Raw and white balance, picture style etc.

<p>This is a question which I suspect is common, but I don't know the answer. If you shoot raw, which I always do, do things like color balance, picture styles etc matter at all? Does ACR take into account whatever the white balance was at exposure? Or does ACR start over with the data regardless of camera settings? <br>

Experience tells me that setting white balance is important. For instance when doing a panorama, if I don't set the white balance to daylight, as opposed to AWB, the exposures for the panorama have a color shift when opened in ACR.<br>

Thanks.</p>

<p>From my experience with this I find setting WB can be crucial when shooting scenes lit by light that is farthest away from the ideal D50 illuminant with regards to spectral distribution quality, the subject shot and the color cast produced.</p>

<p>All appearances of WB viewed in any Raw converter is strictly interpreted. There is no real correlation between the color cast seen and color temp number assigned or if anything that's intended to look neutral will wind up exactly R=G=B in the Raw converter.</p>

<p>There are other optical issues associated with color cast perception that go beyond numbers and appearances of a neutral object. Switching between Picture Style camera profiles will show you color table shifts in the "Pixel DNA" of the image that play with perception in this regard.</p>

<p>Incamera AutoWB goes so far in correcting like say sunsets and 2800K tungsten scenes which an incamera preset (custom or canned) will work better in fitting the color gamut of scenes lit like that especially in order to control saturation like say yellow, orange and red flowers. Raw converters deal with (interpret) these extreme off WB type scenes in different ways even if you use the correct exposure.</p>

<p>John, DPP should correctly interpret all your settings for RAW if that's what you want to use. I don't, I use Lightroom, which has a similar processor to the current ACR. However, you can use presets in Lightroom for different Canon settings.</p>

<p>ACR should correctly show the WB set at the time of exposure. Since you're shooting in RAW, that's not a big deal, you can just use the settings in ACR to make it what you want. That color shift you reference means that you can just change the WB. Once again, in Lightroom, you have pull-downs for standard situations, but I'm not sure if those are in ACR.</p>

<p>You'll have to control color cast mismatches by eye for pano's for ACR. Maybe you could use a dedicated pano stitch software that does everything automatically. I can't tell much more about that because I've never done panoramic shots.</p>

<p>But I do know what you're up against in getting the color casts to match up so color like skies look seemless. See below how ACR interprets and/or the sensitivity of my incamera AutoWB in the two screen shots. To get the shaded barn to match up between the two images I had to adjust by eye.</p><div></div>

<p>Tim, you're using a brand and model of camera that the OP does not use. Conclusions cannot be drawn from that, it's just not a very scientific result. It's possible that John's Canon with ACR gives better results, or that his Canon with Canon's DPP software can give better results.</p>

<p><em>"If you shoot raw, which I always do, do things like color balance, picture styles etc matter at all?"</em></p>

<p>No they do not. Some camera settings do affect RAW capture information, HTP and long exposure noise reduction to name two, but WB and picture styles do not, they do not affect the RAW information recorded.</p>

It you shoot RAW and use Bridge, WB makes no difference.

 

If I shoot RAW I never bother using anything other than AWB.

 

For starters, the AWB is already quite good with my camera so whatever adjustements needed in post are trivial.

 

But you mentioned panoramas. Here you can stack all the images from Bridge and into ACR, and then select "use same WB

for all images" or something like that. This will give you the same blue in the sky. In anycase, the Photomerge (auto) funtion will

blend and smooth the skies, so if you have overlapped 30% or more there should be no problems.

 

As a side note, you can make decent enough adjustements to the WB for the overwhleming majority of JPG files in ACR.

This shool of thought that everything needs to be shot in RAW to adjust the WB is just plain wrong.

<blockquote>

<p>Tim, you're using a brand and model of camera that the OP does not use. Conclusions cannot be drawn from that, it's just not a very scientific result. It's possible that John's Canon with ACR gives better results, or that his Canon with Canon's DPP software can give better results.</p>

</blockquote>

<p>No ones' being scientific here, Jeff. That's the point of this. It's not scientific. WB appearance could be any color of the rainbow when it comes to matching exactly in providing a seamlessly stitched panoramic. Slight WB variations are mainly noticed when trying to match wide flat swaths of sky color which the eyes pick up on over like say the slight WB differences in textured objects like trees, grass and mountains.</p>

<p>The image sample I posted was to illustrate how slight changes to focal length, angle of lens to light source can influence any camera's AutoWB even when shooting the same scene using the same light. I didn't say the OP's camera was like my camera, but I did want to point out the potential or errors just lined out. With my camera it could be caused by ACR itself because I don't have another Raw converter to compare against. The OP does.</p>

<p>The OP is expressing a need for exactness in WB appearance in stitching pano's and he hasn't made this clear with his camera. And it really wouldn't make a difference anyway because it's the Raw converter that makes the final decision, not the camera's hardware. It will come down to a question on whether one Raw converter delivers desired color appearance but less consistency compared to the other that provides the opposite. I'ld go with the one that requires less stitch blending because it's far more easier to get the desired color.</p>

<p>I'm having to assume this is the reasons for his specifics on tying WB color temp numbers to appearance which is interpreted by the Raw converter. Maybe Canon's DPP interprets WB appearance better or worse than ACR which was what I was making assumptions upon.</p>

<p>In fact a while back in an Adobe ACR forum I was attempting to troubleshoot why a poster was not getting R=G=B numbers shooting a spectrally flat neutral commercial WB target with his Canon's AutoWB. ACR was showing the target with a very blue bias shooting the target in direct sunlight at noon.</p>

<p>I couldn't understand this because I posted my Pentax K100D shots of my WhiBal target, also a spectrally flat neutral target, under the same direct sunlight and got perfect R=G=B numbers in ACR with Kelvin numbers ranging around 5000K/Tint around +3-5, but never with consistent appearance <strong>(in other colors/neutral always looked spot on)</strong> shot to shot of the same scene under the same light.</p>

<p>Another poster piped in and suggested their may be a firmware fix in store for that particular Canon model. It was never confirmed that that was the problem. But it was also never confirmed to be an ACR WB interpretation problem either.</p>

<p>But I'm just putting that out there because that Adobe forum poster raised the same concerns about tying the Kelvin number to the appearance of WB as a way to achieve consistency shooting in uncontrolled outdoor sunlight and so I offered the answer I gave.</p>

<p>Digital cameras are not precision scientific instruments and neither is the software interpreting the sensor data.</p>

<p>When shooting raw the settings (wb, picture styles, processing parameters, etc...) applied by the in-camera processing are not permanent, and can be adjusted as you wish later in the raw processing software of your choice. </p>

<p>Those settings do affect the jpeg displayed on the camera LCD though, and the histogram you are shown is based on that jpeg. For instance increasing contrast or saturation in-camera can cause the histogram to indicate blown highlights, when actually the raw file is fine.</p>

<blockquote>

<p>And it really wouldn't make a difference anyway because it's the Raw converter that makes the final decision, not the camera's hardware.</p>

</blockquote>

<p>This is what you're missing. If he wants the camera's WB, he can get it with DPP, which is Canon software. DPP reads the camera settings and applies them to the RAW file, identically to the way it shows on the camera. So for the default on import, you get what the camera decided. </p>

<p>Once again, if you were familiar with Canon's software, this would be clear.</p>

<p>Jeff, I realize the OP can get the camera's WB in DPP.</p>

<p>I'm referring to acquiring consistent appearance of WB in a series of shots later to be stitched into one panoramic shot. Consistency in a series of shots taken this way AND desired color are two separate things where you may not get both with one or the other Raw converter.</p>

<p>Not only that but as you take a series of shots one after the other as you pan the camera across a wide area you may or may not get slight variations in sky blues shooting with AutoWB due to changes in UV/IR the camera's WB metering picks up due to the position of the sun in relation to the lens.</p>

<p>I'm not saying this is the OP's case, but the fact that <strong>he's associated Kelvin numbers with WB appearance</strong> indicates he's not getting desired results and is expecting the camera and Raw converter to nail the numbers and the appearance with every shot at certain level of precision. I really doubt this level of precision is available with any consumer level camera.</p>

<p>Maybe John Hennessy will post back with further details.</p>

<p>Here's that Adobe Forums Canon 50D WB issue I referred to in my previous post:</p>

<p>http://forums.adobe.com/thread/516436?tstart=90</p>

<p>That's a couple years old, and a lot of the people on that thread think there isn't a problem.<br>

<br />However, I still recommend that the original poster try DPP (it comes with the camera) and see what happens. It renders differently than ACR or LR and it's not sensible not to try it. It's a free solution if it works.</p>

<p>John,<br>

When you open a RAW file in ACR, the development module shows a value for color temperature and the indication "as shot" for white balance. So, it shall take your camera setting to some extent - I don't know if in full accordance to the one you set or some value calculated according to the internal algorithms of ACR, but it seems to "use" that value.<br>

On the other hand, all your camera settings go together with and annex to the RAW file information and how far this is taken into account will depend on the converter you use, and the version of that converter as you can not exclude that a new version will change the rules of the game.<br>

However, no matter what happens at present time you are free to change the white balance at will, because what you see at first is just one of its possible interpretations - either respecting the camera settings of calculated according to the software internal algorithms. And keep in mind that both AWB or a value you set can either be precise or just a value with a certain degree of variation.<br>

What happens with the panorama is just to be expected as the camera guesses the WB for each click and when you move the camera for the next one the light conditions change. But, even if you use AWB you can open all the files in ACR, calculate the white balance for the most significant area (in one file and for the all area covered by the panorama) and apply this to the other images (ACR allows you to do it as a batch regulation).<br>

And this is valid not just for WB but also for other camera regulations or the ones you ask ACR to use for the first image.<br>

Finally, the most important is the final white balance you end up with, but if you get it right from the beginning it will make things easier for you.</p>