Any idea what these strange streaks are?

SterlingBjorndahl

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GFX 100S with the 35-70. These streaks only appear in the RAW file (using ACR) not in the SOOC jpeg.

100% crop of the affected area:



 100% crop - the horizontal streaks appear in ACR processed RAW file but not in ooc JPEG
100% crop - the horizontal streaks appear in ACR processed RAW file but not in ooc JPEG



Reduced full image (minus crop of boring foreground) with the affected portion circled. The sun is coming from the left, slightly backlit:

23181e71fdb74909ba5718b73c660a17.jpg

Thanks,
Sterling
--
Lens Grit
 
Solution
That works.

9ee9aae06acc487bb509fa9a4c757f3c.jpg.png

All four channels are blown. All bets are off then.
In my book, it is OK to blow irrelevant highlights. The "leakage" of blown highlights into shadows in the form of stripes is strange.

P.S.: it occurs with LrC and C1.
Histogram of the area with problems:

7ffedc52b4bb42be97d94bf3d2f753a6.jpg.png

ACR defaults
ACR defaults

+100 shadows
+100 shadows

+100 shadows, blacks
+100 shadows, blacks

+100 shadows, blacks; -100 whites.
+100 shadows, blacks; -100 whites.

This could be PDAF striping. I would suggest not blowing highlights adjacent to dark areas that you may wish to boost.

--

https://blog.kasson.com
Please provide a link to the raw file.
 
Last edited:
That works.

9ee9aae06acc487bb509fa9a4c757f3c.jpg.png

All four channels are blown. All bets are off then.
In my book, it is OK to blow irrelevant highlights. The "leakage" of blown highlights into shadows in the form of stripes is strange.

P.S.: it occurs with LrC and C1.
Histogram of the area with problems:

7ffedc52b4bb42be97d94bf3d2f753a6.jpg.png

ACR defaults
ACR defaults

+100 shadows
+100 shadows

+100 shadows, blacks
+100 shadows, blacks

+100 shadows, blacks; -100 whites.
+100 shadows, blacks; -100 whites.

This could be PDAF striping. I would suggest not blowing highlights adjacent to dark areas that you may wish to boost.

--

https://blog.kasson.com
 
Last edited:
Solution
That works.

9ee9aae06acc487bb509fa9a4c757f3c.jpg.png

All four channels are blown. All bets are off then.
In my book, it is OK to blow irrelevant highlights. The "leakage" of blown highlights into shadows in the form of stripes is strange.

P.S.: it occurs with LrC and C1.
Histogram of the area with problems:

7ffedc52b4bb42be97d94bf3d2f753a6.jpg.png

ACR defaults
ACR defaults

+100 shadows
+100 shadows

+100 shadows, blacks
+100 shadows, blacks

+100 shadows, blacks; -100 whites.
+100 shadows, blacks; -100 whites.

This could be PDAF striping. I would suggest not blowing highlights adjacent to dark areas that you may wish to boost.
Bloody PDAF striping. I wish MF cameras were without PDAF.

OP's framing is not exotic; it is quite a typical framing. I wonder if it is reproducible or if it happens very rarely.
 
OP's framing is not exotic; it is quite a typical framing. I wonder if it is reproducible or if it happens very rarely.
Yes, that's why I brought it up - I feel that I've taken dozens of shots like this and never noticed this problem before so it really surprised me, so in my experience it's not (yet) reproducible and indeed is rare.

But maybe I haven't blown the highlights and boosted the shadows quite as much in those other shots. And if it's related to the PDAF sensors then maybe this shot was just the bad luck of the draw and if I'd angled the shot a degree differently it wouldn't appear. But I think Jim is correct that when the highlights are blown like that, there are no guarantees.

Thanks,
Sterling
--
Lens Grit
 

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