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11-19-2017, 03:11 AM   #16
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QuoteOriginally posted by StanT Quote
Thanks, one would think so, but the images are 1 after the other so if there was a setting issue it would be consistent. The DNG files look just like this. even 10 sec apart two different colors cast 1 normal 1 magenta.
If cross processing is turned on, the results would NOT be consistent. Well, I'll admit that I'm not sure if cross processing affects the DNG file or just JPG.

11-19-2017, 03:46 AM   #17
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QuoteOriginally posted by pentaxfall Quote
I read that DNG file stores processed a JPEG image and also raw-image. Many image viewers show the processed JPEG (embedded inside DNG) instead of rebuilding the image out of raw-data. This is for s/w optimization. So try generating JPEG from DNG, see if that JPEG is any good.

DNG file format is able to store multiple images. Here is an another example. In case of in-camera HDR the final DNG will be a large file, and it will have the raw files used for HDR. DCU5 tool is able to extract the original raw files. In fact this feature of DCU5 saved the day for me.
Good Call, that is correct the embedded Jpeg is what you would see. The fact is the raw DNG files have the color cast. which I correct for when processing the raw file. Here is the image
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11-19-2017, 04:48 AM   #18
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QuoteOriginally posted by StanT Quote
I am new to Pentax and the K1 and to be honest have never seen this with my Nikon gear after shooting weddings for 20 years.
I've never seenwhat you experience with any Pentax cameras I owned for the last 20 years, Pentax K1 included.

---------- Post added 19-11-17 at 12:51 ----------

QuoteOriginally posted by StanT Quote
The fact is the raw DNG files have the color cast.
DNG file from a healthy sensor / camera, are not affected by white balance.
11-19-2017, 06:01 AM   #19
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QuoteOriginally posted by biz-engineer Quote
I've never seenwhat you experience with any Pentax cameras I owned for the last 20 years, Pentax K1 included.

---------- Post added 19-11-17 at 12:51 ----------


DNG file from a healthy sensor / camera, are not affected by white balance.
I agree the raw files are just that, raw. Yet how to explain this?

---------- Post added 11-19-17 at 06:03 AM ----------

This only occurs when there is a large amount of red in the image.

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11-19-2017, 06:10 AM   #20
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Here is the file info in Aperture
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11-26-2017, 06:27 AM   #21
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I have expirienced similar problems. The AWB does not work consistent and it happens, that the pink color cast appears like shown above. I have the problem, as well when green trees are in the background. But it also happens under varying lighting conditions. The basic color tint is more towards pink than yellow like the Nikon AWB uses to be. Often skin tones do look like Miss Piggy.
11-26-2017, 10:54 AM   #22
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QuoteOriginally posted by StanT Quote
I agree the raw files are just that, raw. Yet how to explain this?

---------- Post added 11-19-17 at 06:03 AM ----------

This only occurs when there is a large amount of red in the image.
In simple words: AE systems tries identify "grey-to-white" areas in the frame to identify color temperature before making shoot by reading data from exposure metering sensor. Exposure metering sensor has restricted number of metering areas (AE sensor contains only 86k RGB pixels in comparing 36M pixels in main sensor in K-1).

Returning to your pictures: there are almost no grey or white colors in your image. AE system tried to find areas where differences between R,G and B levels is minimal to identify them as "grey or white".

P.S.
Of course AE metering algorithm is more complex than in my description. But common idea is there.

P.P.S.
Different vendors may use different additions to algorithms in own AE modules. As I remember, Nikon uses many predictions based on real image database in own algorithms.

Last edited by tregubovav; 11-26-2017 at 11:15 AM.
11-26-2017, 12:08 PM   #23
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Thanks, I did some research as well and came to the same conclusion. I only brought this up as I have not seen this behavior where 2 photos with in seconds of each other in the exact same conditions would have two very different color profiles. even if only the JPEG embedded in the raw file.

I currently shoot Leica Q, Oly EM1- Fuji X100 F and Nikon which I have since left for the Pentax. I have not seen this occur in these systems There is no question mixed lighting has a big impact on AWB, since I shoot raw I never concern myself with the WB as it is easy to correct for in PP.

In this case the conditions were more or less controlled, which is why I started asking these questions. Thank you everyone for your input.

Of all the forums I have belonged to this one is by far the best experience, Thank you.

11-29-2017, 07:02 AM   #24
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It's called colour failure and it happens when there is a predominant colour cast in the picture.
12-04-2017, 08:05 AM   #25
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I have never seen quite what you have in your barn door shot, but I have seen that the reds can be over-saturated if there's a lot of red in the frame. At times I wonder if the Pentax exposure metering is "blind" to red. A bit of negative EV comp seems to help in those instances, although that would hardly do much good with your examples.

QuoteOriginally posted by StanT Quote
Of all the forums I have belonged to this one is by far the best experience, Thank you.
I wholeheartedly agree. Members here are eager to help, even when the questions asked are far less concisely put than yours.
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