There’s a common saying among artistic types who use software in their studios: Tools don’t equal talent. And it’s true: No mere computer program is going to turn a klutz into a Klimt. But Elements has some special tools—filters, effects, and Layer styles—that can sure help you fool a lot of people. It’s amazing what a difference you can make in the appearance of an image with only a couple of clicks.
Filters are a jaw-droppingly easy way to change how photos look. You can use certain filters for enhancing and correcting images, but Elements also gives you a bunch of other filters that are great for unleashing all your artistic impulses, as shown in Figure 13-1. (You can find the original photos—rooftops.jpg and bauhinia.jpg—on this book’s Missing CD page at www.missingmanuals.com/cds if you want to play around with them yourself.)
Most filters have settings you can adjust to control how the filter changes your photo. Elements comes with more than a hundred different filters, so there isn’t room in this chapter to cover each filter individually, but you’ll learn the basics of applying filters and get in-depth coverage of some of the ones you’re most likely to use.
Effects, on the other hand, are like little macros or scripts designed to make elaborate changes to your image, like creating a three-dimensional frame around it or making it look like a pencil sketch or an oil pastel. (Adobe calls them Photo Effects, but you can apply them to any kind of image, not just photos.) They’re easy to apply—you just double-click a button—but you can’t tweak their settings as easily as you can with filters, since effects are programmed to make specific changes.
Figure 13-1. Elements’ filters let you add all sorts of artistic effects to your photos. Here you see two plain photos on the left, and two examples of how you can transform them with filters on the right. In both cases, several filters were applied to build up the effect. Top: These figures show how you can make a photo resemble a colored-steel engraving. Bottom: These figures show how you can create a watercolor look.
Note
If you’ve used Elements before, you may know that the effects are also called actions. Full-featured Photoshop lets you record and save your own actions and install actions created by others. Elements has an actions player so you can use certain Photoshop actions in Elements, but you can’t create actions in Elements.
Elements also gives you some spiffy new special effects in Guided Edit. If you’ve been using Elements for a while, you may think Guided Edit is just for beginners, but now there’s plenty there even if you’re an old pro. You can use it to create elaborate effects like the Apple-style reflections you see in so many ads these days, make your image look like it’s made from a pile of separate photos, create fancy glamour-style portraits, or make a pop-art image à la Warhol. Special Effects in Guided Edit has the lowdown.
Layer styles change the appearance of only one layer of your photo (see Chapter 6 for more about layers). They’re great for creating impressive-looking text, but you also can apply them to objects and shapes. Most Layer styles include settings you can easily modify.
If you want to get really creative, you can combine filters, effects, and Layer styles on the same image. You may end up spending hours trying different groupings, because it’s addicting to watch the often unpredictable results you get when mixing them up.
The last section of this chapter focuses on gradients. A gradient is a rainbow-like range of color that you can use to color in an object or a background. You can also use gradients and gradient maps—gradients that are distributed according to the brightness values in your photo—for precise retouching effects.
Filters let you change the look of photos in complex ways, but applying them is as easy as double-clicking. Elements gives you a ton of filters, grouped into categories to help you choose one that does what you want. This section offers a quick tour through the filter categories and some info about using a few of the most popular filters, like Noise and Blur.
To make it easy to work with filters, Elements lets you apply them from two different places: the Filter menu and the Effects panel. (The menu is the only place where you can see every filter; some filters, like the Adjustment filters, don’t appear in the panel.) Elements also includes the Filter Gallery, a great feature that helps you get an idea of how your photo will look when you apply the artistic filters. Keep reading to learn about all three methods.
In the Filter menu, you choose a filter from the list by category and then by name. In the Effects panel, thumbnail images give you a preview of what the filters do by showing how they affect a picture of an apple.
The cool thing about the Filter Gallery is that it shows you a preview of what a filter looks like when applied to your image. Some filters automatically open the Filter Gallery when you choose them from the menu or the panel, though you can call up the Gallery without first choosing a filter by going to Filter→Filter Gallery. You can’t apply every filter from the Gallery—only some of the ones with adjustable settings.
Tip
You can easily apply the same filter repeatedly: Press Ctrl+F/⌘-F and Elements applies the last filter you used, with whatever settings you last used. The top item in the Filter menu also lists the name of this filter (selecting it has the same effect as the keyboard shortcut: Elements applies that filter with the same settings you last used).
The filters do the same thing no matter which way you choose them. The next few sections explain your options in more detail.
The Filter menu groups filters into 13 categories (Correct Camera Distortion [Correcting Lens Distortion] is all by itself at the top of the list, not in a category). There’s a divider below the bottom category (Other). When you first install Elements, the Digimarc filter is the only filter below this line, but other filters you download or purchase will appear here, too.
When you choose a filter from this menu, one of three things happens:
Elements applies the filter. This happens if the filter’s name doesn’t have an ellipsis (…) after it. Just look at the result in your photo, and if you don’t like its effect, press Ctrl+Z/⌘-Z to undo it. If you do like it, you’re done.
You see a dialog box. Filters that have adjustable settings have an ellipsis (…) after their names in the Filter menu. These filters (mostly corrective filters, like Dust & Scratches) open a dialog box where you can tweak their settings. Adjust the settings while watching the small preview in the dialog box to see what you’re doing, and then click OK.
You see the Filter Gallery. Some of the more artistic, adjustable filters call up the Filter Gallery so you can see a large preview of what you’re doing and rearrange the order of multiple filters before applying them. The Filter Gallery explains how to use the Gallery.
Regardless of how you apply a filter, if you’re not happy with its effect, you can undo it by pressing Ctrl+Z/⌘-Z. If you like it, just save your image.
If you’re more comfortable with visual clues when choosing a filter, you can also find most filters in the Effects panel (Figure 13-2), which is, logically enough, also where you apply effects (Adding Effects).
The Effects panel shows up in the Panel bin the first time you launch Elements. If it’s not there waiting for you, go to Window→Effects, and then click the Filters button (circled in Figure 13-2). To find a filter, select a category from the drop-down menu or choose Show All. The categories are the same as the ones in the Filter menu, except that Adjustments is available only through the menu, and Sharpen appears in the panel but not the menu. To apply a filter from the panel, double-click its thumbnail or drag the thumbnail onto your image, or click the thumbnail of the one you want and then click Apply.
Figure 13-2. The Effects panel shows you what every filter looks like when applied to the same picture of an apple. Click the Filters button (circled), and then, from the drop-down menu (the one that says “Artistic” here), choose a category. If you know what you want a filter to do but don’t know what it’s called, scrolling through these thumbnail images can help you find the one you want. To apply a filter from this panel, double-click the appropriate thumbnail; click the thumbnail once and then click the Apply button; or drag the filter’s thumbnail from the panel onto your image.
One drawback to applying filters from this panel is that you don’t get a chance to adjust their settings. If the filter is one that has a dialog box or settings in the Filter Gallery, you don’t see those here—Elements just applies the filter to your photo using the filter’s current settings.
The Filter Gallery (Filter→Filter Gallery), shown in Figure 13-3, is a popular feature. It gives you a large preview window, a look at all the green-apple thumbnails so you can tell what each filter does. and (most importantly) it lets you apply filters like layers: You can stack them up and change the order in which Elements applies them to the image. Changing the order can make a big impact on how filters affect images. For example, you get very different results if you apply Ink Outlines after the Sprayed Strokes filter rather than the other way around. The Gallery makes it easy to play around and see which order gives you the look you want. The layer-like behavior of the filters in the gallery is only for previewing, though—you don’t end up with any new layers after you apply the filter(s).
The Gallery is more for artistic filters than corrective ones. You can’t apply the Adjustment or Noise filters from here, for instance. All the Gallery filters are in the artistic, brushstroke, distort, sketch, stylize, and texture categories. (The next section includes an overview of all the filter categories.)
The Filter Gallery window is divided into three panes. On the left is a preview of what your image will look like when you apply the filter(s). The center panel holds thumbnails of the different filters, and the right side contains the settings for the current filter. Your filter layers are at the bottom of the settings pane, where you can see what filters you’ve applied, add or subtract filters, and change their order.
Figure 13-3. Elements’ Filter Gallery. For an even larger preview, click the triangle button in the window’s upper right (labeled) to collapse the thumbnails and regain that section for preview space.
Note
You don’t create any new, permanent layers when you use the Filter Gallery. Filter layers work something like regular layers (see Chapter 6), but they’re just what you might call “working layers:” They’re only to help you figure out which order to apply filters in; they don’t actually become new layers in your image. In other words, you have separate filter layers only until you click OK in the Filter Gallery; then all your chosen filters get applied to the image in the order you chose. You can’t apply the filters, close your photo, come back later, and still see the filters as individual, changeable layers. And most important, your filters become part of the layer to which you apply them.
Also, if you’ve used a recent version of the full-featured Photoshop, be aware that Elements doesn’t create editable smart filters the way Photoshop does—it handles filters the way earlier versions of Photoshop (CS2 and below) did. Keep this in mind if you’re trying to do something based on instructions written for Photoshop (directions you’ve found online, say).
In addition to letting you adjust the settings for a given filter, the Filter Gallery lets you perform a few other tricks:
Adjust your view of the image. In the Gallery’s lower-left corner, click the percentage or the up/down triangles (you only see one triangle in Windows) next to it to bring up a list of preset views to choose from. You can also click the + and – buttons to zoom in or out. Easier still, use the Ctrl+=/⌘-= (the Ctrl/⌘ key plus the equal sign key) and Ctrl+–/⌘-– (the Ctrl/⌘ key plus the minus key) shortcuts to zoom in and out with your keyboard.
Choose a new filter. Click a filter’s thumbnail once, and Elements displays the settings for that filter and updates the image preview—usually. (See the box on Filter Performance Hints for details.)
Add a new filter layer. Each time you click the New Filter Layer icon (see Figure 13-4), Elements adds another filter layer.
Figure 13-4. If you’ve used layers before (see Chapter 6), these circled icons should look familiar. In the Filter Gallery, the one on the left makes new filter layers instead of regular layers. Click it to add a new filter layer to your image, or the trashcan icon to delete a filter layer. The eye icons next to each filter layer turn visibility on and off just as they do in the Layers panel. Remember, filter layers don’t show up as real layers in the Layers panel—only in the Filter Gallery.
Change the position of filter layers. Drag them up and down in the stack to change the order in which Elements will apply them to your image.
Hide filter layers. Click the eye icon next to a filter layer in the filter-layer panel to turn off its visibility, as in the regular Layers panel.
Delete filter layers. Select any filter layer by clicking it, and then click the trashcan icon to delete it.
Change a filter layer’s content. You can change what kind of filter is in a particular layer. For instance, if you applied several filters and wish you could change the Smudge Stick filter to the Glass filter, you don’t have to delete the Smudge Stick layer; just select it and then click the Glass filter button to change that layer’s contents.
Elements divides filters into categories to help you track down the one you want. Some categories, like Distort, contain filters that vary hugely in what they do to your photo. Other categories, like Brush Strokes, contain filters that are obviously related to one another. Here’s a breakdown of the categories:
Correct Camera Distortion. This isn’t actually a category, but rather a single filter that lets you correct perspective distortion (think tall buildings) as well as vignetting (shadows) caused by your camera’s lens. It’s explained in detail on Correcting Lens Distortion.
Adjustments. These filters apply photographic, stylistic, and artistic changes to your photo. Most of them are explained on Special Effects; the Photo Filters are covered on Photo Filter.
Artistic. This huge group of filters can do everything from giving your photo a cut-from-paper look (Cutout) to making it resemble a quick sketch (Rough Pastels). You generally get the best results with these filters by using multiple filters or applying the same one several times.
Blur. These filters let you soften focus and add artistic effects. They’re explained on Gaussian Blur: Drawing attention to an object.
Brush Strokes. The filters in this category apply brushstroke effects and create a hand-painted look.
Distort. These filters warp images in a variety of ways. The Liquify filter is the most powerful; Applying the Liquify Filter to Text explains how to use it.
Noise. Use these filters to add or remove grain. They’re explained on Removing noise: Getting rid of graininess.
Pixelate. These filters break your image up in different ways, making it show the dot pattern of a magazine or newspaper’s printed image (Halftone), or the fragmented look you see on television when a show conceals someone’s identity (Mosaic).
Note
The Color Halftone filter makes your image look like it’s made of many dots of color, like a magazine photo or other printed illustration, or comic-style pop art. But, it’s not the same as true halftone screening, which Elements can’t do. So if the print shop you’re working with needs a halftone, you need to either use the full-featured Photoshop or ask the printer to create the halftone for you.
Render. This group includes a diverse bunch of filters that let you do things like create a lens flare effect and make your image look like fibers or clouds. The Lighting Effects filter, a powerful but confusing filter that’s like a whole program in itself, helps you change the way lighting appears in your image. For a full rundown on what this filter does and how to use it, check out this book’s Missing CD page at www.missingmanuals.com.
Sharpen. This category, which contains only the Unsharp Mask filter (Unsharp Mask), appears in the Effects panel but not the Filter menu. (The sharpening commands are in the Enhance menu instead.)
Sketch. These filters can make your photo look like it was drawn with charcoal, chalk, crayon, or some other material, or like it was embossed in wet plaster, photocopied, or created with a rubber stamp.
Stylize. These filters create special effects by increasing the contrast in your photo and displacing pixels. They can make your photo look radioactive, like the objects in it are moving quickly, or reduce it to outlines.
Texture. These filters change the surface of your photo to look like it was made from another material. Use them to create a cracked finish, a stained-glass look, or a mosaic effect.
Video. These filters are for creating and editing images for (and from) videos.
Other. This is a group of technical, customizable filters. The High Pass filter is explained on The High-Pass Filter. You can use Offset to shift an image or a layer a bit, or to position tiled image layers.
Digimarc. Digimarc is a company that lets subscribers enter their info into a database so that anyone who gets one of their photos can find out who holds the copyright. You can use this filter to check for Digimarc watermarks in photos.
You can find a number of filter plug-ins online, ranging from free to very expensive. Stuff from the Internet suggests some places to start looking. When you install new filters, they appear at the bottom of the Filter menu.
Note
Filters are platform specific, which means you can’t use plug-ins written for the Windows version of Elements if you’re on a Mac and vice versa. And for Elements 10, Mac plug-ins have to be written specifically for Intel Macs; plug-ins written for older PowerPC Macs won’t work (see Scanning Photos).
This section covers how to use some of Elements’ most popular and useful filters to correct photos and create a few special effects. For instance, you’ll learn how to modify graininess to create an aged effect or smooth out a repair job. And you’ll find out how to blur photos to create a soft-focus effect or make objects look like they’re moving.
Noise, undesired graininess in an image, is a big problem with many digital cameras, especially ones that have small sensors and high megapixel counts, like most recent point-and-shoot cameras. It’s rare to find a fixed-lens camera with more than 5 megapixels that doesn’t have some trouble with noise, especially in underexposed areas.
If you shoot using the Raw format, you can correct a fair amount of noise right in the Raw Converter (Adjusting Sharpness and Reducing Noise). But the Converter may give unpredictable results if you use it on JPEGs. And even Raw files may need further noise reduction once you’ve edited a photo after converting it.
Elements’ Reduce Noise filter is (not surprisingly) designed to help get rid of noise in photos. To run this filter, go to Filter→Noise→Reduce Noise. You get a dialog box with a preview window on the left and settings on the right. To apply the filter, first use the controls below the preview to set the zoom level to 100 percent or higher. (You need to see the individual pixels in your photo so you can tell how the filter is changing them as you adjust the settings.) Then, adjust the filter’s three sliders:
Strength. This controls the overall impact of the filter, which reduces the same kind of noise as the Luminance Smoothing setting in the Raw Converter (Adjusting Sharpness and Reducing Noise). The higher this setting, the greater the risk of softening your photo.
Preserve Details. Using noise reduction can soften your photo and make it look blurry. This setting tells Elements how much care to take to preserve details.
Reduce Color Noise. This control adjusts uneven color distribution in your image. You can set the slider pretty high without harming the photo.
The Remove JPEG Artifact checkbox tells Elements to minimize JPEG artifacts—the uneven areas of color caused by JPEG compression (see About JPEGs). A mottled pattern in what should be a clear blue sky is a classic example of JPEG artifacting. Turn on this checkbox to help smooth things out.
For each setting, move the slider to the right if you want it to have more of an impact and to the left if you want less. Watch the effect in the preview window to see the changes. (You may notice a little lag time before the preview updates.) When you like what you see, click OK to apply the filter.
The Reduce Noise filter does an OK job on areas with a small amount of noise, like the sky in many JPEG photos, but it’s not one of Elements’ best tools. If your camera has major noise problems, you may need special noise-reduction software to tackle it. Some of the most popular programs are Noise Ninja (www.picturecode.com), Neat Image (www.neatimage.com), Topaz (www.topazlabs.com), and Noiseware (www.imagenomic.com), which all have demo versions you can download to try them out. If you search on Google for “noise reduction software,” you’ll get a variety of other options as well, including several free programs.
Elements also gives you a filter for creating noise. Why do that when most of the time you try to get rid of noise? One reason is when you’re trying to age your photo: If you want to make it look like it came from an old newspaper, for instance, you’d add some noise.
Another common use for noise is to help make repaired spots blend in with the rest of an image. If you’ve altered part of a photo in Elements, especially by painting on it, odds are good that the repaired area looks perfectly smooth. That’s great if the rest of the photo is noise free, but if the photo is a little grainy, that smooth patch will stand out like a sore thumb. Adding a bit of noise makes it blend in better, as shown in Figure 13-5. Also, if you see color banding when you print, adding a little noise to the photo may help fix that.
Figure 13-5. Top: If you use the Average Blur filter in a repair on this noisy photo, the blended area stands out, making the repair obvious. Bottom: By adding some noise, the change becomes much less noticeable.
To add noise to a photo, start by selecting the area you want to make noisier. Using a duplicate layer (Ctrl+J/⌘-J) for the noise is a good idea, since you can always undo changes if they’re on their own layer. Here’s what you do:
The Add Noise dialog box has three settings:
Amount. This controls how heavy the noise will be. Drag the slider to the right for more noise or to the left for less. You can also type in a number; a higher percentage means more noise.
Distribution. These buttons control how Elements distributes the noise in your image. Uniform is just what it says—the same all over. Gaussian produces a more speckled effect. If you’re adding noise to duplicate existing noise in a grainy photo, you probably want Gaussian distribution. For an old-newspaper-photo look, try Uniform.
Monochromatic. This setting limits you to grayscale noise. Take a look at the bottom-left image in Figure 13-6, and notice how many more colors you can see in the noise, compared to the solid green of the original. The bottom-left acorn’s noise was applied with the Monochromatic setting turned off.
Figure 13-6. Filters can really spruce up solid objects. Top: Here’s an unfiltered, solid green acorn drawn with the Shape tool (page 428). Bottom left: The same acorn after adding some uniform noise. Bottom right: Adding the Angled Strokes filter gives the acorn a lot more texture. (If you don’t add noise before applying this filter, nothing happens when you apply it.)
Noise can also help when you want to apply special effects to blocks of solid color, as shown in Figure 13-6. If you try to apply the Angled Strokes filter to a solid color, you don’t see the strokes. Adding noise first gives the filter something to work on. To make an abstract background for a project, you can create a blank file, add noise, and then run various filters on it.
Probably the most frequently used of the Blur filters, Gaussian Blur (Filter→Blur→Gaussian Blur) lets you control how much an image is, well, blurred. Besides using it on large areas, like the background in Figure 13-7, bottom, you can apply this filter at a very low setting to soften lines—useful when you’re going for a sketched effect. To try out the different blurs, download yellowbeak.jpg from this book’s Missing CD page at www.missingmanuals.com.
When using the Gaussian Blur, you have to set the radius, which controls how much the filter blurs things; a higher radius produces more blurring. Use the filter’s preview window to see what you’re doing.
Note
Elements 10 gives you two new ways to blur your photos, both of which are described in the box below.
Figure 13-7. Top: This little guy felt hidden enough to let the camera get pretty close, and he was almost right: It’s hard to focus on him with all the stuff in the background. Blurring the background will center the focus on the bird rather than the distracting details. Bottom: Applying the Gaussian Blur filter to the background makes the bird the clear focal point.
As you can see in Figure 13-8, the Radial Blur filter creates a sense of motion. It has two styles: Zoom, which is designed to create the effect of a camera zooming in, and Spin, which produces a circular effect around a center point you designate.
The Radial Blur dialog box looks complicated, but it’s really not. (Call it up by going to Filter→Blur→Radial Blur.) Unfortunately, Elements doesn’t give you a preview with this filter, because applying it requires so much processing power. But the dialog box gives you a choice between Draft, Good, and Best quality. You can use Draft for a quick look at roughly what you’ll get. Then, undo it and choose Good for the final version. (Good and Best aren’t very different except on large images, so don’t feel you have to choose Best for the final version. However, with an up-to-date computer, you probably don’t need to bother with Draft because your machine can whip up a final version a lot faster than computers could when this filter was first created.)
Figure 13-8. A Radial Blur applied in Spin mode. As you can see, this filter can produce an almost vertiginous sense of motion. If you don’t want to give people motion sickness, go easy on the Amount setting. A setting of 5 was used here, but unless you’re looking for a psychedelic ’60s effect, 1 or 2 is usually plenty.
After choosing your blur method (Zoom or Spin), adjust the Amount slider, which controls how intense a blur Elements applies. Next, click in the Blur Center box to tell Elements where you want the blur centered, as shown in Figure 13-9. Click OK when you’re finished.
If you’ve already given the Average Blur filter a whirl, you may be wondering what on earth Adobe was thinking when they created it. If you use it on a whole photo, the image disappears under a monochromatic soup, something like what you’d get by pureeing all the colors in the photo together.
Oddly enough, this effect makes this filter a great tool for getting rid of color casts (Removing Unwanted Color). You can use the Average Blur filter to create a sort of custom Photo Filter (Photo Filter) toned specially for the image you use it on. The secret is using blend modes (Blend Mode). Here’s how:
Open your image and make a duplicate layer.
Press Ctrl+J/⌘-J or go to Layer→Duplicate Layer.
Apply the Average Blur filter.
Make sure the duplicate layer is the active layer (click it in the Layers panel if it isn’t), and then go to Filter→Blur→Average. Your photo disappears under a layer of (probably) unpleasing solid color, but you’ll fix that next.
Change the blur layer’s blend mode.
In the Layers panel, set the Mode drop-down menu to Color. Already things are starting to look better.
Invert the blur layer.
Press Ctrl+I/⌘-I to invert the layer’s colors.
Reduce the blur layer’s opacity and do any other necessary tweaking.
Use the Layers panel’s opacity slider; start at 50 percent. By now, the color should look right—no more color cast. Tweak if necessary, and then save your work.
Tip
You may want to add a Hue/Saturation layer if you find that, no matter how you adjust the blur layer’s Opacity setting, the photo still looks a little flat.
The Average Blur filter is a particularly good way to color-correct underwater photos, where it’s hard to get a realistic white balance using your camera’s built-in settings.
The Surface Blur filter is yet another way to blur images. At this point you may be thinking that you already have enough ways to eliminate details in your photos, but Surface Blur is actually really handy, especially on pictures of people. This filter is smart enough to avoid blurring details and areas of high contrast, which makes it great for fixing skin. If you want to eliminate pores, for instance, or reduce the visibility of freckles, this is your tool. And it’s simple to use, too:
Open your image and make a duplicate layer.
Press Ctrl+J/⌘-J or go to Layer→Duplicate Layer.
Tip
For best results, start by selecting the area you want to blur (see Chapter 5 for help with selections). Then make your duplicate layer from the selection so you can keep the details in the areas you aren’t trying to fix. For example, select only the skin of your subject’s face, leaving out the mouth and eyes so they won’t be affected by the blur. Or, better yet, adjust the whole duplicate layer and then use a layer mask (Layer Masks) to mask out the areas where you want to keep the details, or just erase those areas.
Apply the Surface Blur filter.
Make sure your duplicate layer is the active layer (click it in the Layers panel if it isn’t), and then go to Filter→Blur→Surface Blur. If necessary, move the dialog box out of the way so you can watch what you’re doing in the main image window and in the dialog box’s preview area.
Tweak the filter’s settings till you like the effect.
The dialog box’s sliders are explained below. Be cautious—it doesn’t take much to make your photo look like a painting. Click OK when the flaws are concealed as much as possible without losing important details like eyelashes.
If you want, change the duplicate layer’s blend mode and/or opacity.
Use the Layers panel’s controls for this step. If you want to eliminate blemishes, for example, try the Lighten blend mode.
The Surface Blur filter isn’t hard to understand, but you usually have to do a fair amount of fiddling with its sliders to get the best balance between softening and preserving detail for a natural-looking effect. Here’s what the sliders do:
Radius. As with other filters, this setting controls how far Elements should blur your image. Move this slider to the left for a smaller blur, or to the right for a wider blur.
Threshold. This slider controls how different in tone the pixels have to be for Elements to blur them. A low setting means less blurring (fewer tones will be blurred); a higher setting means more blurring.
If you want to do a lot of experimenting, instead of dragging the sliders, try highlighting the number in each setting’s box and then using the up and down arrow keys to adjust the effect.