Latest info on white balance meaurement tools

Drew Strickland has recently updated the Web site for his ColorRight/Color Right white balance diffuser. Those of you seeking to keep up-to-date on this product field may find it interesting:

http://www.colorright.com/pro-white-balance-review

I will make no comment on the page since I have made a commitment to my colleagues on the Pro Photo Home forum that I will no longer draw attention to inconsistencies in the content of ColorRight/Color Right promotional materials, and I will honor that here as well.

This is in the spirit of 1 Corinthians 13:13 (one of Drew's favorite scriptural citations, although he prefers a different translation than I):

And now abideth faith, hope, charity, these three; but the greatest of these is charity.

The truth - is it stranger than fiction?

In part as compensation for my earlier uncharitable challenges to some of the language in Drew's promotional material on the ColorRight/Color Right, I would like to illuminate an important passage in his latest material which I find to be wholly accurate.

It appears under the heading "Accurate"(!):

The Color Right has multiple carefully selected spectrally neutral layers. Some of these layers block light, while others help ensure a center-weighted measurement. Each layer has been carefully selected to ensure accurate white balance.

Let me vet each of its clauses. (I'll edit to separate out different aspects.)


The Color Right has multiple . . .layers.

Indeed. My Color Parrot 1.2 (which I suspect to be illustrative of the design of the ColorRight/Color Right), has four layers in its "stack":

A. Clear glass

B. Translucent disk (evidently some type of "foam" plastic)

C. Opaque disk of black paper or the like with a central round hole

D. Clear glass


[The layers are] spectrally neutral.

We think this may either mean "spectrally uniform" or "chromatically neutral", or perhaps both.

Layers A and D appear to be chromatically neutral. They are likely spectrally uniform as well.

Layer B (the actual "diffuser") appears to be very close to chromatically neutral in its transmission. It may well be nearly spectrally uniform (but I could not test for that).

As to layer C, I suppose "opaque" can be said to be "neutral" (it certainly has no saturation).


Some of these layers block light. . .

Well, layer C certainly does. (Its only effect on the behavior of the diffuser is that it limits the size of the luminous disk presented to the lens.)


. . . while others help ensure a center-weighted measurement.

We believe this is a reference to the relatively narrow "acceptance pattern" of the ColorRight/Color Right.

If so, this is in fact a result of the properties of layer B, which (like typical simple diffuse transmissive elements) inherently exhibits a relatively narrow acceptance pattern.

This property is not affected (to any significant degree) by layer C.


Each layer has been carefully selected to ensure accurate white balance.

Certainly layers A, B, and D have evidently been chosen to lead to an overall chromatically neutral transmission.


Best regards,

Doug