Selecting by Color Ranges/Tone

The Select > Color Range command allows us to interactively create selections based on one or more color ranges or tone using a dialog box.  Selections are made using either a drop down box or eyedropper tools.  Once the selection is made, it can be used like any selection made by the marquee, lasso or magic wand tools.  The Color Ranges and Color Channels page provides a thorough understanding of color ranges.

A sample Color Range dialog box is shown in Figure 1.
 

Table 1.  Color Range Dialog Box Description

A	The dialog box window shows either the image or the selection.  It defaults to showing a selection.  Selections are shown as masks.  White areas are selected.  Black areas are not.
B	The drop down box allows the creation of a selection based on a predefined color range or three tone choices: highlights, mid tones or shadows.
C	The eyedroppers are used to create custom selections based on color ranges.  The eyedroppers, from left to right, are: create, add to and subtract from.  The left most eyedropper will create an active selection around whatever color range is clicked on in the document window.  If a selection is already active, it will deactivate it before creating the new selection. The + eyedropper will add the color range clicked on to the currently active selection. The - eyedropper will subtract the color range clicked on from the currently active selection. The drop down box must be set to Sampled Colors for the eyedroppers to be active. It is best to use the eyedroppers by clicking in the document window, not in the dialog box window.
D	The Invert check box allows the currently active selection to be inverted.  This is the same as clicking Select > Inverse.
E	The Fuzziness slider increases or decreases the active selection.  The adjustment is based on color range, not on proximity.  Moving the slider to the left reduces the selected area.  To the right, increases it.
F	The Selection/Image radio buttons allow the toggling between a preview of the selection or the image in the dialog box window.
G	The Selection Preview drop down box overlays the image in the document window with the selection mask.  This allows for the verification of the selection.  The preview options are: None - Do not display the mask in the document window. Grayscale - The overlay mask is the same as the mask in the dialog box. Black Matte - The selected areas are shown as normal.  Unselected areas are covered with black. White Matte - The selected areas are shown as normal.  Unselected areas are covered with white. Quick Mask - The selected areas are shown as normal.  Unselected areas are covered with the semitransparent rubylith color.

Example

In this example, we will use the Color Range command to create a selection around the blue sky in Figure 2.  We will then turn the selection into an Levels adjustment layer mask.

1. Click Select > Color Range to display the Color Range dialog box.
2. Using the left most eyedropper , click on the blue sky once.
3. Examine the selection mask in the dialog box window.  Determine if too much or too little color ranges have been selected.  If unsure, use the Selection/Image radio buttons or Selection Preview to toggle between image and mask.
4. If too much has been selected, decrease the Fuzziness value.  Or, use the - eyedropper and click in the document window those areas that should not be selected.  As areas in the document window are clicked, they will appear black in the mask. Be sure to use the - eyedropper and not the left most eyedropper.  Otherwise, a new selection will be created.
5. If too little has been selected, increase the Fuzziness value.  Or, use the + eyedropper and click in the document window those areas that should be selected.  As areas in the document window are clicked, they will appear white in the mask.  Be sure to use the + eyedropper and not the left most eyedropper.  Otherwise, a new selection will be created.
6. Once the selection is as desired (see Figure 3), click OK to close the Color Range dialog box.  The active selection will be seen in the document window.
7. Click Layer > New Adjustment Layer > Levels.  Or, click the Create New Fill or Adjustment Layer icon at the bottom of the Layers palette.  At this point, the adjustment layer will be added to the Layers palette with a layer mask that looks the same as the mask created with the Color Range dialog box, as seen in Figure 4.