Fix lens distortion
The easiest way to fix lens distortion is to use the Lens Correction filter in Photoshop. If you’ve shot in raw, then once your image is open in Photoshop’s Camera Raw area, click on the small lens icon (6th tab in line). If you’re editing a JPEG image, you will find the Lens Correction filter under the Filter menu.
By adjusting the Distortion slider, you can correct the flaw made by the lens. You can also adjust the Vertical and Horizontal sliders to ensure your image appears straight in the frame. You may need to crop into the scene slightly if you’ve had to correct lots of distortion.