tailieunhanh - Photoshop CS3 for Screen Printers- P15

Photoshop CS3 for Screen Printers- P15: The toolbox is the heart of Photoshop CS3, and where you’ll find the tools you need to create your artwork and perform editing tasks. From the toolbox you can access the selection tools, shape tools, type tools, Crop tool, and eraser tools. These are basic tools that any screen printer or graphic artist needs. | 396 Part IV More Tools 2. Choose Layer Add Layer Mask Reveal All to reveal the entire layer or Layer Add Layer Mask Hide All to hide the entire layer. To create a layer mask that hides or reveals a selection only 1. Select the layer to which you want to add the mask in the Layers palette. 2. Make the selection for the mask using a selection tool. 3. Choose Layer Add Layer Mask and either Reveal Selection or Hide Selection. Only the selection will be hidden or shown and this selection can be edited independently of the other parts of the image. To work with layer masks that have been created 1. Select the layer in the Layers palette that contains the mask you wish to edit. Click once on the layer mask thumbnail to make it active. 2. Select an editing or painting tool. 3. Paint with white to subtract from the image black to add to it and gray to partially hide the layer. You can switch to using the foreground and background colors in the toolbox and revert to the original black and white there too. 4. When complete you can either apply or discard the mask by holding down the Shift key and clicking once on the mask in the Layers palette. A red X indicates that the mask is discarded. Using layer masks allows you to separate and control specific parts of an image by producing a stencil of a selection. This stencil can be altered but the area around it is protected from change. These selections can then be saved for later use by saving the mask in an alpha channel. This is briefly detailed next. A Little about Alpha Channels You can save a selection as an alpha channel mask. Saving the selection as a mask will allow you to keep your work for later use. Alpha channels are storage areas for data like selections. When a selection is saved as a mask this channel is created automatically. 397 Chapter 21 Pens Paths and Masks You can also save a selection manually. First open the Channels palette using Window Channels. With the selection active in the image choose the Save .