What are you hiding by not showing us the upper right corner of the images?
The strange, stair-shaped images come from the Wide Field and Planetary Camera 2, or WFPC2. WFPC2 consists of four cameras, each of which takes a picture of a section of the target. It's like taking four pictures of a single scene, then putting them together to create the whole picture.
But one of WFPC2's cameras takes a magnified view of the section it's observing, to allow us to study that section in finer detail. When the images are processed, that magnified section is shrunk down to the same size as the other sections, so that it fits into the image.
For a more thorough explanation for the stair-stepped shape of the Hubble photos, visit our Web site.
Read Hubble's Wacky Window on HubbleSite.