Printing in LR4, have custom paper for 16x24, select retain size option as per manual instructions. However, in the print module of LR4, the cell size is 15.75x23.44. I am unable to reduce the border sliders to 0. What am I missing here?

PRJ

Lightroom doesn't know how to print borderless on custom paper sizes due to the necessary image expansion.

Thank you cwebster, that answers that, will print from PS.

Thanks!