This is almost certainly a printer issue, not a Photoshop issue.
Most printers in the "no borders" mode enlarge the image slightly and overspray beyond the edges of the print to make sure that it prints borderless with no white border showing. It is to cover any variances in paper size, alignment in the paper path, etc..
If you want absolutely perfect sizing and cropping on the print, your best bet is to print on larger paper without the borderless option and then trim.
While I’ve never printed borderless it seems to me that the ink sprayed beyond the edge of the paper has to go somewhere. Doesn’t that cause problems with the paper rollers?
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While I’ve never printed borderless it seems to me that the ink sprayed beyond the edge of the paper has to go somewhere. Doesn’t that cause problems with the paper rollers?
It can if the printer is not designed well and/or the user is printing a large number of borderless prints. Normally the printer has a tray and/or wick underneath the printhead path that catches the overshoot. Also, this area is normally between the rollers so they are located outside of the overspray area.
Thanks a lot guys, I remember now about the overspray. I’ve always used QImage for printing in the past. It has a ‘disable overspray’ option which solves this problem, and literally what you see on screen is what you get on paper.
Does CS4 have an option for this somewhere?
it seems to me that the ink sprayed beyond the edge of the paper has to go somewhere. Doesn’t that cause problems with the paper rollers?
Printers that will have this problem generally force a margin on the user. As Dennis says, a few printers allow borderless printing by … what he said.
Does CS4 have an option for this somewhere?
Not that I’m aware of. You could, however, try creating an action that would expand the canvas by a fraction of an inch in each direction and experiment with that.
It is also worth checking carefully all of the options within the print driver of your printer. Some printers have options for reducing or eliminating the borderless overspray (I think Epson refers to it as "Expansion" on some of its printers). Many don’t.
QImage is also an alternative as you mention.
What you need to do is select "borderless" or "no margins" and then scale down a bit so as to overcome the automatic enlarging. Experiment starting at 96% or so. You might want to create an image consisting of rectangles at 1px, 20px, 50px in from the borders of the image (@ 300 ppi), where the image is sized identically to the paper, and see how close you can get to the proper reproduction.
Good suggestions, guys. Thanks.