maryavon09,
I began viewing a three part tutorial on youtube about making bottle cap images using Photoshop Elements. Here is the link to part one if you are interested:
http://www.youtube.com/watch?v=P2O_kr4UAZUAlthough she is using a different image editor program, her tutorial was done well enough that I was able to get a basic understanding of what she does. If the caps you make turn out fine, then feel free to disregard all of this.
First, she starts off with a 4"x6" image at 300 pixels per inch. Gimp's default is to set images at 72 pixels per inch. So, when you make a new image file, you will have to expand the Advanced Options in the New File Dialog window and set the Resolution to 300x300 pixels per inch.
She then copies/pastes an image into the 4"x6" image as a new layer.
She uses the Ellipse Select tool set to a size of 1.030 inches X 1.030 inches for her circle size. You indicated that you would use a value of 1 inch, and that ought to work since 1.030 inches is only very very slightly larger than 1 inch.
Anyhow, on a 4"x6" image, she gets 5 rows of three round images.
I don't know your familiarity with Gimp, but if you watch the video linked above and the other two parts of it, and you are reasonably familiar with Gimp, translating her instructions for use in Gimp is fairly easy. If you are a novice, then it could end up being confusing.
In any event, just adding the basic information that I was able to glean from the video tutorials in case it might help some. Looks like kind of a fun little project.
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