A well-chosen picture explains the content of your blog post at once. A photograph can show something that otherwise would need a lot of words in a single image.
Sometimes it is better to crop a photo to get the focus on the desired part. I will show you what rules there are when you crop a picture.
Cropping is considered making alterations to a picture. When you use photographs that somebody else made, make sure you have permission to change them.
Continuation of guidelines for cropping: Have a look at this article for the first five guidelines.
6. Straight horizon
Is there a horizon in the picture?
A horizon in the photo is either consciously in an angle or straight. If it is a little bit crooked, the readers of your blog will think it is a mistake. Put it straight with programs like Photoshop or Gimp.
7. Look at more than just the main subject
Are there ugly shadows or remaining patches after cropping?
Compare these pictures with each other. In the one below a little part of the leg and a funny shadow are visible. With a different crop those ugly pieces are gone, making the image better and more interesting.
8. Direction of lines
An obvious start of a line in the corner
A carpenter always says, “If it fits, it won’t fit”, so he will never choose for a line to start right in the corner. It depends on the technique what you have to do. If you are not the one finishing the design (e.g. in printing, where someone else does the formatting), then you better not let a line begin exactly in the corner, because it’s bound to come out differently than you intended.
9. What’s the story?
The crop can contribute to what you want to say
In one picture you can see a woman at the tide line. In the other picture you can see a threatening sky and a different composition. Which one expresses “loneliness”?
10. Think outside the box
Why should a frame always be square
Have a look at comic books. A lot of times the subject peaks outside the cadre.
I love these kinds of images!