I've written an in-depth article on my full resolution printing technique, published by PetaPixel, that includes some instructions for preparing files. If you are printing your own photos, you should give this a try, and of course I offer printing with this technique. I continue to be in awe of the quality of print this technique produces.
900 ppi prints?!?! That’s kinda crazy, right? You just need to print at 300 or 240 or 200 because some guy on the internet told me no one can tell the difference. But it works, and it works really well! I'm going to be talking more about this, but for now, check out this video I made to explain it.