What is the hardest part of preparing photos for laser engraving?

I’m curious to hear from laser users and makers:

What part of image preparation causes you the most trouble before engraving?

For example:

- removing backgrounds

- improving low-quality photos

- choosing the right dithering method

- preparing images for wood or metal

- creating clean vectors or line art

- getting consistent results from photo engravings

I built PixGrav around these exact problems, so I’d really value hearing what other users struggle with most.

What is the one part of your workflow you would most like to make easier?