Doug Kerr
Well-known member
I just received the following from the manufacturer of the ColorRight white balance measurement tool (it is, verbatim, in blue). I have taken the liberty of embedding some comments.
My recent comparative test of 10 different white balance devices (results to be published soon) put the Colorright [sic] disk at the top of the pack . ...the Expodisc [sic] was one of the somewhat less successful devices tested.
This will of course be fascinating reading. I'll be particularly interested to learn of the technique used with the ExpoDisc in the test series.
The physics of light and response to light by contemporary camera sensors is such that, particularly with the correction of excessively yellow capture, you actually cannot fix everything in post.
Hopefully, the author is speaking of postprocessing of JPEG image files.
It is not at all clear that "The physics of light and response to light by contemporary camera sensors" explains why correction for the chromaticity of the incident light cannot be successfully done to an already-demosaiced image. In fact, the images captured by our sensors can be successfully corrected (as happens, for example, with the use of Custom White Balance, or in color correction during the development of raw image files.).
It is largely the demosaicing process (not a property of the sensor, unless we mean that the need for it comes from the use of a color filter array sensor) that thwarts our ability to successfully apply WB color correction to a JPEG image.
Use of Auto WB+ “fix it later” is a gross misunderstanding of capture.
Well, I'm not sure we often see it suggested that WB correction be attempted on JPEG files.
Most regrettably, this procedure automatically lessens your control, your commercial grade accuracy and your artistic possibilities - and definitely boosts perversion of files in terms of color cross-over and both luminance and chrominance noise.
Consistent use of custom WB will boost the quality of your capture at least 100%."
Wow! 100% I wonder what scale that is on.
Thoughts regarding ColorRight and her soon to be published review. (Master Photographer and Teacher, Sara Frances )
**********
Sara Frances, M.Photog.Cr., writes the Column "The Boutique Photographer" for Professional Photographer, an online magazine.
In her 2007 article, "White Balance, the Secret Weapon", Frances tells us:
"Raw files, though far more robust and editable than JPEG, are not fully color correctable without consequences."
Here is a link to the article proper, which gives some interesting hints about performing WB color correction in Photoshop:
http://www.ppmag.com/web-exclusives/2007/11/white-balance-the-secret-weapo-1.html
My recent comparative test of 10 different white balance devices (results to be published soon) put the Colorright [sic] disk at the top of the pack . ...the Expodisc [sic] was one of the somewhat less successful devices tested.
This will of course be fascinating reading. I'll be particularly interested to learn of the technique used with the ExpoDisc in the test series.
The physics of light and response to light by contemporary camera sensors is such that, particularly with the correction of excessively yellow capture, you actually cannot fix everything in post.
Hopefully, the author is speaking of postprocessing of JPEG image files.
It is not at all clear that "The physics of light and response to light by contemporary camera sensors" explains why correction for the chromaticity of the incident light cannot be successfully done to an already-demosaiced image. In fact, the images captured by our sensors can be successfully corrected (as happens, for example, with the use of Custom White Balance, or in color correction during the development of raw image files.).
It is largely the demosaicing process (not a property of the sensor, unless we mean that the need for it comes from the use of a color filter array sensor) that thwarts our ability to successfully apply WB color correction to a JPEG image.
Use of Auto WB+ “fix it later” is a gross misunderstanding of capture.
Well, I'm not sure we often see it suggested that WB correction be attempted on JPEG files.
Most regrettably, this procedure automatically lessens your control, your commercial grade accuracy and your artistic possibilities - and definitely boosts perversion of files in terms of color cross-over and both luminance and chrominance noise.
Consistent use of custom WB will boost the quality of your capture at least 100%."
Wow! 100% I wonder what scale that is on.
Thoughts regarding ColorRight and her soon to be published review. (Master Photographer and Teacher, Sara Frances )
**********
Sara Frances, M.Photog.Cr., writes the Column "The Boutique Photographer" for Professional Photographer, an online magazine.
In her 2007 article, "White Balance, the Secret Weapon", Frances tells us:
"Raw files, though far more robust and editable than JPEG, are not fully color correctable without consequences."
Here is a link to the article proper, which gives some interesting hints about performing WB color correction in Photoshop:
http://www.ppmag.com/web-exclusives/2007/11/white-balance-the-secret-weapo-1.html
