Grey Card, White Balance help

Hey all, I've got a question.
I just started using a grey card, the colorchecker passport, to help me get my white balance at events, including my daughter's indoor volleyball courts. I shoot the card, and then use that image in lightroom to select white balance and apply that to the other photos takein in the same local area. Sometimes when they switch sides, window light comes into play, so I take another grey card exposure.

Anyways, I shoot RAW. And there are times I underexpose up to a stop in order to get a high enough shutter speed for the action.
My questions are...

Should I underexpose the grey card on that shot by one stop, as the pictures will be, or should I properly expose the grey card?

What white balance should I use when shooting the grey card? Does it matter?

I'm colorblind in some colors, and this colorchecker passport has made a BIG difference in my images, but for some reason I'm at a loss on these issues.

Thanks, Mike

WB card tonality, as supplied or as shot, does not matter. What matters is simply neutrality of R-G-B values. A lighter gray or an 18% gray does not matter. Using extremes like black or white means that clipping of one color channel like Red might throw off the WB tool. The problem of using ordinary copier or printer paper are the optical brighteners which are often used during manufacture, throwing the WB off (typically too strong in the Blue direction)

Tip: Overexpose the grey card a bit, like +1 stop, but not enough to clip it. The reason is that the LR probe measures a 5x5 pixels area. If a couple of those 25 pixels are Chroma noise that will throw off your WB calculation. More exposure reduces noise. If you really want to go whole-hog, you can even pull your ISO down to 100 for that shot - it doesn't matter if it's blurry slow.

If you are shooting RAW, it doesn't matter.

tzalman wrote in post #9827052
Tip: Overexpose the grey card a bit, like +1 stop, but not enough to clip it. The reason is that the LR probe measures a 5x5 pixels area. If a couple of those 25 pixels are Chroma noise that will throw off your WB calculation. More exposure reduces noise. If you really want to go whole-hog, you can even pull your ISO down to 100 for that shot - it doesn't matter if it's blurry slow.


If you are shooting RAW, it doesn't matter.

Outstanding info....thanks!
So focus/blur doesn't matter as much.

And...even if the grey card looks yellow/green, it's OK.

Sure, the balancing will make it grey. Besides, that yellow-green is only in the jpg preview, not the RAW.

I have been using the passport lately and making profiles.
Love it. I used it today for outdoor shots in diffuse light. I have better color than I ever achieved in the past.

I just searched for "colorchecker passport" as I just ordered mine a few moments ago. It'll be here tomorrow and I am very excited for that! I can use it everywhere as it is so portable and convenient to carry by the looks of it. Having accurate color 100% of the time, and with ease is priceless.

SoaringUSAEagle wrote in post #9870560
I just searched for "colorchecker passport" as I just ordered mine a few moments ago. It'll be here tomorrow and I am very excited for that! I can use it everywhere as it is so portable and convenient to carry by the looks of it. Having accurate color 100% of the time, and with ease is priceless.

I just used mine to shoot snakes at "snake road". This time of year, there are lots of muted colors. Perfect "is that the right color?" material. Images came out very well! Watch the video that xrite has online. It will answer some questions. Another nice thing is having continuity of color, particularly skin tones, no matter what environment you are in.

Gray Card…White Paper. What’s best?

After using this for three days, I already feel that my money has been made up. I've used it at my full time job to calibrate both nikon and canon cameras in the studio. I have yet to go out and get settings in different lighting situations but that is next on my list - daylight, shade, tungsten, fluorescent, etc...

Frank - I just read your thread - and I am glad to see that a white piece of paper works for you.