Understanding the Adaptive Wide Angle filter

In certain occasions you may find that Photoshop's lens correction filter or the respective Bridge features are not good enough in correcting the geometrical distortions associated with using wide-angle or fisheye lenses. The Adaptive Wide Angle filter, which was introduced in Photoshop CS6, can prove very useful & intuitive. Let's check how it works.

Click here to download the photo used in this tutorial:

Decompress the tutorial photo and load it in Photoshop.

Before editing the photo, do something simple yet fundamental to non-destructive editing: convert the background layer into a smart object: Go to the layers panel, right click the background layer and select "Convert to Smart Object". Photoshop will retain the original pixels into the smart object layer. All your edits with the Adaptive Wide Angle will be saved into a "smart filter" which you can double click any time and re-work your settings.

From the main menu select: Filter > Adaptive Wide Angle. The filter window shows up. 

Set the Correction mode to Perspective on the upper right window corner

At the top left corner you can see the filter tools that let you apply the so-called "constraints", or zoom and pan. You can use the two constaint tools to draw a line or a polygon respectively, in order to selectively straighten the distorted areas of your photo:

On the upper right of the filter window there are a number of settings associated with the way Photoshop applies the geometrical corrections. Photoshop will analyze the photo file and automatically select the best type of correction. The Auto mode usually works very well. Below these settings you can see a preview window that lets you place the constraints more accurately.

Click on the Constraint tool (the first tool at the top left) and draw a line from point A to point B.

This line is parallel to the the floor; in other words it is horizontal. Therefore we can assign the horizontal attribute to this constraint: right-click on the line and select "horizontal" from the flyout menu:

Now draw a horizontal line from point A to point B, as shown below:

Right-click on the line and select "horizontal" from the flyout menu.

The wooden columns look curved. Draw a line from point A to point B, the way shown below, to straighten the left column:

The column is vertical, therefore we need to assign the vertical attribute to this constraint. Right click on the line and select "Vertical" from the menu:

TIP: Holding down the Shift key while dragging will automatically assign the horizontal (or vertical) attribute to your constraint.

Now extend the constraint by clicking and dragging from point A to point B, to straighten the walls:

Repeat the same steps to straighten the other columns and the walls. If necessary click and rotate the marks on the circles to fine tune the constraints:

Click OK when finished.

Such distortion corrections create transparent areas along the edges of the photo. We can use the Content-Aware tools to fill these areas:

Select the Magic Wand Tool (press W). Hold down Shift and click inside each transparent area. 

Choose: Select > Modify > Expand from the main menu, enter 3 pixels and hit OK.

Press Shift and F5 to invoke the Fill menu. Click on "Use and select Content-Aware. Hit OK.

Press Ctrl-D (PC) or cmd-D (Mac) to deselect.

Here's a comparison of the photo before and after the Adaptive Wide Angle filter: