Photoshop features an intelligent mechanism to automatically reduce image blurring caused by camera motion. If necessary, you can adjust advanced settings to further sharpen the image. The Shake Reduction filter in the Filter > Sharpen menu can reduce blurring resulting from several types of camera motion; including linear motion, arc-shaped motion, rotational motion, and zigzag motion.
The camera shake reduction feature works best with decently lit still camera images having low noise. The following types of still images are particularly suitable for shake reduction:
- Indoor or outdoor images captured using a lens with a long focal length
- Indoor images of a static scene taken with a slow shutter speed and no flash
In addition, shake reduction can help sharpen blurred text in images affected by camera motion.
- Open the image.
- Select Filter > Sharpen > Shake Reduction. Photoshop automatically analyzes the region of the image best suited for shake reduction, determines the nature of the blur, and extrapolates the appropriate corrections to the entire image. The corrected image is displayed for your review in the Shake Reduction dialog.
The Detail loupe in the lower-right pane lets you closely examine the region in focus. If necessary, zoom in or zoom out on an image element. As you drag the Hand tool over the Detail loupe to examine an image region, release the mouse button to see a quick preview of the shake reduction changes for that region.
If no corrections seem to be applied to the image in the Shake Reduction dialog, ensure that the Preview option in the right pane is enabled.
A blur trace represents the shape and extent of the blur that affects a selected region of the image. Different regions of the image may have differently shaped blurs. Automatic camera shake reduction takes into account the blur trace for just the default region of the image that Photoshop has determined as most suitable for blur estimation. To further fine-tune the image, you can have Photoshop compute and consider blur traces for multiple regions.
Available blur traces are listed in the Advanced panel of the Shake Reduction dialog. You can click a blur trace to zoom in on it.
Photoshop provides several ways to create and modify blur traces. For best results, create blur traces in regions of the image that have edge contrast. For example, the region labeled A in the illustration below is better suited for blur estimation than the region labeled B.
You can simply resize the boundaries of the region in focus to update the associated blur trace. To shift focus to a different region, drag the center pin of the region currently in focus.
- Click the Add Suggested Blur Trace icon () in the Advanced panel in the right-pane. Photoshop highlights a new region of the image suitable for blur estimation and creates its blur trace.
- Add more blur traces if necessary.
Click the trash can icon () to delete one or more selected blur traces.
- Click the Blur Estimation Tool icon () in the upper-left corner of the Shake Reduction dialog.
- Draw a selection rectangle anywhere on the image. Photoshop automatically creates a blur trace for the region you selected.
- Add more blur traces if necessary.
- Select the Blur Direction Tool () from the left panel.
- Draw a straight line representing the blur direction on the image.
- Using the Detail loupe, focus on a new image region suitable for camera shake reduction.
- Click the Enhance At Loupe Location icon () to move focus in the left-pane to the region highlighted in the Detail loupe. The blur trace for the region displayed earlier in the Detail loupe is automatically updated.
The keyboard shortcut Q lets you dock/undock the Detail loupe.
Once you've added the required blur traces, you can select one or more blur traces in the Advanced panel to apply them to the image.
- With the Ctrl key (Windows) or the Command key (Mac) held down, select the blur traces in the Advanced panel. Photoshop displays the multiple preview pane for the selected blur traces.
- Drag a blur trace onto the Add Suggested Blur Trace icon ().
Photoshop creates a copy of the blur trace and locks the duplicate copy.
Once you've created blur traces; you can save them, so that they can be applied to different images.
- Select one or more blur traces.
- Select Save Blur Trace from the Advanced panel flyout menu. You can save blur traces in two formats—KNL and PNG.
When you want to reuse the saved blur traces for a different image, you can use the Load option in the Advanced panel flyout menu.
The Blur Trace Bounds setting represents the bound size of the blur trace. You can adjust this value if necessary.
Photoshop automatically estimates the amount of noise in the image. If necessary, select a different value (Auto/Low/Medium/High).
Smoothing reduces high-frequency sharpening noise. You can move the slider to a value different from the default 30%. A low Smoothing setting is recommended.
Sometimes, in the course of sharpening the image, you may observe some noticeable noise artifacts. Follow these steps to suppress these artifacts:
- Select Artifact Suppression.
When Artifact Suppression is not turned on, Photoshop generates coarse previews. Coarse previews are sharper, but they also have more noise artifacts.
- Adjust the Artifact Suppression slider to a higher value. 100% artifact suppression yields the original image, while 0% artifact suppression does not suppress any noise artifacts.
Artifact suppression works best to suppress medium-frequency noise.