You can select : [u]download file[/u] instead of [u]send to my email account[/u] before you click [u]get file for offline use[/u] button ,  to solve this problem.
You can edit the content after you click the button, click [u]submit[/u] button again , and file can be downloaded to your computer (just select file folder and save it directly.).
It is the same for all the simulations at this web site.

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For a small pin hole, the sharp image is formed(pinhole1.png).

For a larger hole, it is a combination of several small pin holde.Each pin hole will form a sharp image, but those images will overlap each other. The result is not as sharp as a small pin hole(pinhole2.png).

For a verr large hole, the image become similar to the shape of the hole ((pinhole3.png)).