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The Angles

One of the most common nuisances I’ve come across in photography has been the witnessing of un-straightened lines. Horizon lines, Building faces, roofs, fences, and other architectural elements which should have 180 degree horizontal or vertical lines, have been captured at some odd perspective and made to look somehow, off. Unless you’re doing something purposeful with these off kilt angles, try to become aware of this nuisance, and of the method to fix it.
Take this simple example :

Before (top) After(bottom)

In the before image, my lapse in attention during image capture led to a maladjusted horizontal in the image.
A simple adjustment using Lightrooms’ crop tool , or the straighten tool in the ” Tuning” panel of Picasa can easily fix this.
You will lose part of your image with this adjustment, however, the sacrifice- if you have a subject well placed away from the edges- will not harm the work. I lost part of a light fixture in the upper left corner, and some ceiling on both sides, no harm.

Next up,

Contrast