We often take photos and for whatever reason don't quite align them right so the horizon is straight. In this shot of Emma Quintin at Barrow Hill Roundhouse Railway Centre I was concentrating on getting the right pose and I didn't quite get the camera horizontal. As there's no clear horizon with a straight line you may not notice, but if you look at the fence on the left it's sloping in slightly. Sometimes this happens when shooting with wide angle lenses, but the clue that this is not the case here is that the railway carriage on the other side is sloping in the same direction. If a wide angle had been used that would be sloping in to the left.
In Lightroom the crop tool combines as a handy rotational tool and you can rotate the image by as little or as much as you like.
With the photo open click on the Develop tab at the top and select the square crop frame in the right hand panel. This places a frame around the large centre photo.
KEY TIP: The R key selects the crop tool. The X key does a quick central crop and then alternates between a horizontal or vertical crop.
You can then click and hold anywhere on the frame to move it. Clicking on the top or bottom lets you crop and reduce the height, while clicking and dragging left or right lets you crop from the sides. If you click in a corner you drag the frame and crop horizontal and vertical at the same time.
If you move the mouse cursor slightly away from the edge of the photo you will see the cursor icon change to a rotating tool. Now if you hold down the mouse you can rotate clockwise or anti-clockwise by moving the mouse up, down, left or right. While rotating the cropping adjusts automatically to avoid out of photo areas appearing.
To ensure the photo is totally aligned horizontally I drag one of the frame edges in, left or right to check vertical alignment or top or bottom to check horizontal alignment, and position it a part of the image that I know should be correctly aligned as a reference point. So in the example below I used the metal fence post and then I rotate until the frame edge is parallel with the post. Then I can move the frame back out for a suitable crop.
KEY TIP: Hold the shift key down when pulling in any edge of the frame to maintain the photo's proportions. Or if you always want to keep the aspect ratio click the padlock icon in the tool menu to the right so it appears locked.
You can, if you prefer, set a fixed aspect ratio by clicking on the word original next to the padlock to show the pop up box with a series of preset aspect ratios, such as widescreen 16:9 and standard 4:3.
One I have the correct alignment - and everything is perfectly upright I readjust the crop for the desired composition.
Below left is the original, and on the right is the slightly tighter crop with a subtle amount of straightening of the uprights.
KEY TIP: The O key charges the overaly guide to help you crop and compose a better photo using standard compositional subject placement. The defaul is Grid but you also have access to the following overlays: Grid, Triangles, Rule of Thirds, Golden Ratio, Diagonals and Golden Spiral (also more commonly known as Golden Mean).