Eyedropper Sample Points

The Curvemeister 3 Reference

Eyedropper Samples

Figure 1. There are six Eyedropper Samples shown on the image on the right. Can you find them all?

The three small colored windows are sample panes showing color values. These are indicators only that do not modify the curves, or change any color values.

The sample marked with an n on the left is a neutral point. The two located near one another on the butterfly's body are a highlight and shadow.

Highlight, shadow, and neutral sample points are called constrained samples. The effect of a constrained sample is not localized to a particular area of the image, but affects the color globally.

Using Eyedropper Sample Points

You may create an eyedropper sample by right-clicking on the image window, and selecting the New Sample Point command , or by alt-clicking an image point.

Eyedropper samples are an important addition to your ability to quickly observe, and also manipulate the colors of your image. If a sample is configured to change colors, it is known as a pinned sample. Pinned samples operate using curves. Conceptually, it is important to realize that sample points modify the curves to alter colors. They therefore change colors uniformly throughout the image, not just under the sample point itself.

Eyedropper samples that are not pinned are display only. They allow you to compare numeric results for by the numbers color correction. They come in several variations, determined either by the way the eyedropper is created, or modified using the eyedropper menu.

Shadow and highlight points have already been discussed in the wizard documentation. Next to curves themselves, they are probably the most important tool in Curvemeister's color correction repertoire because they allow you to instantly set the areas of important black and white detail, simultaneously increasing image contrast range, and eliminating color casts. Before Curvemeister, each of these operations required three separate operations on three curves.

Neutral points further leverage your ability to quickly get rid of color casts. If a color cast remains after setting the shadow and highlight, or if your image lacks a good shadow or highlight, you may eliminate it using a third type of eyedropper sample, the neutral point.

Initially, you will want to focus on becoming fluent with shadow, highlight, and neutral. Advanced eyedropper features are accessed using the Eyedropper Menu, discussed below.

The Eyedropper Sample Menu

Figure 2.

Click on the eyedropper menu button, located in the upper right corner of the eyedropper info window or "palette" to display and manipulate color values.

Display

Figure 3. The Display submenu specifies the color model that will
be used to the display the color values for the particular sample.

Actual Color - specifies that the eyedropper display its color values in the current working color space. The color space values will change depending on the current setting of the mode buttons located along the middle right edge of the Curve Window. This is the default.

wgCMYK - specifies that color information be displayed in Wide Gamut CMYK.

RGB - displays color information in Wide Gamut CMYK.

Lab - displays color information in Lab.

HSB - displays color information in HSB.

Other Supports display of color information in a variety of other formats.

Sample Size

Figure 4. The Sample Size sub-menu specifies the dimensions of the square area that is averaged to determine the sample value.

Point - calculates the sample color using a single pixel from Photoshop's native image.

3x3 - calculates the sample color using 3x3 array of pixels, centered on the sample point. A larger sample size is less likely to be affected by the noise that is ever present in a photograph.

5x5 - calculates the sample color using 5x5 array of pixels, centered on the sample point..

11x11 - calculates the sample color using 11x11 array of pixels, centered on the sample point..

Arbitrary - this menu item is always disabled in version 1.1.2.

Hue Clock - specifies a variety of combinations for displaying the numeric color values and the Hue Clock associated with the sample value.

Figure 5. The Pin Color submenu of the Eyedropper Sample Menu
specifies several choices for the pin Color.

Pin Color - controls the desired color of the pinned constraint, called the pin color or target color. This color may be thought of as the goal of the pin, with the Pin Mode determining how that goal is achieved.

Color Picker ... - invokes Photoshop's color picker dialog. This allows you to choose a color in a variety of ways, including numerically in several color spaces, visually, or by choosing a predefined color from Photoshop's library of Pantone and other color inks.

Original Color from Image - sets the pin color to the original, uncurved sample color. Use this option to lock hold a color from the original image in place, as you use curves or pins to make adjustments to other colors.

Curved Color from Image - sets the pin color to the curved sample color. Use this option to lock in a modified color so that it will stay put while you perform other pinning or curve operations.

Photoshop's Foreground Color - sets the pin color to Photoshop's foreground color. This allows you to pin to Photoshop's foreground color, in essence treating that color as a pin. This is used when you wish to quickly perform a pinning operation, but do not wish to create a pin.

Photoshop's Background Color - sets the pin color to Photoshop's background color. The same as the previous command, except that it uses Photoshop's background color.

Pin Mode - this submenu specifies how the image color will be converted to the pin color.

Figure 6. The Pin Mode determines how curves will be used to
change the original color of the sample to the pin color.

Shadow - specifies that the pinned sample will create curve points tomodify the dark endpoints of the curves to achieve the Shadow value specified in the Curve Options. This supports only one shadow value, however you may create any number of shadow values using the Pin Palette's New Pin command..

Highlight - similar to the Shadow command, but specifying pinning to a highlight value.

Neutral - specifies that the pinned sample will create curve points to remove color from the sample. The pin color is ignored for this operation.

Hue/Sat - specifies curve points will be created such that the color hue, and intensity of the pin color will be recreated. This pin mode allows an object of constant color to retain a natural variation in brightness values, and it is probably therefore the most useful mode of all. This command is the same as selecting Hue and Brightness.

Hue/Sat/Bri - specifies that curve points will be created so as to exactly match the pin color in every way. This is useful for changing logo colors, or other colors that must have as exact a match as possible. It is also used for calibration operations. This command is a shortcut for selecting Hue, Saturation, and Brightness.

Hue - specifies that the curves should be changed to achieve the color of the pin color, but not the intesity or overall brightness. This is a relatively unusual combination by itself, however it does a good job of preserving the rounded appearance of objects with saturated color, such as fruit. This option may be combined with the Saturation and Brightness options.

Saturation - specifies that the amount of white mixed with the color should be preserved. This option is almost never used by itself.

Brightness - specifies that the curves should be modified to achieve the brightness, but not the color, of the pin color.

None - specifies that no curve changes of any kind should be made. Tthe sample point still retains its pin value, so this mode may be used to compare the source and pin colors numerically, without modifying the colors. This is very useful for calibration operations, where deltaE values should be displayed. See also the Save Samples menu commands in the Image Preview menu.

Disable Pin - when checked, this menu item temporarily changes a pinned sample to a read only sample. This is used to assess the effect of a particular pin, and to retain the pin after the Curve Window's Reset button has been clicked.

Save Sample as Pin ... - creates a new pin, located in the current tab of the Pin Palette, whose pin color and mode are copied from the pinned sample. You will be presented with the Pin Edit dialog, and you may name the pin and make any desired changes before saving the pin.

Mark - adds a small triangular marker to the curve points corresponding to the eyedropper sample color. This is a significant bookkeeping aid, and is useful for determining color overlaps between important objects in your image, and for steepening or otherwise modifying particular ranges of color.

Delete Sample Point (shortcut key delete) - deletes any currently selected eyedropper samples, including shadow, highlight, and neutral points. To delete all the eyedropper samples, type control-A followed by delete. Note: you may also find it useful to use the Curve Window Reset button, which will delete pinned samples, and retain any unpinned samples.

Copy Color - Copies the sample color to the clipboard as text.