print size and borders

Our standard borders for each print size are as follows : 
(Please refer to photos below)
4 x 6   -   1/2 inch
4.5 x 6   -   1/2 inch  
5 x 5   -   1/2 inch
5 x 7   -   1/2 inch
6 x 9   -   1/2 inch
8 x 10   -   3/4 inch
11 x 14   -   1 inch     
13 x 19   -   1 1/2 inch
16 x 20   -   1 1/2 inch
16 x 24   -   1 1/2 inch
17 x 22   -   1 1/2 inch

 
 

Our floated border allows for a photo to retain the same aspect ratio, but would yield a border that is thicker on the short sides of the photo and narrower on the long sides. The image would be uncropped.