I looked through the posts that came up with this title and a slight variation to it. This question remains.
Do you yourself change the format of an original photo, say a 6x4, when you add even width borders or drop shadows? Or do you keep the original format and get uneven borders?
For instance, if you want to keep the original 6x4 format and use even borders, say for printing on standard 6x4 paper, then the original image will have to be trimmed "narrower" than 6x4.
If you have a program that can add borders, what does it do? Odds, or evens?