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07-15-2013, 02:05 PM   #16
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QuoteOriginally posted by stevebrot Quote
both red and yellow have traditionally been a challenge for digital sensors (regardless of brand) in that any degree of saturation tends to result in loss of detail and color "blocking". The problem is intrinsic to the system and cannot be remedied in PP. This happens with RAW as well as with in-camera JPEGs.
It is not so much sensor limitations but subsequent processing and display. Everything in this shot is outside sRGB or Adobe gamuts, yet there is no clipping in the RAW, it is actually over a stop underexposed




The RAW is here, if anyone wants to play with it.


Last edited by kh1234567890; 07-16-2013 at 02:56 AM.
07-15-2013, 04:55 PM   #17
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Here's some more info..... I tried some additional shots and found a couple observations:

1) Red from OOC JPEG engine, in either Natural or Bright, takes on a slight pink/blue cast compared to the RAW image. If you PP the JPEG and selectively move the pink slider from center toward red (away from blue), the red rendering of the OOC JPEG comes into alignment with the RAW image.

2) The blurred reds on the OOC JPEGs don't happen all of the time. A piece of red fabric shot with natural to cloudy light and relatively low ISO has excellent detail in the OOC JPEG that rivals the RAW image. Take the same subject and shoot it under tungsten light (this time ISO 3200), the OOC JPEG loses much detail while the RAW still holds excellent detail.

I'd post some of the shots but out of time.
07-16-2013, 02:01 PM   #18
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QuoteOriginally posted by kh1234567890 Quote
yet there is no clipping in the RAW
You must mean that there is no clipping in the TIFF or the rendered RAW on screen. As for this particular JPEG, there is clipping in both the red and yellow. It is just harder to see on the smooth shiny surface of a pepper. For a more challenging test, I would suggest something with high saturation and high detail, say flower petals or fabric swatches for example.


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07-16-2013, 02:50 PM   #19
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I know all cameramakers say they can make images at iso 12.600, but honestly your best images are still made at iso 100! Using iso5000 and having hi expectations will be a good rescepy for disapointment.

07-16-2013, 03:11 PM   #20
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Just shot these a few minutes ago of a rose in our front yard. The first image file is based on the RAW image and is a straight JPEG output from Aperture without modification. The second is OOC JPEG using Natural as the color profile.
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07-16-2013, 03:27 PM   #21
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And here are the shots of the rose taken at -1 EV. As before: first image is JPEG converted from RAW image in Aperture followed by the OOC JPEG (Natural).
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07-16-2013, 03:32 PM   #22
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QuoteOriginally posted by stevebrot Quote
You must mean that there is no clipping in the TIFF or the rendered RAW on screen.
No, there is no clipping in the raw data - all four channels have maximum values well below 4095 (it was taken with a 12 bit K-7).
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07-16-2013, 03:35 PM   #23
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And lastly, shot at -2 EV. First is JPEG converted from RAW in Aperture, second is OOC JPEG (Natural). What's not obviously apparent in these shots as seen here is the fairly dramatic difference in detail seen on my computer screen between the RAW and OOC JPEG. Details in the rose (not the green foliage) is very blurred on the JPEG but still there in the RAW.

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