The best way to have a "perfect" WB is to shoot a neutral gray surface (like kodak gray cards) and to use the LR color picker to get your wb adjustement. I don't know how to do that underwater but I suppose you can take a photo of any waterproof gray card with your strobes at the begening of your dive session and then synchronize all you set with the color adjustement you have mesured on the first image.

For White Balancing, especially for raw data, a neutral white is better than gray. This target is very neutral and water proof!

http://www.babelcolor.com/main_level/White_Target.htm

Bummer. Best target out there. I emailed them to see what’s up.

Bill_Janes wrote:

 

The Babel white target has a nearly 100% Lambertian reflectivity, which makes it very useful for calibrating spectrophotometers and other instruments where 100% is desirable, but this is not necessarily good for white balancing photographs.

Did a superb job WB for me (cause it is so darn neutral). It was also awesome for ETTR testing.

You can use gray cards but for raw workflows, due to the Distribution of data, white is preferred and recommended (and hence the name of the operation). IF the gray card is spectrally neutral, it can work too but if off a bit, you can end up with some color shifts. But there are all kinds of tools out there that can work. I’ve heard of folks getting good results using coffee filters!

Bill_Janes wrote:

 

Actually, white is not preferred in most cases since it is very difficult to produce a spectrally neutral white.

Bill, really. You just want to start another argument?

Yes it is difficult to produce a spectrally neutral white. Danny did a superb job with his target. Shame it will no longer be offered, glad I have two. Yes, a spectrally neutral white, or gray is harder to produce than a non spectrally neutral white or gray. What’s your point about it not being preferable as I pointed out? That the white patch of the Color Checker is not neutral isn’t desirable is it? I’ve measured it and Danny’s target. One is super darn neutral. What is the argument on your part that this isn’t ideal? Hard to produce, yes, we agree.

If you’re saying, if you have two patches, one neutral and one not neutral but closer to white, use the more neutral patch, well I don’t think anyone would disagree. I’m saying a white that is neutral is preferable to a gray when both are neutral. And naturally a neutral white is vastly superior for the job than a gray that isn’t neutral.

Andrew Rodney wrote:

Bill, really. You just want to start another argument?

 

Yes it is difficult to produce a spectrally neutral white. Danny did a superb job with his target. Shame it will no longer be offered, glad I have two. Yes, a spectrally neutral white, or gray is harder to produce than a non spectrally neutral white or gray. What’s your point about it not being preferable as I pointed out? That the white patch of the Color Checker is not neutral isn’t desirable is it? I’ve measured it and Danny’s target. One is super darn neutral. What is the argument on your part that this isn’t ideal? Hard to produce, yes, we agree.

 

If you’re saying, if you have two patches, one neutral and one not neutral but closer to white, use the more neutral patch, well I don’t think anyone would disagree. I’m saying a white that is neutral is preferable to a gray when both are neutral. And naturally a neutral white is vastly superior for the job than a gray that isn’t neutral.

Andrew,

I am not trying to start another argument, but simply want to point out a limitation of the Babel target that you have not acknowledged. There are two ways to use a WB target. One is to take a custom WB in the camera by exposing the target so that it fills the frame of the camera and taking a shot to set the white balance. In this case, white is not necessary since more exposure of a spectrally neutral gray target will give the same results. Most Nikons automatically increase the exposure over mid gray to get a better reading. This method is not practical with the Babel target, since it is so small.

The other method is to include the target in the scene and then white balance with the eyedropper. If you are exposing to the right a scene that does not contain areas of 100% reflectance (and few do), you place the brightest area of the scene just short of clipping. A sheet of white paper and most naturally occurring whites have about 90% reflectance. If you place these "whites" just short of clipping, the Babel target will be clipped. In this case, it is better to use a WB target that has less reflectance than the brightest area of the scene. Light gray will avoid clipping and still give a low noise reading. The WhiBal is a good compromise and comes in sizes that enable the first WB method.

Andrew Rodney wrote:

 

Bill_Janes wrote:

I am not trying to start another argument, but simply want to point out a limitation of the Babel target that you have not acknowledged. There are two ways to use a WB target. One is to take a custom WB in the camera by exposing the target so that it fills the frame of the camera and taking a shot to set the white balance.

For the custom WB the camera uses for JPEG (that isn’t used for raw)? The Babel target would not be used for this, wasn’t designed for it and is (was) far too expensive for JPEG only users.

The other method is to include the target in the scene and then white balance with the eyedropper. If you are exposing to the right a scene that does not contain areas of 100% reflectance (and few do), you place the brightest area of the scene just short of clipping. A sheet of white paper and most naturally occurring whites have about 90% reflectance. If you place these "whites" just short of clipping, the Babel target will be clipped.

OK, this is the kind of WB I’m talking about. WB using the eyedropper IN the raw converter on a target that is spectrally neutral. I thought I made that clear, if not, sorry. And I’d suggest that the Bable target is a great product to use to avoid clipping (don’t clip it). It is just shy of what one would target as a specular you might want to clip.

 

WhiBal is an excellent product. It doesn’t measure out to the neutrality or reflectance of the Babel target but just because Babel has better spec’s (at a price) doesn’t mean WhiBal will not do the job. Had I known when I first posted about Babel that it was not available, well I would not have mentioned it and would have recommend WhiBal. But if price wasn’t an object, and someone asked “based on empirical testing, which target produces the best measurements” I’d have said Babel. The values Danny mentions on his site and what I measured with an EyeOne were extremely close.

The first method is the only one to use for in camera JPEGs, but it also works for raw. The preset is white balance is included in the metadata for the raw file. If it is not clipped, the Bable would be the best solution, but if one is ETTRing a black cat a darker target would likely be better.