Optical Print Centering
| 1/16 | 1/8 | 3/16 | 1/4 | 5/16 | 3/8 | 7/16 | 1/2 | 9/16 | 5/8 | 11/16 | 3/4 | 13/16 | 7/8 | 15/16 |
| .0625 | .125 | .1875 | .25 | .3125 | .375 | .4375 | .5 | .5625 | .625 | .6875 | .75 | .8125 | .875 | .9375 |
Use the same units for each dimension; fractions are optional.
Include the space between the mat and print edges if appropriate; print size and distance from the top will still refer to the print itself.
If you are really picky, reduce the mount dimensions by the part covered by a frame. (You will have to add this to the distance from the top of the mount.)
If the top margin is narrower than the sides after optical centering, consider either making them equal, or if the bottom is then narrower than the top, vertically centering the print. “Correct narrow margins” will do this automatically.
You may also choose a different centering mode.