In rec.photo.digital Willarojo <macrophotog@[EMAIL PROTECTED]
> wrote:
> PixelPix <mail@[EMAIL PROTECTED]
> vehemently accused in
> news:162f4967-3904-4857-b61d-9cceea6a956c@[EMAIL PROTECTED]
> com:
>> On Apr 13, 12:35 am, Willarojo <macropho...@[EMAIL PROTECTED]
>
>> wrote:
>>> "Rita Berkowitz" <ritaberk2...@[EMAIL PROTECTED]
> vehemently accused
>>> innews:YsmdneCCFrE4gGTanZ2dnUVZ_qvinZ2d@[EMAIL PROTECTED]
>>> >> Maybe I just don't understand but everything I've read and
>>> >> witnessed leads me to believe that the WB setting doesn't do
>>> >> anything at all to the image data in the raw file.
>>>
>>> > You, like many others, erroneously assume RAW data is just
>>> > that, 100% unprocessed data from the sensor, it is not. WB
>>> > is calculated into setting many different camera parameters,
>>> > even simple ones such as how the camera exposes an image.
>>> > True, you can always change this is post, but at a cost. Set
>>> > you WB so you can intentionally blow your blue channel and
>>> > come back and tell what you find after you correct it in
>>> > post. You get more leeway with RAW than using JPG, but you
>>> > are still not getting a free lunch shooting RAW. That is why
>>> > it is so im****tant to get it right in-camera.
>>>
>>> > Rita
>>>
>>> Is it too late to jump in on this one?
>>>
>>> I read the article in "ppmag" and I have a question: is the
>>> author suggesting that because changing the color/WB sliders
>>> while manipulating a RAW file is the same as (or at least
>>> comparable to) varying the WB settings that were set when the
>>> RAW was taken? Is she suggesting that post-shot processing is
>>> directly comparable to shot-taking settings? Am I
>>> misunderstanding this? I mean, she is comparing 2 different
>>> conversions/manipulations of 1 RAW file, not comparing multiple
>>> RAWs and RAW settings, right?
>>> May I propose a (hopefully) rigorous way to examine this:
>>> take
>>> a series of shots of the same object/scene in the exact same
>>> lighting conditions, but in every "basic" WB setting. In fact,
>>> we could go further and do the same thing for every Kelvin
>>> increment setting, I think.
>>> If the RAW histograms are all the same, then WB does not
>>> affect
>>> RAW exposure; if they vary, then WB does affect exposure. We
>>> could even estimate how much they affect exposure.
>>> So, is WB metadata that is recorded at exposure, but does
>>> not
>>> directly affect; or is it a "mask" that is recorded *and*
>>> applied at exposure?
>>> I don't have the answer, but this clearly is an im****tant
>>> issue, and I certainly would like to know, so I can set my
>>> camera properly, depending on what I hope to accomplish at any
>>> given shoot.
>>> Or do all y'all want to continue with the sniping, which I
>>> must
>>> say is terribly clever and entertaining. (Not really.)
>>>
>>> Willa
>> The test that you have suggested has been conducted and re****ted
>> on two or three times throughout this thread and WB has made
>> absolutely no difference to exposure while shooting RAW, as the
>> histograms have remained identical.
> That's what I found in my own half-assed attempt at the same
> experiment.
> So, the rest of the thread is fluff, neh?
Unless not all cameras behave the same with respect to WB and
RAW. Unlike jpeg RAW isn't a public standard, it's just a generic name
for the entire caboodle of what different camera output as their least
processed closest to sensor data encoded image files. Not only do
different makers produce different kinds of RAW files, but most of
them try to keep exactly what they do a trade secret.
--
Chris Malcolm cam@[EMAIL PROTECTED]
DoD #205
IPAB, Informatics, JCMB, King's Buildings, Edinburgh, EH9 3JZ, UK
[http://www.dai.ed.ac.uk/homes/cam/]
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