Correcting Sloping Horizons
Leaning Pictures

'Squaring-Up' the Image

Clive R. Haynes FRPS

As often happens a photograph is not square, either the horizon slopes or the verticals lean (not converge - that's a separate issue - see 'Converging Verticals' link below).

The image above would make a reasonable landscape picture if the severe slope to the left could be fixed.

A sloping or leaning picture is quickly corrected in Photoshop and this is what you do.

Decide what part of the image needs to be either properly horizontal of vertical and will act as a reference.

Select the 'Measure Tool.'

In P'shop 6 & 7 it's part of the 'Eyedropper' tool set (above the 'magnifying glass' tool).

In P'shop 5 / 5.5 it's on the tool bar above the 'Paintbucket' tool.

Left: Where to find the 'Measure' tool in P'shop V6 & V7
Draw a line on the image across the place you need to level up. (In the next move, the image will be rotated to make this line precisely horizontal or vertical - whichever).
In the example below the 'line' was made along a wall above the far shoreline.
A white line on the image below shows the location.
Go to Image > Rotate Canvas, choose 'Arbitrary' .
The next 'box', shown below, will indicate the amount of rotation needed and a choice of direction - either CW (ClockWise) or CCW (Counter ClockWise)
Click on the appropriate direction.
Click 'OK'.
When the image has been rotated, use to 'Crop Tool' to remove the excess from the edges of the picture.
And -"Bingo!" - There you are!
Know-How Contents
Converging Verticals
e-mail CRHfoto