Textile Design Studio

How to use Photoshop (Textile Design)

Photoshop…

 

  1. Introduction

    Photoshop is the industry standard for the manipulation of raster-based images. Web designers, photographs and other graphics professionals use photo shop everyday to prepare images for web pages, for print, and for use in hundreds of other imaging applications. Photoshop vast array of features and powerful special effects. On the surface, many of Photoshop tools and commands are simple and easy to use. Under the surface, however are compound techniques and infinite layers of complexity. Some of things, which photo shop includes, are: –

    1. * Customize images with special effects, editing, tools and text.
    2. * Composite images elements.
    3. * Correct and retorich photo shops.
    4. * Create professional web graphics.
    5. * Import and export images in a variety of file formats

Changing the size of an Image

One can increase or decrease the size of an image in photo shop by adjusting the pixel dimensions or by changing the resolution {the number of pixels in each inch}. Changing images pixels dimensions is called resampling. Increasing the number of pixels in an image is resampling up, where as decreasing the number of pixels is down sampling.

  • Choose image- image size. The image size dialog box appears.
  • Enabling the constrain proportions checkbox scales the image equally in both directions. If you want to adjust the horizontal and vertical dimensions independently, clear the constrain proportions checkbox. If the new dimensions you enter are not proportional, the resulting image is stretched.

Changing the canvas size

The canvas is the imaginary background on which the image sits. By changing the canvas size, the number of pixels in the image is altered, but the size of the existing images remains unchanged. No resampling occurs when changing the canvas size.

    • Changing the canvas size often is used to add additional area to an image. You can add area to one side or along the edge of the image.
  • Choose Image- Canvas size. The canvas size dialog box displays the current file size, as well as the current width and height of the image.
  • Select the units you want to use to change the canvas.
  • Enter the new width and height of the canvas.

Creating a new Image

  • Enter a filename for the new image. If you choose to leave the image untitled, you are prompted for a filename the first time you save the image.
  • Choose a height and width for the image. You can set the dimension in a variety of units. If you have image data stored on the clipboard, the size of that data is used as the default.
  • Choose a resolution for the image. If you are creating an image for onscreen display, choose 72 pixels per inch (PPI). If you are creating an image that will be printed, determine the appropriate resolution by multiplying the screen frequency by 1.5 to 2 times.
  • Choose an image mode for the image. If you will use an image mode not listed in the new dialog box, create the image first, and then convert it using image- mode.
  • Choose a colour for the background layer in the image, or choose transparent.
  • Choose o. k.

Saving Files

Photoshop can open 23 different common image file formats and save in ages in most of the same formats. When you choose save as, only some of the file formats are available, depending on the Modes and contents of your image.
Photoshop native files (PSD format) support all image modes, 24 cannels and paths. Also PSD is the only format that supports any layer information other then the background.

Saving a JPEG

When you save a joint photographic experts Group (JPEG) file, you must choose a level of compression is lossy, meaning that image. Data is discarded. You can save JPEG images in RGB and CMYK modes. Path information is stored with a JPEG image.

SELECTION

Constraining selection sizes

When you create a selection, you can constrain the selection to an exact size or define a relationship between the horizontal and vertical sizes. You can use a constrained aspect ratio for any of the marquee tools, including the Elliptical Marquee (to create circles or precisely proportioned ovals).

  • Double –click any of the marquee tools. The marquee options palette appears.
  • In the marquee options palette,
    • To set a fixed size for the marquee, select fixed size in the style dropdown list. Enter a Horizontal and vertical size.
    • To set a fixed aspect ratio for the marquee. Select a fixed aspect ratio in the style drop- down list. Enter a relationship between the width and height.
    • To return the marquee to the normal mode, select normal in the style drop down list.

Adding, Subtracting, and Selecting Overlapping Areas

After you create a selection, you can add or subtract groups of pixels. You can also create a selection set that includes only overlapping pixels from a current selection and a new selection that you create.

      • To add to a selection hold down shift while using any of the selection tools.
      • To subtract from a selection, hold down (option) (Alt) while using any of the selection tools.
      • To select overlapping areas of a new selection and an existing selection, hold down (Shift Option) (shift+Alt) while using any of the selection tools.

Making a Color- Based Selection With the Image Wand Tool

One of the most useful selection tools is the magic wand. It enables you to select a contiguous area that contains similar. You can add or subtract from a selection using the magic wand by holding down (shift and option) (Shift and Alt), respectively.

    • Double- clicks the Magic Wand tool to display the magic wand option palette.
    • Choose a tolerance value, from 1 to 255. The tolerance value determines the range of colours that photo shop adds to the selection based on the first pixel that you choose. Smaller values select a smaller range of colours larger values select a large range of colours. Colours based on a range that you set

Cropping an Image

      1. The crop tool provides a powerful method of adjusting the size o fan image you want. In addition, you can use the crop tool to rotate the new image and resize the canvas.
      2. Select the crop tool from the tool bar.
      3. Drag a rectangular area in the image to select the area that remains after the cropping operation.
      4. Resize the crop border by clicking and dragging on any of the eight handles. When dragging a handle, the border snaps to the image boundary.

Saving a Selection

After you have created a selection, you can save it with the file so that it can be reused. You can also use a saved selection in the other open images. Selections are saved as alpha channels. With the selection currently made, choose select –save selection. The save selection dialog box appears. In the name text box, enter the name of the selection.

Loading a Selection

After a selection has been saved, it can be loaded and combined with the current selection.

      1. Choose selection – Load selection. The load selection dialog box appears.
      2. In the document drop down list, choose the document from which to load the selection you can choose any open document that contains alpha channels. The default is the current document.

Making a new Brush shape

 You can create a custom brush from any shape or area that you can select. You can use custom brush shapes as stamps, or to create a variety of texture variations throughout an image.

      1. Create a selection (using any selection technique). The election must be smaller than 1000*1000 pixels. The opacity throughout the brush is based on the colour under the selection sampled. Through all visible layers. If the area under a selection is completely opaque. Where the area under the brush contains transparency or white, the brush is transparent.
      2. Choose define brush from the brushes palette menu. A preview of the new brush is displayed in the brushes palette.

After you have created a new brush, you can select it in the brushes palette and use it with any of the painting tools.

Using Layers

Photoshop’s layers provide a powerful method of organizing images and objects. You can control the way that pixel information on different layers combines using one of the many layer-blending modes. You also can control the visibility of layers not only enables you to work with selected parts image, but also to selectively save using the save a copy command.
By default, images begin with one layer called the background. Additional layers are added above the background layer. Each layer can be either independent or linked with other layers. If linked, the layers move and transform together. In addition, linked layers can be aligned and distributed. You can also apply copied-layer effects to a group of linked layers.

Editable Layer Properties

 

Property                                         Description

Name                                             Although layer names can contains up to 255 characters, keeping them less than 30                                                      characters reduces the odds that the names will be truncated in the layers palette.

Transparency                                  Change the transparency in layer options by ragging the slider in the layers pallet or by typing a                                                     number when you have one of the selection tools selected.

Mode                                             You can change the mode in layer options by selecting a mode from the list or by using one of                                                     the keyboard combinations   when you have one of the selection tools selected. The most                                                     common are: – NORMAL , MULTIPLY , SCREEN

Blends If                                         Control how pixels on a layer interact with the pixels on layers below it. This feature is not                                                     available in image ready.

Linking layers

Depending on the image you are editing, you may want to change the transparency color and the size of the transparency pattern. You can choose colors that do not appear in the image so that the areas of transparency are more apparent. Change these settings by selecting files-preferences-transparency and gamut.
By linking layers together, when one layer moves, the other moves with it. This is useful not only for maintaining spatial relationship between layers, but also for aligning layers, selectively merging layers, and pasting copied effects.

      1. * Select the layer to which you want to link by clicking the layer thumbnail in the layers palette.
      2. * Click in the ink box next to each layer that you want to link in the layers palette. Photoshop displays the link icon for the    group of linked layers whenever one of them is made active.
      3. * You can clear the layer link by clicking in the same box.

Choosing a Layer Blend Mode

Photoshop provides 17 different methods to mix the contents of a layer with those under it. The most commonly used are normal (the default mode), multiply and screen. To understand what each mode does, it is helpful to examine the effect at the pixel level.

      1. * In the layers palette, select the layer in which you want to change the blending mode.
      2. * Select a blending mode from the list in the layers palette.

 

Choose a blending mode appropriate to your task.

Blending Mode

What it does?

Uses

Normal

Replaces the pixels in the underlying layer with those on normal layer.

  This is the default mode and should be used for most straight composting.

Multiply

Multiplies the color of each pixel in the top layer with the one under it to create a darker complimentary color; multiply with black yields black; multiplying with white yields no change.

Creating shadows; darkening an image; multiply a layer by a duplicate to restore tonal density to overexposed image (adjust opacity as needed).

Overlay

Multiplies or screens, depending on the underlying color, to preserve the highlight and shadows of the underline layer; 50% gray in the underline layer yields no change.

Create texture and pattern effects; overlay the layer with a duplicate to increase
Contrast and color density (adjust opacity as needed).

Screen

Blends the color of each pixel in the screen layer with underlying pixels to create a lighter color; screening with white yields white; screening with black yields no change.

Highlights and glows; lightening an image; screen a layer with a duplicate to lighten an underexposed image. (adjust opacity as needed).

Soft light

Darkens or lightens each underlying pixels based on the light and dark values of the pixels. Above it 50% Gray in the soft light layer yields no change.

Paint with black or white to dodge or burn.

Hard light

Multiplies or screen, depending on the color in the hard light layer.

Apply hard light to a duplicate layer to increase contrast and Color density (adjust opacity as needed)

Colors dodge

Lightens and saturates the underlying pixels to match the color dodge layer.

Lightening an image.

Darken

Compares each pixels on the underlying and darken layer and uses the darker of the two.

Special effects.

Lighten

Compares each pixels on the underlying and lighten layer and uses the lighter of the two.

Special effects.

Difference

Subtracts color values of each pixels; identical pixels on the two layers yields black (0); a black and a white pixel yield white.

Special effects.

Exclusion

Similar to difference but softer effect; white pixels on the exclusion layer inverts the pixels in the underlying layer; black yields no change

Special effects.

Hue

Changes the hue of the underlying layers pixels to match those in the hue layer While leaving brightness and saturation alone.

Tinting.

Saturation

Changes the saturation of the underlying layer’s pixels to match those in the saturation layer while leaving the bright ness and hue alone.

Controlling saturation throughout an image.

Color

Preserves the gray levels in the underlying layer while replaying the hue and saturation of the underlying layer with those in the color layer.

Tinting.

Luminosity

Changes the luminosity (brightness) of the underlying layer’s pixels to match those in the luminosity layer while leaving the hue and saturation alone.

Special effects.

Color burn

Darken and desaturates the underlying pixels to match the color burn layer.

Darkening an image.

Using the History Palette

The history palette is used to move among history states, save snapshots, and set the source for the history brush. By default, the history palette is set to use linear history, so when you select a state. Subsequent states are grayed out. If you change the image from the selected state, subsequent stat are discarded.
To move backward in a document’s history, select a previous state by clicking. All subsequent states are grayed out. If you make any changes, the grayed out states are discarded, and the history begins again from the selected state or else immediately return to the previous state and restore the discarded history states.

Working with paths

Bezier paths are common to almost all illustration applications, such as illustrator, freehand, and coral Draw. These applications all use Bezier paths as the fundamental method for defining vector objects. Vector objects are defined mathematically and can be made arbitrarily large. A circle in illustrator, for example, can be made 10 times larger, and that object remains the circle. In Photoshop, on the other hand, you work primarily with pixels. A circle in Photoshop cannot be scaled up, because it consists of small squares. When scaled, the squares become larger, and aliasing is apparent.
All though Photoshop is primarily a raster based editing program. You can create Bezier paths in Photoshop. Path serves three purposes: –

      1. To create clipping paths for use in illustration and page layout application.
      2. To create selections.
      3. To create highly controllable stroke and fill effects.

Photoshop addition of the freeform pen tool and magnetic pen tool takes some of the difficulty out of creating complex paths. Many of the tools operate largely and same in Photoshop and illustrator, and the products are able to seamlessly exchange path information.
The path palette organizes the path in Photoshop documents and enables you to add, delete, rename, copy and change the visibility of paths.

Placing text

 Using the type tool, you can place. Text anywhere in an image. If you place text in an image mode that supports layers, you can preview and move the text before placing it.
Photoshop creates an editable type layer. If you place text in an image mode that does not support multiple layers (indexed color, for example) the text is placed without a preview and becomes part of the background canvas. In indexed color images, text is also aliases by default.
When you place vertical text, you can choose to place the letters horizontally or vertically by selecting rotate in the type tool dialog box.