When I print first I select paper size and then the option to print borderless. Then I get two more options: 1 is to print borderless - retain size and the other is to print borderless - auto expand. (I'm using an Epson printer and this may be unique to that maker). I have tried it both ways and don't see any difference, but there must be something.
Does Anybody know?
Auto expand enlarges the image slightly so that a few pixels around the edges may be off the printed paper. Retain size does not enlarge the image, but may cause a thin white border on one or more edges of the paper depending on the alignment tolerances of the paper as it feeds through the printer. The white line may also appear if the aspect ratio of the image is not exactly the same as the aspect ratio of the cut paper.