Any filter applied to a Smart Object is a Smart Filter. Smart Filters appear in the Layers panel below the Smart Object layer to which they are applied. Because you can adjust, remove, or hide Smart Filters, they are nondestructive.
You can apply any Photoshop filter (that has been enabled to work with Smart Filters)—except for Lens Blur, Flame Picture Frame, Trees, and Vanishing Point—as a Smart Filter. In addition, you can apply Shadow/Highlight as Smart Filters.
To work with Smart Filters, select a Smart Object layer, choose a filter, and then set filter options. After you apply a Smart Filter, you can adjust, reorder, or delete it.
To expand or collapse the view of Smart Filters, click the triangle next to the Smart Filter icon, displayed to the right of the Smart Object layer in the Layers panel. (This technique also shows or hides Layer Style.) Or, choose Layers panel Options from the Layers panel menu, then select Expand New Effects in the dialog box.
Use filter masks to selectively mask Smart Filter effects.
To apply a Smart Filter to an entire Smart Object layer, select the layer in the Layers panel.
To constrain the effects of the Smart Filter to a selected area of a Smart Object layer, make a selection.
To apply a Smart Filter to a regular layer, select the layer, and choose Filter > Convert For Smart Filters, and click OK.
Choose a filter from the Filter menu. You can choose any filter, including third-party filters that support Smart Filters, except Extract, Liquify, Pattern Maker, and Vanishing Point.
Choose Image > Adjustments > Shadows/Highlight.
If you apply one or more filters using the Filter Gallery, they appear as a group in the Layers panel named “Filter Gallery.” You can edit individual filters by double-clicking a Filter Gallery entry.
The Smart Filter appears under the Smart Filters line in the Layers panel beneath the Smart Object layer. If you see a warning icon next to a Smart Filter in the Layers panel, the filter doesn’t support the image’s color mode or depth.
After you apply a Smart Filter, you can drag it (or an entire group of Smart Filters) onto another Smart Object layer in the Layers panel; press Alt-drag (Windows) or Option-drag (Mac OS) Smart Filters. You can’t drag Smart Filters onto regular layers.
If a Smart Filter contains editable settings, you can edit it at any time. You can also edit blending options for Smart Filters.
When you edit a Smart Filter, you can’t preview filters stacked above it. After you finish editing the Smart Filter, Photoshop again displays the filters stacked above it.
Editing Smart Filter blending options is similar to using the Fade command when applying a filter to a traditional layer.
To hide a single Smart Filter, click the eye icon next to the Smart Filter in the Layers panel. To show the Smart Filter, click in the column again.
To hide all Smart Filters applied to a Smart Object layer, click the eye icon next to the Smart Filters line in the Layers panel. To show the Smart Filters, click in the column again.
You can reorder Smart Filters in the Layers panel, duplicate them, or delete Smart Filters if you no longer want to apply them to a Smart Object.
Photoshop applies Smart Filters from the bottom up.
To duplicate all Smart Filters, Alt-drag (Windows) or Option-drag (Mac OS) the Smart Filters icon that appears next to the Smart Object layer.
When you apply a Smart Filter to a Smart Object, Photoshop displays an empty (white) mask thumbnail on the Smart Filters line in the Layers panel under the Smart Object. By default, this mask shows the entire filter effect. (If you made a selection before applying the Smart Filter, Photoshop displays the appropriate mask instead of an empty mask on the Smart Filters line in the Layers panel.)
Use filter masks to selectively mask Smart Filters. When you mask Smart Filters, the masking applies to all Smart Filters—you can’t mask individual Smart Filters.
Filter masks work much like layer masks, and you can use many of the same techniques with them. Like layer masks, filter masks are stored as alpha channels in the Channels panel, and you can load their boundaries as a selection.
Like layer masks, you can paint on a filter mask. Areas of the filter that you paint in black are hidden; areas you paint in white are visible; and areas you paint in shades of gray appear in various levels of transparency.
Use the controls in the Masks panel to change the filter mask density, add feathering to the edges of the mask, or invert the mask.
By default, layer masks are linked to regular layers or Smart Object layers. When you move the layer mask or the layer using the Move tool, they move as a unit.
A border appears around the mask thumbnail.
To hide portions of the filter, paint the mask with black.
To show portions of the filter, paint the mask with white.
To make the filter partially visible, paint the mask with gray.
You can also apply image adjustments and filters to filter masks.
In the Masks panel, drag the Density slider to adjust the mask opacity, and the Feathering slider to apply feathering to the mask edges. See Adjust mask opacity or edges.
The Mask Edge option is not available for filter masks.
Shift-click the filter mask thumbnail in the Layers panel.
Click the filter mask thumbnail in the Layers panel, then click the Disable/Enable Mask button in the Masks panel.
Choose Layer > Smart Filter > Disable Filter Mask.
A red X appears over the filter mask thumbnail when the mask is disabled, and the Smart Filter appears without masking. To re-enable the mask, Shift-click the Smart Filter mask thumbnail again.
If you delete a filter mask, you can subsequently add another mask.