Odd White Balance results with Grey/White Card - Tips Please

[brucetheamateur]

<p>Canon 5D MKII, 24-105L w/ out of the box settings<br>

I usually shoot RAW but always have issues with proper white balance (WB). In general, the auto-WB on the 5D MKII does an OK job but not perfect – I almost always tweeze it up a bit. So, I followed some advice and would shoot a first pic with a gray card and then adjust subsequent photos in Canon's Digital Photo Professional (DPP) afterwards using the “Click White Balance” to then adjust the rest. Well this just results in disaster in my opinion. So…. What the heck am I doing wrong here?<br>

I just shot the following pic in RAW with auto white balance selected (ISO 100, Standard style) and am holding a gray card and white card in each hand. Then in DPP, I converted one image directly to JPG with no adjustments, the second and third, I used the “Click White Balance” on the white and grey cards and output a JPG for each. The most accurate is the auto white balance. The click-on-white card is way too green, and the click-on-grey is way too red. In my experience, the gray card produces awful results and a white card does much better but auto with my own tweaking is best. What’s up with this?<br>

Click on the links for the original RAW and larger images of what you see here (change xx to tt).<br>

<a href="http://mywebpages.comcast.net/brucedebonis/5DMKII/Test.CR2">http://xx/5DMKII/Test.CR2</a><br>

<a href="http://mywebpages.comcast.net/brucedebonis/5DMKII/TestAutoWB.JPG">http://xx/5DMKII/TestAutoWB.JPG</a><br>

<a href="http://mywebpages.comcast.net/brucedebonis/5DMKII/TestClickGry.JPG">http://xx/5DMKII/TestClickGry.JPG</a><br>

<a href="http://mywebpages.comcast.net/brucedebonis/5DMKII/TestClickWht.JPG">http://xx/5DMKII/TestClickWht.JPG</a><br>

Below is AWB / Click Gray / Click White<br>

<img src="http://mywebpages.comcast.net/brucedebonis/5DMKII/TestAutoWBsm.JPG" alt="" /></p>

<p><img src="http://mywebpages.comcast.net/brucedebonis/5DMKII/TestClickGrysm.JPG" alt="" /></p>

<p><img src="http://mywebpages.comcast.net/brucedebonis/5DMKII/TestClickWhtsm.JPG" alt="" /></p>

[janne_moren]

You may take a look at your monitor. To me the first one is too cold, while the second is well balanced. The third looks good too, if just a little green.

 

First, are these real grey and white cards, or just something grey and white you picked up around home? White, especially, tends to have a color cast of its own; if the "white" is really very lightly red-toned, the resulting white balance will be shifted like this. Get real white and grey swatches from an art store or similar to make sure you have neutral sources.

 

Second, you're standing in shade, with a bluish sky and greenish surroundings. Which is the light that the grey card sees, and will compensate for. That will result in a fairly warm cast - if you set your camera WB to "shadow" or "cloudy" you'll get a similar warm cast to your images.

 

And lastly, again, the second image is the one that looks most right to me - I would perhaps cool it just a touch, or keep as it is. The first one looks the most wrong, with a cold, blue tone.

[digitaldog]

<p>The first may appear too cool but I’ll bet you the white and gray values are pretty neutral. </p>

<p>WB is season to taste! Especially with raw where the WB settings have zero effect on raw data. Its just a metadata suggestion for the converter, each will do a different job. What’s nice about the X-Rite ColorChecker Passport tool is you have a row of warm and coolish WB tiles along with the spectrally neutral one and you can click on them to affect the WB to taste which is often necessary. </p>

[brucetheamateur]

<p>Good responses. Thanx.<br>

Coupla Items:<br>

1 - I purchased the white and gray card from photo stores and are purposed for just this usage.<br>

2 - I calibrated my monitor with a Spyder 3 callibration tool a few months back and surprisingly it was pretty spot on. The monitor is around three years old so I suspect it is stable (a Gateway 34" HD unit)<br>

3 - Regarding the 2nd photo, the one set with gray card: How does the red tail lights and flowers look to you? They look a bit over saturated with too much red to me. My shirt looks like it is glowing and while it is a bright orange shirt, it just doesn't look natural to me.<br>

4 - Yes, the first photo, camera's auto white balance, looks a bit cool to me also.<br>

But the big issue, to me, is that if the camera is doing its job of determining proper white balance, and gray and white cards are valid ways of determining proper white balance, shouldn't they all look the same?</p>

<p> </p>

[digitaldog]

<blockquote>

<p>But the big issue, to me, is that if the camera is doing its job of determining proper white balance, and gray and white cards are valid ways of determining proper white balance, shouldn't they all look the same?</p>

</blockquote>

<p>No, not really. This is just one reason why we shoot raw instead of letting the camera produce the conversions from raw to JPEG. We get to decide the rendering. And when shooting raw, you really don’t need a WB card at all in it has zero effect on the raw data. It may make it easier for you to get to your desired color appearance but it has nothing to do with the data itself. </p>

<p>This article may help you understand the idea of user rendering:<br>

http://wwwimages.adobe.com/www.adobe.com/products/photoshop/family/prophotographer/pdfs/pscs3_renderprint.pdf</p>

[janne_moren]

"But the big issue, to me, is that if the camera is doing its job of determining proper white balance, and gray and white cards are valid ways of determining proper white balance, shouldn't they all look the same?"

 

 

No. Here's the thing: We humans are not great at white balancing. Our vision system tries to correct for changes in overall luminance, but it does an imperfect job. So a technically correct white balance (as determined by gray cards) can look off when it doesn't match the expected color tone. Usually, daylight situations will work OK with WB cards - sunlight, shade, cloudy and so on. But the more extreme the situation the more off it will be.

 

So, for instance, nighttime incandescent light balanced with a WB card will look much too blue - our vision is unable to completely compensate for the very reddish light, so we expect such scenes to be very warm-toned. On the opposite end, we expect anything under water to be bluish.

 

A WB card is a great way to get in the ballpark (and for technical photography it is sufficient and correct), but then you do need to adjust for our expectations and visual failings as well. The camera WB settings basically tries do do this, with varying amount of success. The real problem is, we can't just replicate human vision either, since our expected color tone for a picture is influenced by the brightness and tone of the room and surroundings we're in when viewing the picture too. The same print may look perfect outside on a cloudy day and completely off indoors at night.

 

BTW: No, I don't find any of the reds in the second image oversaturated, using two different monitors.

[mark_sirota1]

<p>While everyone else was not wrong, the fundamental error you're making is that the white card is blown out -- it's clipped. You need to stop down these shots so that it renders as a light gray.</p>

[joe_c5]

<p>Enough of the white card is clipped that I would not recommend using it for white balance.</p>

<p>Of the three images you posted, only the second image has a gray card that is actually neutral gray, at approximately RGB 164 164 164.</p>

<p>So long as your gray card is actually neutral gray (which is difficult to verify) then only that second image, which was white balanced using the gray card, is correctly white balanced.</p>

<p>If the white card were not overexposed to the point of clipping, then it could probably be used to obtain a similar white balance to the gray card.</p>

<blockquote>

<p>3 - Regarding the 2nd photo, the one set with gray card: How does the red tail lights and flowers look to you? They look a bit over saturated with too much red to me. My shirt looks like it is glowing and while it is a bright orange shirt, it just doesn't look natural to me.</p>

</blockquote>

<p>The shirt looks fake, yes, but most if not all of that is the nonlinear tone curve being used by DPP. I tried using the gray card for white balance with a linear tone curve and it looks much more like a real shirt.</p>

<blockquote>

<p>4 - Yes, the first photo, camera's auto white balance, looks a bit cool to me also.<br /> But the big issue, to me, is that if the camera is doing its job of determining proper white balance, and gray and white cards are valid ways of determining proper white balance, shouldn't they all look the same?</p>

</blockquote>

<p>The white and gray cards are more valid methods than auto white balance. The auto white balance just has to guess without enough information. In particular, auto white balance knows neither the color the light nor the color of the gray and white cards.</p>

[Tim_Lookingbill]

<p>WB card work better in a studio setting with controlled, consistent lighting.</p>

<p>Outdoor lighting especially in mixed shade and direct sunlight presents too many variables for consistency shot to shot.</p>

<p>Your best bet is to get one image looking correct and save those settings and apply to the rest. I'ld slightly warm up the top image. I don't see the shirt that saturated. Overall colors look more balanced over the others. Shade from my experience isn't THAT blue, but it isn't green or orange either. It's really a matter of taste, though.</p>

<p>Suggest for better consistency in lighting like this shot to shot for later ease of correction of WB in post is to set your incamera WB to Daylight and forget it. AutoWB will cause the Raw preview in post to constantly change shot by shot according to whether it sees more blue from the shade or more warm from the sunlight where ever you point the camera. This causes more tweaking image by image in post with the <em>"save from one and apply settings to others"</em> approach.</p>

<p>Welcome to digital processing. You're dealing with what film labs have to deal with from the few that are still around.</p>

[hjoseph7]

<p>You probably would have gotten more accurate results if you used a Custom White balance under those lighting situations and using a grey card as your target import. </p>

[digitaldog]

<blockquote>

<p>You probably would have gotten more accurate results if you used a Custom White balance under those lighting situations and using a grey card as your target import.</p>

</blockquote>

<p>For raw capture, you really want white (non specular), gray is fine for JPEG. Its all about the data distribution in a raw versus a rendered image. Half of all the data is in the first stop of highlight capture. While you <em>can</em> use a darker tone, that can introduce more color bias. This is the reason we see white cards today (gray in the past, film was not a linear capture).</p>

[jacopo_brembati]

<blockquote>

<p>Here's the thing: We humans are not great at white balancing. Our vision system tries to correct for changes in overall luminance, but it does an imperfect job.</p>

</blockquote>

<p>Wrong point of view.<br>

White balance try to mimic human visual system chromatic adaptation.<br>

Human visual system chromatic adaptation is not <strong>imperfect </strong>. It is as is, wonderful I think.<br>

If you try to simulate <strong>human visual system white balance</strong> from camera shots you have to remeber that <strong>chromatic adaptation is incomplete (not imperfect)</strong>.<br>

That is the reason we see sunset/sunrise different from daylight.<br>

Using a gray card, you get a "daylight shot". That may be good or bad depending on situation.</p>