How To High Pass Filter Photoshop

by

The High Pass filter is one of the many powerful features of Adobe Photoshop, which has been the leading tool for digital image manipulation in the industry. This tutorial will help you understand and utilize the High Pass filter to improve your images.

What is a High Pass Filter?

Before we jump into the how-to, it’s essential to understand what a high pass filter is. Named after its function in signal processing, the High Pass filter in Photoshop is used to allow high-frequency detail to ‘pass’ through while reducing the visibility of low-frequency, or ‘softer’, areas in an image. This method is often used for enhancing contrast and sharpness in an image.

How to Apply a High Pass Filter

To apply a High Pass filter to your image in Photoshop, follow these steps:

Step 1: Duplicate the Original Layer

Firstly, you need to duplicate the layer of the image you wish to apply the filter. It’s essential as we don’t want to permanently alter the original image. To duplicate the layer, you can use the Ctrl+J (Command+J for Mac) shortcut.

Step 2: Apply the High Pass Filter

With the new layer selected, navigate to the Filter menu at the top of the screen. From there, select Other, then High Pass. This will bring up a dialog box allowing you to control the radius of the filter.

// Pseudo Code
Filter: {
    select Other: {
        select High Pass: {
            set radius
        }
    }
}

Step 3: Adjust the Radius

The Radius control will determine the amount of detail to preserve. Setting it too low will result in not enough detail being preserved, while setting it too high will produce a halo effect around the details. A good starting point is around 2.0 pixels for high-resolution images.

Step 4: Change the Blend Mode

After applying the High Pass filter, you’ll notice your image now appears grey. Don’t worry; this is expected. The final step is to change the blend mode of the layer to Overlay. This will hide the grey tones and allow the high pass details to shine through.

// Pseudo Code
Layer: {
    select blend mode: {
        set to Overlay
    }
}

Conclusion

And there you have it! You’ve successfully applied a High Pass filter to your image in Photoshop. By experimenting with this technique, you can add more depth and detail to your images, giving them that professional edge. Happy editing!