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Thread: ACR: Highlight Clipping Warning

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    Default ACR: Highlight Clipping Warning

    Hi all,

    Since I switched from DPP to ACR for raw conversion I very often get comments that my whites in the images are hot/too bright although no highlight clipping warning is indicated in ACR. I understand that upon subsequent processing and preparation for web display the whites may get hotter but that is independent from the raw conversion and such effect should apply to both DPP and ACR.

    One option DPP offered was to set values for the highlight clipping warning other than 255, e.g. I think I used 250 or even 245 in DPP. That seemed to ensure that there is sufficient space for subsequent processing but still get good whites. Does anyone know if that is possible with ACR?

    Thanks. Best, JR

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    Joerg,

    I've researched your question and can not find an answer. Perhaps another member has an idea.

    Roger

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    I don't know the answer either, but I have observed that jpeg conversion can cause problems. For example I've been careful in ACR to take care of clipping, opened in PS and checked again. No problem. Then I resize and convert to jpeg and post the image, not checking if clipping has occured since everything seemed OK previously. I didn't think it necessary to check. Then I get feedback about blown channels and clipping, which didn't seem right, so I downloaded my own image and checked it and it was indeed true!!
    Of course I don't really care if thejpeg has clipping; the important thing is that the full sized un-compressed image is alright. regards~Bill

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    Quote Originally Posted by WIlliam Maroldo View Post
    I don't know the answer either, but I have observed that jpeg conversion can cause problems. For example I've been careful in ACR to take care of clipping, opened in PS and checked again. No problem. Then I resize and convert to jpeg and post the image, not checking if clipping has occured since everything seemed OK previously. I didn't think it necessary to check. Then I get feedback about blown channels and clipping, which didn't seem right, so I downloaded my own image and checked it and it was indeed true!!
    Of course I don't really care if thejpeg has clipping; the important thing is that the full sized un-compressed image is alright. regards~Bill
    Bill,
    Are you converting to sRGB when you convert to jpeg, from a larger color space, like Adobe RGB? If so, that is the cause of the blown channels. If you have a nicely balanced image in the histogram in aRGB then convert to a color space with a smaller gamut, like sRGB, then some colors will not fit and get clipped, both highs and lows in the conversion.

    Roger

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    Thanks Roger! You nailed it, I convert from Adobe RGB to sRGB in the Save for Web and Devices dialog box and the smaller gamut does it.

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    Robert Amoruso
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    Looks like your question has been addressed William but to expand.

    I guard against that in ACR by not pushing white to the limit. Also, in PS in a levels correction you can set whites lower.

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    Thanks for the information

    Ray

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    Quote Originally Posted by Roger Clark View Post
    Bill,
    Are you converting to sRGB when you convert to jpeg, from a larger color space, like Adobe RGB? If so, that is the cause of the blown channels. If you have a nicely balanced image in the histogram in aRGB then convert to a color space with a smaller gamut, like sRGB, then some colors will not fit and get clipped, both highs and lows in the conversion.

    Roger
    Actually, I've seen this happening also upon preparing for web presentation if the image already was in sRGB. But I agree that converting from aRGB should amplify the problem. JR

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    Thank you all for taking the time to comment. And sorry for my late reply.

    Robert, what do you mean by "in PS in a levels correction you can set whites lower"? I am guessing you're referring to adjusting the white point in levels but not sure... JR

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