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Re: White balance in RAW - necessary ?
Old 06-18-2007, 11:09 AM   #6 (permalink)
rolandogomez
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Over the years, I've seen many arguments about this, part of the problem, most of the data out there today, even by Adobe today, is based "after" the fact--when the RAW file is placed in a RAW converter program, usually proprietary to that camera's manufacturer, and/or in a program like Lightroom or some image editing program with a RAW converter or bridge. Thanks to marketing, we are "pigeonholed" into RAW methodology based on post-production not pre-production.

Most what you'll find on the net is based on the latter--once you get it in the program by importation and that white balance doesn't matter--again, after the fact.

What you have to find with thorough research (remember the Adobe/Nikon spat) is what happens "before" in the camera itself based on all those RAW formats, like NEF (Nikon), OLY (Olympus), CR2/CRW (Canon), Fuji RAF, etc. Ever wonder why the much pushed "DNG" format by Adobe is barely adopted and the latter three camera companies have not adopted what Adobe pushed for the digital "standard" negative? Part of the problem with RAW today is that the major camera companies also realize there is money in software--hence Nikon Capture, Olympus Studio, Canon FileViewer etc., etc., etc. It's this software that interprets their RAW format based on how they wrote their RAW program that is inside the camera. These companies also tout, "My RAW is better than your RAW." The only thing today that is a "standard" (file format) for images is jpg's, TIFF's, just like "LAB" color is to color management (think ICC profiles).

What I've also found, mainly from those with Phd's in some photo science, physics or engineering is that, true, once you have the RAW file in a program outside the camera you can adjust it all you want, but it's what happens inside the camera during the shoot that matters and every camera manufacturer will process RAW differently--remember the Nikon stink with white balance encryption with the D2x that pissed so many people, including Adobe off? Also, you can take a Canon, Nikon, Fuji, Olympus, Sony, etc., put them all on tripods with the same lens equivalent, all set on RAW, all set to the same white balance defualt (think AWB) all set on the same shutter speed and aperture pointing at the same scene and click the shutters at the same time, and they will all give you different results of white balance color, even when all set to RAW when you export the images out of the camera without any adjustments.

Ultimatley everything is based on algorithims, the rounding off of numbers as the ultimate result. Personally I like to "get it right" and the white balance, even in RAW, will show up correctly during the preview (chimping). I don't want to make "guesses" (or have the camera's software do it for me) after the fact, I want it the way I captured it, or envisioned it, and I want the proof on the spot. Keep in mind, RAW and JPG have "improved" over the years with better algorithims, it's a constant changing world. Technology changes every Monday when the Board of Directors meet. And let's not forget, we used to look at images for what they were, knowing what we shot; today, with digital, we look at what can be done to the image--are you an imagemaker or a photographer?

According to Mikkel Aaland and Jack Holm in Aaland's book, Shooting Digital, during the capturing of an image during the RAW process itself, "White balance is determined and applied. (Data that isn't deemed useful is discarded.)" The determined comes from their software algorithims--again, they vary with each manufacturer.

In addition, he further states, as all RAW's are not created equal by each manufacturer (based on propriety software of brand using algorithims), that during the RAW process itself it goes through device color, then scene color, then picture color and that, "The results are only as good as the capabilities of the camera."

Further, in a "note" box, he states, "Not all RAW data is losless. Some manufacturers offer a compressed RAW file which reduces the file size but can slightly degrade the image. Other manufacturers may offer "scene" data in the form of a TIFF RGB file, sometimes calling it RAW. Scene data can be viewed without special RAW software, and has already been white balanced. However, once white balancing has been preformed, re-adjusting it will cause loss of highlight information." (Now where does "readjustment" take place once outside the camera?)

They also state, "Why are these color transformations necessary? The human visual system doesn't see or process color the same way the camera (or "device") does. The transformations are attempts to convert red, green, and blue data into a form that more closely duplicates what we might see if we viewed the scene directly." (Remember, each camera manufacturer has different, proprietary formulas here.)

Now, a note on the two people I'm quoting here, Aaland, a photographer, writer and author of several photo books as early as 1992 with Random House, has had his images exhibited around the world from Paris to Prague. He's consulted for the Washington Post, Newsweek, Wired, American Photo, and many others and has held workshops at Berkeley, Stanford, Drexel, UC, and even a guest speaker at Photo Plus.

Holm, a former professor at RIT, is also a senior scientist at Hewlett Packard who has worked and published extensively on on RAW data, both in and out of the camera and was also a color science consultant for NASA, Kodak and Polaroid. HP credits a lot of what you see in digital today because of him. He also worked with the ISO committee to set standards for digital photography, a member of the ICC work group and is chair of the USA Technical Advisory Group for ISO TC42 (Photography).

Now, if you read this far, I appluad you, you are dedicated and passionate about your photography to the end. Don't get caught up in the marketing hype (think Adobe wanting to have a digital file format standard, DNG) that has convinced the photographic world that you can "fix" it in RAW--a lot of "fixing" is going on in the camera during the RAW interpolation of data as it's being written to that digital card.

There's even arguments about RAW vs JPG where the human eye cannot tell the difference between the final images, on screen, and prints on paper, between the two if the JPG is handled correctly right out of the camera before any post production--I've tested this myself and when done properly you cannot tell the difference by merely looking at the image on your monitor on in a magazine or book or print. Remember, JPG is a known standard that is done the same in software, cameras, etc. Now that alone is worth a different thread.

One final note--yeah, you can say just shut-up and shoot--but ultimately it's your final image that reflects your abilities as a photographer and understanding your camera and how it works can sometimes make a helluva difference. Ultimately it's the workflow that works for you--my workflow is get it right in the shoot, don't rely on Photoshop as the crutch. In the days of film, we had no imaging software program to save us, we changed film emulsions (think white balance here) and developing techniques if necessary, perhaps that's why I shoot like I do.

Oh well, back to catching up to emails and PM's, thanks, rg sends!

(This image of Yvonne is shot with a white balance of 4000K, in the camera. Lighting, by Hensel Integra Pro 500 monolights had a Hensel Beauty Dish with two 3/4 CTO's on the front. Image shot in the jpg standard and the colors were "nailed" right there. Camera was the Olympus E-500!)
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Re: White balance in RAW - necessary ? 
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