)
in the Channels Palette.
MIT 4.202
Geometric Modeling Fall 2003
Lab #2 Handout
Selections, Layers and Channels
4.202 students should always
look on the web for their exercise requirements and deadlines.
http://cat2.mit.edu/4.202/
Class locker on soap.mit.edu
Z:\soap.mit.edu\arch\class\4.203
Samples Files
Z:\soap.mit.edu\arch\class\4.203\Exerecise1-DemoFiles
| Marquee Palette | |
| Lasso Palette | |
| Feather Option | Blurs edges by building a transition boundary between the selection and its surrounding pixels. This blurring can cause some loss of detail at the edge of the selection. The number represents the feather radius in pixels. |
| Anti-alias Option | Smooths the jagged edges of a selection by softening the color transition between edge pixels and background pixels. Since only the edge pixels change, no detail is lost. Anti-aliasing is useful when cutting, copying, and pasting selections to create composite images. You usually want this option checked to get a smooth edge. |
| Magic Wand |
The magic wand tool lets you select a consistently colored area (for example, a red flower) without having to trace its outline. You specify the color range, or tolerance, for the magic wand tool's selection. |
| Shift | Adds the new selection to the current selection |
| Alt | Subtracts the new selection from the current selection |
| Select > Color Range... | The Color Range command selects a specified color or color subset within an existing selection or an entire image. If you want to replace a selection, be sure to deselect everything before applying this command. Use the droppers to select the color you want to pick out. Change the fuzziness factor to select a wider or narrower range of colors. |
| Select > Save Selection... | Saves the selection
as an channel. Another means of saving a selection is by clicking on the
Save selection as channel icon ()
in the Channels Palette. |
| Select > Load Selection... | Loads a saved selection. A selection / channel is a 8 bit image where white represents a selected pixel and black represents a non-selected pixel. The greys in between represents a percentage of how much the pixel is selected. |
| Quick Mask
Mode |
Allows you to quickly visualize selections especially if they are feathered. |
Clone
Stamp Tool |
The clone stamp tool takes a sample of an image, which you can then apply over another image or part of the same image. Each stroke of the tool paints on more of the sample. Use the Alt key to specify where to clone from. With the alignment option off, the clone tool will always sample from this area. This tool is commonly used to cover up portions of an image. Often times, you will want to clone onto another layer so you can preserve the original. In order to do that, you will need to check Use All Layers and make sure your current layer is the new layer. |
Gradient Tool |
Creates a gradient between 2 or more colors.You fill an area with a gradient by dragging in the image. The starting point (where the mouse is pressed) and ending point (where the mouse is released) affect the gradient appearance, depending on the gradient tool used. |
Layer Style |
Blending Options, Drop Shadow, Inner Shadow, etc... |
|
Layer Mask |
Adds a mask to a specific layer |
Layer Set |
Adds a layer set which allows you to group a collection of layers into one folder. |
Layer Adjustment |
Levels, Curves, Hue Saturation, Invert, etc... |
New Layer |
Creates a new layer. |
Delete Layer |
Deletes a layer. |
| Ctrl-G | Groups two layers together. Typically used to make a layer style or layer adjustment affect only one layer. |
| Ctrl-Shift-G | Ungroups two layers. |
| Does not depend on other layers | Normal, Dissolve, Behind, Clear |
| Darkens the underlying image | Darken, Multiply, Color Burn ,Linear Burn |
| Lightens the underlying image | Lighten, Screen, Color Dodge, Linear Dodge |
| Adds contrast to the underlying image | Overlay, Soft Light, Hard Light, Vivid Light, Linear Light, Pin Light |
| Compares the active layer to the underlying image | Difference, Exclusion |
| Applies certain qualities of the active layer to the underlying image | Hue, Saturation, Color, Luminosity |
HL 2003.09.11
