I am hiding visually encrypted images in double layered lace. For more information on the process, go to this page).
- Use the python script (described on the page linked to above) on the image you want
Make sure the output images can be scaled up enough so you can add a grid on top
- Draw a rectangular grid on top of the two output images in Illustrator (click and hold the Line Segment tool and select the Rectangular Grid tool)
The amount of lines needed is the start size of the output images (amount of pixels horizontally and vertically) minus 1
- Export as PDF to get a clear export (all other options become blurry)
- Make a bitmap of the PDF in Photoshop (threshold 50%)
- Set the lasercutter to engrave but make sure that the laser actually cuts through the material by decreasing the speed and/or increasing the power