Grey Card and White Balance

[TheBigE]

I have just completed most of the PP for my latest batch of photos. I was wondering, if I could use a Grey Card for White Balance.

So for example, just snap a quick photo of the Grey Card in the same light before I take a photo. I would then just use the Picture of the Grey Card to get the correct WB settings for all photos in the same (or nearly same light)

Most of the time on my last batch of photos I went in on each photo and found what I thought should be "Grey" and used that as my WB reference point. This was not always possible in all photos and so I was thinking of trying to find a bit better way to really work with the correct WB.

It would be nice to have one photo with the WB and then sync that across the photos, and then tweak as needed on each photo.

Any thoughts are appreciated or let me know if I am missing the point.

[NorthernFocus]

That is a valid practice assuming the card is lit by the same light as the subject. Keep in mind that if you do as described, you will truly correct colors of things as if lit by true white light. So if you're shooting in a situation such as "golden hour" outdoor lighting, you will undo much of the effect of the natural light. The golden tones of light will be "corrected" to white.

[DanK]

yes to your question, and +1 what Dan wrote.

Except for situations like the ones Dan mentions, a neutral card is extremely useful, particularly if you shoot raw. You may want to adjust to taste after correcting, but you will start from a 'correct' WB.

Be careful in choosing a card. Some are designed for exposure, while others are designed to be spectrally neutral. The latter is what you need. I use a small whiBal. It's small enough to fit in my pocket and has a lanyard as well.

[Mike Buckley]

Keep in mind that there are two types of grey cards. As an example, a Kodak grey card (does Kodak still make them?) is used for determining exposure and is toned to match what the camera "thinks" is neutral grey. As a different example, the WhiBal card is used for determining neutral white balance and is made to be spectrally neutral.

[Donald]

Any thoughts are appreciated or let me know if I am missing the point.

You are bang on the money. Some of us would suggest that you start every session with a shot of a card. I, too, use a WhiBal ... and I do almost exclusively B & W.

Why use a WhiBal if you're shooting a photo to be a B & W image? Because that ensures that I have the RAW file 'correct' before I start the B & W conversion.

[xpatUSA]

Why use a WhiBal if you're shooting a photo to be a B & W image? Because that ensures that I have the RAW file 'correct' before I start the B & W conversion.

Interesting, Donald,

I thought that RAW data is unaffected by the white balance setting. Or have I misunderstood?

On my SD14 camera, any selected white balance setting, including Custom, is passed to the RAW converter as a full 3x3 matrix (9 coefficients) - therefore the converter can change to any white balance you might re-select after the fact. By which I do not mean color-picking a neutral which only uses a 'diagonal' matrix (3 coefficients).

Pardon the tech. talk:

A 3x3 matrix works the same as a 3-channel color mixer as found in RawTherapee and probably PhotoShop.

A diagonal matrix is the same as saying multiplying R, G, B by only one number each, not 3, i.e. for a pixel of color r,g,b it's new color becomes ar, bg, cb where a, b, c are coefficients calculated by the color-picker.

[Mike Buckley]

I though the RAW data is unaffected by the white balance setting. Or have I misunderstood?

The RAW data includes the data pertaining to the WhiBal card included in the scene. That portion of the image can then be used to easily change the white balance if needed as the first post-processing step after the software has converted the RAW data to image data. It works like a charm.

You could accomplish the same change by manually altering the white balance but using the card as the spectrally neutral source makes the change both reliable and quick. Much post-processing software has a capability of dropping an "eye dropper" on the WhiBal card in the image to automatically render a neutral white balance.

[chauncey]

a Grey Card for White Balance.

In times past, I was a fanatic about using it and still do when shooting people, esp. mixed races.
These days though, I consider it only as a guideline...giving the artistic value more liberties to roam.

[Manfred M]

I thought that RAW data is unaffected by the white balance setting. Or have I misunderstood?

Absolutely correct, but some editing programs import the embedded jpeg white balance data as a starting point (ACR / Photoshop / Lightroom do this for sure), so it just speeds up the workflow.

[Manfred M]

I have several targets, a xRite Color Checker passport (I tend to use this "in the studio), a WhiBal card for field work and a Lastolite target for video work. In a pinch, I will use a white shirt or a piece of white paper (sometimes a printed page with black ink). They all seem to work.

I know people will come back and tell me that I can't guarantee that these generic targets might not be neutral, and in theory they are correct. In practice, I've either been lucky or the materials I've chosen are close enough that they worked for me.

[xpatUSA]

The RAW data includes the data pertaining to the WhiBal card included in the scene.

Thanks Mike,

I should have it clearer. I meant that the raw file's image raw data is not affected by the camera WB setting.

[DanK]

Erik,

I forgot to respond to your question about syncing.

If you use Lightroom as your raw processor, this is trivially easy. You shoot one image first with the whiBal, in the appropriate lighting. Then, in LR, you select that image and use the eyedropper on the whiBal to set white balance. It is helpful to have other things, like a person in particular, in the rest of the image so that you can see whether you want to adjust this neutral white balance. Then click on the next image in the filmstrip on the bottom, hold the ctrl key, and click on the last image that you want to adjust. Choose settings, sync settings, make sure that only white balance is checked, and hit OK. Voila. All of your selected images now have the adjusted WB. Of course, you can tune them individually if you want, as you edit them.

Once you have done this once or twice, it is very simple and fast.

Dan

[russellsnr]

Hi, Use X-Rite colourchecker passport as it does everything from getting you the correct W/B and correct colour, if you don't want to spend a lot then the EZY-Balance Grey Card/Disc is another option just for W/B though.
Russ

[Downrigger]

These days though, I consider it only as a guideline...giving the artistic value more liberties to roam.

Me too.

Good thread, lots of helpful comments. I have started using Color Checker Passport for color profiles and WB as well. Two comments:

First the Color Checker Passport WB acknowledges the difference between "correct" and "best" by offering more than one pane as a reference (for your eyedropper). The instrument offers some warmer and cooler options both for skin tones and scenes, not only the strictly neutral/correct choice.

Second - even when using the color profile, and the neutral/correct or other choice for white balance color temperature, I very often tweak white balance/color temperature further and as I proceed with PP and differently for different shots in the same light. The same for the occasional tweak of hues in HSL.

For me, "Correct" is a good place to start and a comforting reference point, but not necessarily the finishing point in the process of rendering your preferred final statement. That said, I mostly shoot nature and landscapes and for the studio it may be that less deviation from "correct" gives the best result.

[Mike Buckley]

for the studio it may be that less deviation from "correct" gives the best result.

The only time that "correct" is absolutely mandatory is when we photograph a subject for the purpose of displaying it accurately. Forensic photography and product photography done for the purpose of encouraging potential customers to acquire the product are two examples. There may be others.

[rpcrowe]

I agree with Mike Buckley but, would add... Correct white balance is also quite important when skin tones are in the image. I tend to be sensitive to off color faces, especially if they tend towards the blue or green side... I can more easily live with reddish skin tones...

However, when I want to make sure that my color balance is accurate, I use my WhiBal card. It is so easy to balance out a series of shots in ACR by selecting all the shots and using the white balance eye dropper... I definitely also do this with my portraits of colored dogs. When I do portraits of white dogs, I use the white balance eye dropper on the white coat of the dog.

[DanK]

Second - even when using the color profile, and the neutral/correct or other choice for white balance color temperature, I very often tweak white balance/color temperature further and as I proceed with PP and differently for different shots in the same light. The same for the occasional tweak of hues in HSL.

For me, "Correct" is a good place to start and a comforting reference point, but not necessarily the finishing point in the process of rendering your preferred final statement. That said, I mostly shoot nature and landscapes and for the studio it may be that less deviation from "correct" gives the best result.

I completely agree. I often find myself slightly warming images from a neutral starting point. However, I find that starting from neutral is very helpful. I think it is very difficult to eyeball WB in a complex image, and when I haven't started from a neutral point, I have sometimes decided later that I really missed the boat and have had to go back and re-edit.

[Mike Buckley]

I agree with Mike Buckley but, would add... Correct white balance is also quite important when skin tones are in the image.

Agreed. However, it is possible to use an "inaccurate" white balance for most of the image so long as the skin tones are selectively adjusted to be more realistic.

[rpcrowe]

Here is an example of creative (rather than dead-on accurate) color balance in these two shots...

[TheBigE]

Thanks everyone, a ton of good information here and really helpful. Looking to find a WhiBal and Grey Exposure card in Germany.

I have seen some cards with a color palette as well, is that worth investing in at this point? I am not really sure the additional value this would add for me at this time.

I also agree, that the WB does not always produce the most desirable image. Here is an example of where I think the defalut WB was good and gave it a much warmer feel. I like to get it close and then tweak as needed.