Converting these pics into a PDF question

[quocko]

hey all, i've been pretty much keeping all the HQ MTG pix on my iPhone as CBR files so i can view them on the go. works great but i'm trying to phase out CBR files on my phone in favor of iBooks, the problem comes when i try to "combine supported files in acrobat"

i'll try to be more clear. most of the sets work flawlessly but there are a few like Antiquities and Arabian Nights(others too)that do not convert into PDF properly even though the file dimensions are the same(480x680)

i added a few examples. notice the white borders on the Amulet of Kroog scan. when viewing as a JPG in the HQ releases they are not present however they are there when you combine them as a PDF. the Mirrodin Besieged pic is beautiful border to border.

if someone can explain what's going on i would definately be a happier person