litlwing13

I am a photographer, and have recently been looking into turning some of my photos into fabrics. In order to do this, I need to create a seamless image that will repeat without harsh edges. There is a tutorial for doing this in Illustrator or Photoshop, which applies an Offset filter, and then allows a change in the horizontal and/or vertical pixel count, to allow for a wrap around effect, where any four blocks will create a complete image. I have been experimenting, but am not having any luck so far. I am just wondering if I am missing something easy, or if it is something I need to request as an addition in a future update. 
 
Thanks
 
PS. Just in case I am not explaining it well: https://support.spoonflower.com/hc/en-us/articles/204482270-How-To-Create-A-Seamless-Repeat-For-Spoonflower-Using-Adobe-Illustrator-Photoshop