Straightening Horizons & Verticals - Part 2
When you tilt the camera upwards to get the top of a building into the shot, you end up with converging verticals. The more you tilt the camera the more the verticals will converge. The effect can be quite dramatic and pleasing when it is done on purpose, sometimes though you will want to straighten them up.
Start by dragging some guides from the rulers onto the picture and placing them at critical positions so you can see when the verticals are correct. Just place your cursor on one of the rulers, the side if you want a vertical guide and the top of you want a horizontal one, click and drag onto the picture and you will see a blue line as in the picture below. These are 'non printing' guides, they will not appear on a print or a saved copy of the file, they are only visible in Photoshop. If you can't see rulers at the edge of your image, go to the 'view' menu and switch them on.
Next go to the layers palette and duplicate the background layer. You should always work on a duplicate layer whatever you are doing so you can always go back to the original. Also the 'transform' effect which we are going to use won't work on the background layer.
Make sure that your new duplicate layer is the active layer and select edit -> transform -> distort. As you can see there are several choices on the transform sub-menu, distort is the 'free form', 'anything goes' (almost) choice.
You need to click the 'maximize' button in the top right corner of the picture window so that you can see what happens outside the picture area.
You will see a marquee around the picture that can be dragged any way you want.
Below I have pulled out the top corners to the left and right, mainly on the right, to correct my verticals.
You will find that as you pull one side it affects the other side so you need to go back and forth moving the handles bit by bit.
Finally I pulled the top up a bit to make the building slightly taller to compensate for the fact that the top is now a little wider.
Press enter and you're done. The guides will only show in Photoshop but, if you want to get rid of them go to the view menu and click 'clear guides'.
So now there is no excuse for tilting horizons or converging verticals in your pictures, unless they are there for dramatic effect.
If you are a Facebook user, follow this link to my 
If you enjoyed this page you might
be interested in my eBook
Learn Photography with Geoff Lawrence
Other tutorials in this section
Introduction page.
Scaling your files.
Balancing those pixels.
A short video showing how to use the levels adjustment to control contrast.
A short video showing how to use the curves adjustment to control contrast.
Dealing with color casts.
An introduction to Adobe Camera RAW.
Advanced use of Adobe Camera RAW.
Using the unsharp mask.
Masking parts of your picture to edit certain areas.
How to build accurate layer masks.
A must for landscape and building photographers.
Using layers in Photoshop.
How to make a better job of changing images from color to black & white.
Playing with contrast and tones to give a more dramatic effect.
How to shoot and process HDR pictures with Photomatix Pro software.
Video Tutorials
A short video showing how to resize your images for the web.
A short video showing how to make color corrections.
A short video showing how to use the levels adjustment to control contrast.
A short video showing how to use the curves adjustment to control contrast.
A short video showing how to use the Quick Mask mode to select areas of your photo.
A short video showing how to blend two layers together using a clipping mask to remove unwanted parts of the image.
A video demonstrating how to use the sliders in ACR
A video demonstrating how to use the tools in ACR
A video explanation of non-destructive editing.