Quote Originally Posted by ann View Post
It isn't you doing anything wrong. 35mm negatives do not fit the ratio of a piece of 8x10 paper. You can print 6x9 and it will fit, but not with the standard borders.

When you changed focal lengths you also change the relative distance between the negative and the paper, so success.
that would be a 'qualified success' though, cause you will have cropped some off the ends to get the vertical (assuming printing landscape orientation) to fit... which based on OP's reply needs to be emphasised. So to repeat Ann's 1st reply, 35mm will not enlarge to 8x10 without cropping. Print it 6x9 and it will fit on 8x10 paper with uneven borders.