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07-14-2019, 11:01 AM   #16
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QuoteOriginally posted by stevebrot Quote
I am wondering if a light leak...
The OP wrote that the dark frames were taken in a dark room. Light leak seems unlikely.

07-14-2019, 11:14 AM   #17
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QuoteOriginally posted by DeadJohn Quote
The OP wrote that the dark frames were taken in a dark room. Light leak seems unlikely.
Good point, though it is good to consider all possibilities. The notion of highly-localized "amp glow" is increasingly attractive. I know of a few KP owners local to me and may ask that one of them stop by for a round of testing to try to reproduce this problem both with and without putting the camera "on ice".


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07-14-2019, 01:38 PM   #18
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QuoteOriginally posted by DeadJohn Quote
The OP wrote that the dark frames were taken in a dark room. Light leak seems unlikely.
Looking through my KP photos, here are two that seem to meet the requirements - high ISO, dark area, and a tad underexposed. I don't see a consistent edge, or any other, effect. These are JPEGs produced by the camera.

The software here doesn't read ISO values over 65535 correctly.
The first one has ISO=102400.
The second one has ISO=819200.
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07-14-2019, 05:23 PM   #19
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QuoteOriginally posted by reh321 Quote
Looking through my KP photos, here are two that seem to meet the requirements - high ISO, dark area, and a tad underexposed. I don't see a consistent edge, or any other, effect. These are JPEGs produced by the camera.

The software here doesn't read ISO values over 65535 correctly.
The first one has ISO=102400.
The second one has ISO=819200.
After several tests, the range of ISO affected seems to be from 800 to 6400. The visibility of the magenta area depends on the colour and lightness of the subject. I took many shots at 8000 and 12800 ISO where I can't see any banding at all, while on some 3200 and 6400 ISO shots it is visible on the jpegs too.
And no, I deliberately took the shots in total darkness. When you test something you must reduce the number of variables at minimum.

07-26-2019, 07:38 AM - 1 Like   #20
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Update: I've contacted directly Ricoh Pentax and they answered quickly enough. I've been contacted by mr. Tohru Kodama, After Sales manager for Ricoh Europe.
After a series of emails trying to let them check directly one of their KP bodies, he admitted that at least in Asia there have been a few cases (but at first he said it was the first time for his knowledge), but - hopefully - the service centres know what to do, and a recalibration of the camera is enough to fix it.

Tohru Kodama
15:17 (1 ora fa)
a me

Internal

Dear Mr. Irlanda,

After further discussions there have been a few cases in Asia and each time sending the camera to a service centre for adjustment will fix the problem. It is still unknown what causes the magenta banding and not possible to replicate as the problem occurs only on cameras which require the adjustment.

Recommend that you send the camera to LTR so that they may check and make the necessary adjustments/calibration.

Last edited by MarkJerling; 07-28-2019 at 05:52 PM. Reason: e-mail address removed.
07-28-2019, 05:41 PM   #21
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I haven't noticed this myself, but I'll test after my batteries are done charging.
07-29-2019, 12:25 PM   #22
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QuoteOriginally posted by Éire69 Quote
Dear Mr. Irlanda,

After further discussions there have been a few cases in Asia and each time sending the camera to a service centre for adjustment will fix the problem. It is still unknown what causes the magenta banding and not possible to replicate as the problem occurs only on cameras which require the adjustment.

Recommend that you send the camera to LTR so that they may check and make the necessary adjustments/calibration.
Good to see that your problem has been reported by other owners and that it is addressable by routine calibration.


Steve
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