Be sure your blacks are black

I've not had an issue with any of my Sticker Mule orders - ever! - but for one shirt I have now had a learning-experience. When I am putting a design on a black shirt, and elements of the design also have black (like a black border around the image), the team at Sticker Mule always magically 'blend' the black so that it disappears into the shirt. Again - if an image is surrounded by black on the image, it fades into the shirt instead of showing a black square "border" around the image. My fault I guess, but from the tiny thumbnail provided as a Proof, it was impossible to see that this border existed on the shirt. So a strong suggestion to ensure that your blacks are EXTRA black/dark, if in a similar situation to me. I might try to have the shirt reprinted in the future if I can figure out why the image printed this way.