Table of Contents
This handout will show you how to use layers to edit your image more easily and to make different parts of your image interact with one another. You will learn how to create and edit layers, how to make them transparent, and how to change their stacking order so that you see different things on the screen. You will also learn how to create special effects by changing the layer modes or by using one of the special layer effects. Finally, you will learn how to use adjustment layers and layer masks, and how to decrease the number of layers in your image through merging and flattening.
You first learned about layers by adding text to an image (see [ http://help.unc.edu/?id=3548 ] Intermediate Editing). Photoshop automatically creates a new layer whenever you use the Type tool (except for masked type); the textâs positioning in a separate layer makes it easy to manipulate independent of other parts of your image. Objects that are not in separate layers from one another, however, are not so easily to work with. In this example, the two circles are in the same layer; moving one leaves a hole, because Photoshop sees them only as one big layer, not two separate (and therefore independent) objects.
In the next example, the two circles have been created using two separate layers, making it easy to move them (and make other editing changes) without affecting the other. You can think of a layer like a transparency sheet that you put on an overhead projector. Although only the diagram on the transparency sheet is visible, the transparent areas still exist and are still part of your layer. To take this analogy further, consider animations: when you see Mickey Mouse trotting through the woods, what youâre actually seeing is Mickey in one layer, or on one sheet of transparency, while the woods are on another sheet, behind Mickey. You can move the two independently because theyâre in different layers.
You should know that layers, because theyâre so powerful, take up a good deal of RAM. As you already know from [ http://help.unc.edu/?id=3464 ] Image Correction, the .psd file type is one of the few file formats that can save layers for future editing, and no program other than Photoshop will be able to âseeâ your layers. Finally, certain color modes (such as Indexed Color) are incompatible with layers.
On the bottom floating palette, click on the Layers tab to bring the layers palette to the front. (If the palette does not appear on the screen, go to the Window menu and select Layers .) The palette will list the layers in the image and provide a thumbnail of each layer's contents. To the left of each layer name are two columns of icons. The eyeball on the far left indicates which layers are currently visible in your image. Click the eyeball off to make a layer temporarily invisible. The second column of icons shows a paintbrush next to the active layer and a chain next to any layers linked to it. To select a layer to edit, simply click on its name.
You may also notice a row of icons at the bottom of the palette. The first four are specific to the Layers palette; the last two, however, should look familiar. The New icon is one way to create a new layer, and the trash can is one way to dispose of layers you wish to delete. Weâll cover the rest of the icons along the bottom, as well as the other options on this palette, in the remainder of the handout.
Unless the image is created with a transparent background, it will initially have at least one layer, called the Background . The background is the lowest layer of an image and the only layer that applications other than Photoshop can read. Because it is special, features that you can ordinarily use with layers will not work on it. In order to make adjustments to the layer, you will need to double-click on its name in the Layers palette and rename the layer (by default, its name will be Layer 0 ). You can then set opacity levels, move the layer, or perform other commands (as detailed below). Should you want to insert a background layer later in your editing, you can choose the Background from Layer command from the New submenu of the Layer menu.
There are many ways to create a new layer:
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From the Layer menu, select New and then Layer . This brings up the New Layer dialog box, and you can select the Opacity and the Mode for the layer as well as color-code it as part of a layer set (more on these later).
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Click the New Layer icon on the Layers palette. Then add whatever contents you want to the layer. Hold down the <Alt> button as you click to bring up the New Layer dialog box. Alternatively, to rename a layer later on, double-click on the layer name in the Layers palette.
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To create a new layer from part of an existing layer, first make your selection. Then use the Layer via Copy command from the New submenu of the Layer command to create a new layer containing a copy of the selection. To remove a selection from its original layer and place it in a new layer, use Layer via Cut .
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To duplicate an existing layer, select it in the layers palette and drag it down until it touches the New Layer icon, or choose the Duplicate Layer command from the Layer menu.
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Anytime you move a selection (or an entire image) from one document window to another, it will automatically be added in a new layer.
When a new layer is created, it will appear as the top layer in the image, and it will be completely transparent except for any objects existing in it or added to it. For blending modes other than Normal, you will have the option to fill the layer with a neutral color, which you will want to do if you want to apply a filter to a layer.
Whenever you use the Type tool to add text to an image, it appears in a new layer. This feature allows you to move and edit the text through the Layers palette. When you want to work with text as a layer, however, you'll need to perform an extra step. Because Photoshop considers text layers different from non-text layers (a difference you'll see in the Layers palette, where text layers are marked with a "T" to the left of their names), you have the flexibility of editing text layers.
When you want to perform certain commands on text layersâfor example, locking transparent pixelsâyou will need to ensure that Photoshop treats a text layer just as it would any other layer; that is, you'll need to give up the ability to edit the text in the future. To do so, you will need to select the Rasterize command from the Layer menu, then choose Type . Once you rasterize the text, you canât edit it, but you can use all the features discussed below.
You can choose a layer by clicking on its name in the Layers palette. You can also use the Move tool in two different ways to select the layer you want to work with. First, you can check on the Auto Select Layer feature in the Move options bar. This feature automatically selects whichever layer contains a non-transparent object when you click.
You may find that a more reliable way to select the layer you want with the Move tool is to turn off the Auto Select Layer feature and to instead right-click on an object in the layer you want to work with. Photoshop will bring up a shortcut menu of all the layers you might possibly want to choose, and you can select directly from that menu, rather than having to use the Layers palette.
Once a layer is selected, you can use the move tool to change the layer's location in the image. You move everything in a layerâopaque objects as well as transparent areasâwhen you click and drag on it with the Move tool.
Note that when you edit part of an image, perhaps by applying a filter or using one of the tools in the toolbox, any changes or selections will only apply to the active layer. Several tools do give you the option of applying the effect to the entire image at once; simply check the Use All Layers box in the tool's options bar.
To delete a layer, select it in the Layers palette, and click on the trash can (the bottom right icon).
You may have noticed that some layers in your image appear to be on top of other layers. The layer listed at the top of the Layers palette will appear on top of any layers beneath it. To reorder your layers, simply click and drag the layer names in the Layers palette (you won't be able to perform this function with the Background layer). The Arrange option in the Layer menu can also be used to reorder layers; select the layer you want to move, then choose the command.
The Layer Opacity determines how much you can see through the layer, and it is the easiest way to blend layers. If you create a new layer using the menu, you can set the opacity in the New Layer dialog box. You can also set the opacity by selecting the layer and using the opacity slider in the Layers palette.
Fill opacity affects pixels painted in a layer or shapes drawn on a layer without affecting the opacity of any layer effects that have been applied to the layer.
As we learned in [ http://help.unc.edu/?id=3548 ] Intermediate Editing, blending modes alter the way that paint gets applied to your image. In the case of layers, blending modes affect how the layer interacts and blends with the visible layer directly beneath it. The drop-down menu in the Layers palette lists the different options. The default blending mode is Normal , which works as if the layer is the only thing in the image, so it does not interact with the layers beneath it.
There are more apply modes than we can cover here, but we will provide a few examples so that you have an idea of how they work. (You may also consult the exhaustive list in [ http://help.unc.edu/?id=3548 ] Intermediate Editing). The best way to see what a blending mode does is to try it out.
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Dissolve : Makes the image break up as you lessen the opacity.
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Multiply : Multiplies the colors in the layer by the colors in the layer below it. Anything multiplied with black yields black; anything multiplied with white keeps its original colors. All other colors get darkerâjust how dark depends upon the color in the layer beneath it.
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Screen : Does the opposite of Multiply mode.
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Overlay : Creates the effect of placing a transparent, but colored, overlay over an image. Highlights and shadows are unaffected, but midtones accept the overlaid color.
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Hard Light : Makes objects look as if a strong light is shining through them.
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Color Dodge and Color Burn : Work the same way as the dodge and burn tools do to lighten and darken the entire layer based on the layer beneath it.
The Lock Transparent Pixels option prevents any changes from affecting pixels in the transparent areas; instead, you can only alter opaque pixels that already exist in the layer. This feature can be helpful when you are filling an opaque area (you wonât need to worry about selecting it) or when you are painting in layers.
This feature prevents any changes to the opaque areas of a layer with the painting tools or any fill tool (such as the gradient or paint bucket). It also automatically locks the transparent pixels in the layer.
As the name implies, this feature prevents the layer from movement with the Move tool.
This is a way to quickly lock all three of the above features. When you have all options locked for a layer, youâll see a solid lock icon next to the layer name on the Layers palette. If you have between one and three features locked, youâll see a hollow lock icon instead.
Linking layers enables you to move and manipulate the objects in multiple layers at once. To link two or more layers, first select one of the layers. Then click in the link column next to the layer or layers you want to link it to so that the chain icon appears. Now, when you move one of the linked layers, the others will move as well. To turn off the link, click in the link column next to the layer you do not want linked, or select an unlinked layer. It is possible to link and move everything including the background layer, but be aware that the more layers you link, the more slowly Photoshop works.
You may sometimes need to align objects in different layers or to distribute several objects equally throughout your image, particularly when youâre working with text. These tasks are easily accomplished using commands from the Layer menu. First, select the layer (from your Layers palette) that contains the object you want to use as a guide. (That is, you want everything else to line up to match it.) Then link the layers you want to align or distribute by clicking in the column just to the left of the layer name.
Finally, choose the command you needâeither Align Linked or Distribute Linked âfrom the Layer menu. You can repeat the commands as many times as necessary (for example, to line up both rows and columns of objects).
Note : these commands will only work if the objects in your layers are at least 50% opaque; otherwise, Photoshop may not recognize them as objects and won't be able to align or distribute them.
To lock several layers at a time, to work with a number of layers as if theyâre one, or just to reduce clutter on your Layers palette, you may choose to work with a layer set. One way to create a layer set is to link the layers you want to include in the set, then choose the Layer Set from Linked from the New submenu of the Layer menu. Alternatively, you can create a layer set folder, then drag the layers you want to include into the folder. By default, the layers in a set will be in Pass Through mode, which makes them appear just as they did before they were included in the set. Changing the blending mode for the set means that Photoshop will change each layer thatâs part of the set first, then adjust the layers surrounding the set second. If you no longer want the layers to be part of a set, you can choose Delete Layer Set from the Layer menu; youâll be given the option to delete the set and the contents, or just the set.
When you copy part of one image into another, you will frequently need to manipulate the layer so that it blends into the new image. You can easily resize, reposition, or distort the new layer by selecting Transform from the Edit menu and choosing the appropriate option. A bounding box will appear around the opaque area of the layer; it works much like the crop lines of the Crop tool. With the mouse, click and drag on the handles to preview the effect. When you want to apply the effect to your image, press the check mark in the Options bar; to cancel your work, click on the slashed circle icon.
To resize a layer, choose Scale from the Edit, Transform menu, and then click and drag on the handles. Hold down the <Shift> key as you drag to preserve proportionality.
Use the Skew command to slant an image, Distort to stretch an image in different directions, and Perspective to create the appearance of depth in an image. Note that when you use the Perspective command, as you drag on one handle, another one will move in the opposite direction, creating a depth effect.
The Flip and Rotate commands can position objects at the correct angle and facing the correct direction. You can also choose Rotate from the menu, which will allow you to click and drag on the layer to rotate it to any angle. To change the center point for the rotation, click and drag on the center point icon before rotating.
You have already learned about working with some basic filters from [ http://help.unc.edu/?id=3464 ] Image Correction. While some filters, such as the Sharpen, Blur and Dust and Scratches filters, work fine on a single-layer image, others work best when you apply the filter to a selection in a separate layer from the rest of the image. In this section, we'll cover a handful of filters that work best in conjunction with layers; as you can see from the number of filters Photoshop offers, the possibilities are much more extensive than we could discuss here.
An important principle to remember when working with filters in layers is that almost no filter works on an empty layerâthat is, one that is merely transparent (the kind of layer you get when you simply click on the New Layer icon to add a layer to your image). In most cases, you will need to add a layer using the Layer command from the New submenu of the Layer menu.
If you change the blending mode from Normal (to any of the other blending mode options) in the dialog box that appears, you will then have the option to fill the layer with a neutral fill color by checking the box next to that option. Because the fill color will be neutral, you will not see any change to your image on the screen. When you apply a filter, however, you will be able to see the changesâand then control them using the opacity slider and blending modes for the layer.
A good way to get your feet wet is to use the Clouds filter from the Render menu. This is the only filter in Photoshop that will let you work with an empty layer, so you need not worry about adding a neutral fill. First, create a new layer for your image. Then apply the Clouds filter; it will create a cloud-shaped blend of your foreground and background colors. You can then adjust the opacity of the clouds in the Layers palette. For even more control over the clouds, select a particular area of an image before creating a new layer; the filter will then be applied only in the selection area.
A good example of a filter to use on a selected object is the Motion Blur filter, part of the Blur group. This filter tends to work best when you select the object from the image that should look as if it's moving. Create a new layer from that selection using Layer via Copy . In the new layer, apply the Motion Blur filter. You can then move the object in that layer slightly to enhance the illusion of motion (setting it off from the object in the background layer), and adjusting the opacity for the filtered layer may further enhance the effect.
Finally, a good filter to use on a layer filled with a neutral fill color is Texturizer , available from the Texturize group. In the dialog box, set the texture youâd like to apply, along with the relief and scaling settings, then click OK . You can now control the filterâs effects using the Opacity slider and by changing the blending mode.
While filters offer you one way to create effects for your image, layer styles offer another. Once you have an object or text in a layer, go to the Layer menu, choose Layer Style , and click on the effect you want. The Layer Style dialog box will appear, and from it you can select any effect from the list on the left by checking the box next to it, then making adjustments in the center box if you want them. You can choose to use as many or as few styles as you like. When youâve completed your layer style selections, click OK .
Notice that in the layers palette, an f appears next to any layer with a style (previously called âeffectsâ) on it. To edit an effect, double-click on the f, which will bring up the Effects dialog box, or click on the f icon at the bottom of the Layers palette. Layers with layer styles will list each style beneath the layer to which theyâve been applied; to collapse the list, click on the triangle to the right of the layer name. You may also want to break up each style into separate layers using the Create Layers command from the Layer Style submenu of the Layers menu. This way you can control the opacity and blending mode for each layer.
Not all effects will translate well into separate layers, however, so be aware that performing this command may change the way your image looks.
Photoshop offers two ways to copy the styles from one layer to other layers. To copy effects to only one layer, select the layer with the effects, then choose Layer, Layer Style , and Copy Layer Style . Now select (from the Layers palette) the layer to which you'd like to add the effects, and choose Layer, Layer Style , and Paste Layer Style . To copy effects to several layers, select the layer with effects in the Layers palette, then link the layers to which you want to copy the effects. Now choose Layer, Layer Style , and Paste Layer Style to Linked . Photoshop will automatically paste the effects from the initial layer to all the layers linked to it.
Layer masks offer ways to blend two (or more) very different images together through layers. First of all, a mask, as we learned in [ http://help.unc.edu/?id=3718 ] Selection Techniques, is something that covers up an area of an image. Layer masks selectively cover an area of one layer with an image from another layer. In other words, using a layer mask, you can blend your vacation picture from the Grand Canyon on a rainy afternoon into a picture of a beautiful sunset, and make it seem as if the vacation took place against a stunning backdrop.
When using a layer mask, itâs important to remember that there are two basic types: Reveal All and Hide All . Just as their names imply, the Reveal All type will completely display whichever layer is âon topâ in the Layers palette; conversely, the Hide All type will completely cover it up with the other layer. When you work with a Reveal All mask, you should always paint with black as your foreground color; with a Hide All mask, you should always paint in white.
Youâll need to have at least two layers in your image before you can add a layer mask. An easy way to add a new layer to an existing image is to simply use the Move tool to move a copy of another image onto the existing file. Photoshop will automatically create a new layer for the new image. You can then choose Add Layer Mask from the Layer menu; choose Reveal All or Hide All , depending on what you want to do.
In your Channels palette, you should now see a new channel called Layer 1 Mask . Your Layers palette will look unusual, too: Layer 1 (the layer you added to the original image) will now have two parts, the original image thumbnail and a mask thumbnail (black-and-white). They are linked together, and there is a layer mask icon to the left of the layer name, indicating that the layer mask is currently in effect. To edit your image using the layer mask, do not unlink the mask from the layer or turn off the layer mask icon.
If you have chosen Reveal All, you will now see the new image layer on top of (or completely covering, depending on its size) the original image layer. Choose the Paintbrush tool from the toolbox and set the foreground color to black. Make sure that your opacity is set at 100% and your blending mode is Normal. Now, with a large soft brush, begin painting over your image. You will begin to see the original image through the new layer. Continue painting until you have painted in all areas of the original image that you want to âshow throughâ the new layer.
If you make a mistake, you can paint the new layer back in by using white as your foreground color. (If you chose a Hide All mask type, paint using white as your foreground color to paint the new layer into the original image, and correct mistakes using black paint.) To catch any spots you may have missed, pull forward the Channels palette and make the Layer Mask channel the only visible layer; youâll be able to see your masking work in black and white.
Fill layers and adjustment layers offer you ways to add effects to your image that you can control easily by adding them in a separate layer. If you select a fill layer, you have the option of filling the layer with a solid color, gradient, or pattern. To add a fill layer, either choose the New Fill Layer command from the Layer menu or use the icon at the bottom of the Layers palette. You will then have to select the type of fill you want to create.
Once you select one of these options, Photoshop will prompt you to name the layer, then set the fill effect options. The new layer will be added as a kind of layer mask on the Layers palette; you can now control it using all of the options discussed above.
As the name would imply, you can add an adjustment layer to your image to make subtle tonal adjustments. All of the adjustment layers offer options that are already available to you through the Adjustments submenu of the Image menu; the advantage of using adjustment layers to apply these commands, though, is that you can make subtle changes in the opacity and blending mode of the adjustment layerâoptions that werenât available to you via the Adjustments commands.
To add an adjustment layer to your image, choose New Adjustment Layer from the Layer menu. You can select the type of layer youâd like from the drop-down menu, then proceed to the New Layer dialog box. By default, the layer will be named after the adjustment, but you can override it by selecting the name and typing a new one. You can also set the Mode and Opacity for the layer here. Once you click OK, youâll see a new layer on the Layers palette; it will have a special icon specific to its function.
Note two special features of the adjustment layer: first, you cannot lock image or transparent pixels for the layer (because it has no opaque objects in it), and second, in the column to the left of the layer is an icon indicating that the layer is masked. You can adjust the opacity and the blending mode of the adjustment layer in the Layers palette just as you would any regular layer.
Most adjustment options are covered in the Image Correction handout, so hereâs a brief recap:
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To make adjustments to the tonal levels of your image (black & white), use Levels, Curves , or Brightness and Contrast .
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To make adjustments to the color levels in your image, use Color Balance, Hue/Saturation, Selective Color , or Channel Mixer .
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To create special effects such as color inversions, black-and-white renderings of the highlights, and making your image look like an Andy Warhol painting, use Invert, Threshold , and Posterize , respectively.
As more layers are added to an image, more RAM is required to manipulate that image. You may occasionally want to merge layers together so that your computer will manage editing more quickly. Be aware, though, that once layers are merged or flattened, there is no easy way to get the original layers back, so additional editing will be more difficult. When your editing is finished, remember that itâs smart to save one version with layers as a .psd file for easy editing in the future, even if youâre eventually going to save the image as a .jpeg or .gif.
You have three options for merging layers. If you have any layers linked in the Layers palette, you can choose Merge Linked to merge the two together. If you select Merge Visible from the Layer menu, Photoshop will merge all visible layers (those with the eye icon next to them in the layers palette) onto the background (if the background is visible). If the background is hidden, Photoshop will merge the visible layers onto a new layer. If you select Merge Down from the Layer menu, Photoshop will merge the active layer or layers (if they are linked) into the layer (or background) immediately below it on the list in the layers palette. Merge Down is particularly useful when you have just pasted a new object onto an image.
When you duplicate your image using the Image, Duplicate command, you have the option of duplicating Merged Layers Only. If you check this box, Photoshop will flatten the image so that the copy has only one layer. This is a good way to make a flattened copy of your image without sacrificing a version of the file which maintains all the layers.
Since the background layer is the only layer that applications other than Photoshop can read, you must "flatten" the image before you open it or place it into another programâthat is, you must merge the layers into the background layer. To flatten an image, first make sure that all layers that you want to save are visible (the eyeball icon must be showing in the Layers palette). Then select Flatten Image from the Layer menu. The image appearing on the screen will become part of the background, and any hidden layers with be discarded, leaving you with just the new background layer. If there is no background layer in an image, Flatten Image will create one and give it a background color of white.
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Thank you so much for these instructions; I desperately needed to find out how to add text to some very old photos, but found nothing but highly technical instructions geared to professionals until I came upon your site. I am pleased to say that after reading just 4 short paragraphs on adding text in photoshop, I had my problem solved (about 5 minutes with your very concise outline..Thanks so much! JD p.s.sorry about that first blank submission.