Thanks Paul. I'm an engineer by education and therefore constrained to ask "how did one come up with this?" Ron's eBook "sort of" states "because I said so..I've processed hundfreds of thousands of images." This is not to deprecaite him or his work in any way. I"m sure his experience bears this out....otherwise I wouldn't adhere to his technique....or spend quite a bit of my own money to atend his class this fall. I would simply like to have a better understanding of what I'm doing here.
I don't use curves either; never seemed necessary using NC and RR's techniques.
I can't wait till early October to spend three days dedicated to pure photography and post processing.
I know its a bit OT but since moving from film to digital i have had for more questions than answers! Paul thanks for clearing up one of those questions about moving the sliders becuase i never could understand why i was doing it!
I remember asking Ron this at the workshop I took a couple of years. Memory is a touch fuzzy, but as I recall the short answer is "because it works" :lol: .
And I believe that the longer answer had to do with Ron's background and understanding of video and color in general. Paul's commentary sounds quite familiar as well, so I think it is at least close. This would be a good topic for an email to Ron.....
I haven't taken the time to correlate the times of the postings both here and on DPR, but there's some credible discussion there as well (for a change).
Perhaps the short answer is that using this process attempts to neutralize the shadow areas which tend to be biased in many shots. When you look at a photo, these areas are more noticeable than when your brain does its thing and mitigates the light color when you are actually there.
I like to think of it as manually adjusting a photo's WB to correct for things in the same way that your brain does when you are standing there in front of the scene.
I recently read Rons ebook and found it worth while. From my point of view it is more like micro white balance. Much like applying USM to only the eyes in a portrait.
You capture an image in direct sun and WB is set to daylight. The midtones and highlights will have the correct WB. Shadows are created by being in the shade of something else. The WB of the shadows is actually shade. That may not look right so you neutralize it to daylight. Clear as mud?
I could be wrong in which case I am ready for my flogging from the RR students.
Guys, the WB adjustment itself does have an effect on the shadows, but it has more effect on upper shadows through the highlights. As has been stated, the deeper shadows are often affected by the color reflected into those shadows, and they can have a significant color cast all their own. By balancing the shadow levels to the same physical point on the curve (not the same numerical value), you can partially or completely offset a color cast while pre-biasing the channels to assist in contrast adjustments. Sometimes this is all the contrast adjustment that needs to be made. In other cases, you either want to pre-bias the shadows using the LCH Lightness channel to move the black point up in all channels together, then bias the individual channels, or do a global RGB composite channel adjustment after the individual channels have been adjusted, or both.
Clear as mud, right?
Simple answer? It works. It's fast, easy and repeatable.