Jun 25, 2009

Rave - Strong, Intuitive Tone Mapping Tools in CS4

New tools in Lightroom 2 and Photoshop CS4 are real time savers.  I'm thinking about Tone Mapping with Clipping Points, Targeted Adjustment Tools, and the Adjustments Panel.

CS4, Curves, Clipping Points, Photoshop, Lightroom

CS4 Adjustments Curves Clipping Point
This image shows red channel clipping.  After checking Show Clipping, by moving White Point slider to the left, I deliberately over clipped the area.
When real clipping was set to 235, underlying red and orange arch colors were more dramatic.  217 blew out some of the red channel.

What is Tone Mapping?
It’s how to look at an image and "listen" to it; how changes to the delicate matrix of light and shadow can transform drama and mood in the meaning of an image; how to sculpt perspective with light and contrast; and how to imagine gorgeous color and tonal changes to best express your vision.
Tone refers to the level of brightness.  Common terms describing tonal values are shadow, mid tone, and highlight brightness categories.
Contrast - simply put, contrast is difference between tonal values.  The greater the difference in brightness between tonal regions, the more contrast.
Clipping – tonal values recorded as either total black or total white.
So, let’s create a simple workflow which listens to our need for speed and accuracy as we Tone Map images?

Clipping Points
Our first step is to use Clipping Points of Curves dialog to set neutral Highlights and Shadows.  In CS4, click Adjustments panel, open Curves dialog, then click on the Expanded View list (upper right).  Check the 5th item Show Clipping for Black/White Points.  I know; it was a little easier to find in CS3 - you simply checked a Show Clipping box.
The horizontal histogram scale has two triangular points; on the left, the Black point, on the right, the White point.  When you move either point towards the middle, your image visually changes to begin showing when global clipping occurs.  This clipping image may have up to six colors, primary RGB or secondary CYM. 
You just decide when clipping starts and how much, if any, you want as you neutralize shadows and highlights.

CS4, TAT, Targeted Adjustment Tool, Curves, HSL, Black and White

Targeted Adjustment Tool
But, we're not done quite yet… let's move to the talented, localized Targeted Adjustment Tool!
First, we must warn you; this tool doesn't work as a single feature.  Rather, it works on Curves, Hue, Saturation, Lightness, and Black-and-White Adjustments.  Because it is selective, it only changes these effects for colors under the cursor.  WOW... that's more than a triple threat!
The icon for the TAT tool is a hand with forefinger pointing upward.  Next to the forefinger is a double headed arrow; it suggests you move the cursor up-and-down to independently modify contrast (Curves).  For color, intensity, and brightness, the double headed arrow is horizontal; move the cursor right-or-left (Hue, Saturation, Lightness, and Black-and-White). 
As you move the cursor, contrast or color may change - becoming stronger or weaker.  In HSL and B/W situations, one or more of the color sliders may react to your cursor motion.  This indicates more than one color is involved under the cursor.

Most of this discussion deals with CS4; the Lightroom 2 TAT tool icon performs the same functions.

Rant - Textbooks with Poor Indexing Using Different Terminology
While Clipping Point and TAT aren't gorgeous glamour tools, their early workflow usage is quite important.  Both tools are sort of buried in several functions of the Adjustments panel.
When asked about upgrading Photoshop, one of my tenant's is, "Get the best text to explain the complexity of your brave New World."  By best, I mean a text which clearly and explicitly explains where and how Adobe has adapted each of the new features.  I do not mean a users manual.
I have a Photoshop library of detailed works from Fraser (CS3), Kelby (LR2), Eismann  (CS3), and Evening (CS4).  Unfortunately, a methodical, by item approach to reporting Photoshop doesn't naturally group powerful tools with a similar, yet pervasive function. 
Some books contained a full index; Evening clearly didn't think to carefully guide you with a complete, in-depth index.  Some books treated these tools in more depth than others.  Some writers used English with both greater clarity and higher precision...
The result can be a lot of time-consuming digging.

For advanced Photoshop users who seek more than a ‘cook book’ approach to learning new and unique workflow, I suggest, if possible, you preview potential library entries prior to buying.  Make sure your new addition meets all your criteria for a new, exciting learning path.

Meanwhile, why not take a look at Clipping Points and TAT tools to smoothly speed your workflow!

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