The nebula gets its name from its resemblence to a character in the popular video game. But in this image, the Pacman does not look all that Pacman-like to me. It's rotated wrong and is sort of a bit over done.

In my original version of this nebula seen below, it does look more like the video game character. It is also more colorful but not quite as bright or large.

The primary difference between the two images is the hydrogen-alpha filter (Ha) used on the above picture. The Ha filter does a much better job of capturing faint details that are often missed in regular optical light images like the one below on the left. The other difference is that the photo above was taken with a longer focal length telescope. This magnified the nebula by over twice as much and so it appears considerably larger.