image. For the problem to appear you will find the position of the edge light source is very very critical, that's why it occurs so infrequently in practice. If you do a careful experiment I believe all M8s can be made to show this effect. So far I've tried this with 4 cameras and all could be made to show the streak.

Bob.
 
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