How to Apply Photoshop Blur Filter

Use Photoshop to select one of a multitude of blur effects.

Photoshop blur filters soften either an area of a photograph you have selected, or an entire image. They smooth transitions by averaging the pixels next to the hard edges of defined lines and shaded areas in the image, creating a soft effect. Apply these filters to an entire image or to single layers within a multi-layered photograph depending on your needs.

Instructions

Basic Filters

1. To apply a Blur Filter, open an image in Photoshop. Go to the Filter Menu at the top of your workspace and select "Blur."

2. Select “Average” for the filter to find the average color of the image or selection in the image and then fill in the area with that color to create a smooth look.

3. Choose “Blur” or “Blur More” for the filter to remove any noise where a significant color transitions occurs. The Blur filter smooths the transition, and “Blur More” produces the same effect at about three times the strength of just “Blur.”

4. Select the “Gaussian Blur” to blur a selection with an adjustable amount. The pop-up window provides you with a Radius sliding tool to choose the amount of blurring that works for the image.

5. Choose "Box Blur" to create a blur that uses the average color value defined by the neighboring pixels, which is especially helpful when blurring special effects. Adjust the calculation by changing the the size of the area; a larger radius creates a greater blur effect.

Lens Blur

1. Select the "Filter Menu," then "Blur," and then "Lens Blur." Adding this type of blur to the image produces a depth of field-type effect, where some objects in the image stay in focus and others areas become blurred.

2. Choose “Faster” under the Preview option to make your previews quicker, or “More Accurate” to see the final version of the image.

3. Choose the source from the Depth Map in the Source pop-up menu. Drag the "Blur Focal Distance" slider to set the depth at which the pixels are in focus.

4. Select “Invert” to invert the selection or alpha channel you're using as the depth map source.

5. Choose an Iris shape from the Shape pop-up menu. Drag the "Rotation" slider to rotate the iris, and to add more blur, drag the Radius slider. Adjust the sliders on each effect to the left or right to see what effects they produce. Click the "OK" button when you are done making changes.

Other Blur Choices

1. Choose "Motion Blur" to create a blur effect in a particular direction and at a specific intensity. The effect is comparable to taking a picture of a moving object, like a car, when you have a fixed exposure time.

2. Select "Radial Blur" to create a blur that is similar to a camera zooming in or out. Play with the controls of this feature, by adjusting the amount of blur (from 1 to 100) and with the different types of radial blurring: spin or zoom, and with the quality; draft, good or best.

3. Choose "Smart Blur" for an effect that very precisely blurs an image. Specify the radius, which determines how wide an area the pixels is blurred, and the threshold, which determines the type of pixels to blur, based on their similarity to other pixels. Then set a quality; normal, low or high, and a mode; normal, edge only or overlay edge.

4. Choose "Surface Blur" to blur the image, but keep the edges sharp. Use the Radius option to set the area that is blurred in the image. Use the Threshold option to to control the pixel tones of the pixels near the center of the blurred area. Photoshop excludes pixels that vary less in tonal value than the tonal value of the defined threshold.

Tips & Warnings

• Play around with the effects and save copies for your own reference and later comparison.

References

• Adobe Photoshop CS5: Blur Filters

Resources

• Read this Article in Spanish