User talk:AndyE

cracked it.

it works in 16 bit, not 8 so it needs to be something like

gm convert -type grayscale -colors 256 -operator ALL AND 32768 -threshold 32767 (infile) (outfile)_8
gm convert -type grayscale -colors 256 -operator ALL AND 16384 -threshold 16383 (infile) (outfile)_7
gm convert -type grayscale -colors 256 -operator ALL AND 8192 -threshold 8191 (infile) (outfile)_6
gm convert -type grayscale -colors 256 -operator ALL AND 4096 -threshold 4095 (infile) (outfile)_5
gm convert -type grayscale -colors 256 -operator ALL AND 2048 -threshold 2047 (infile) (outfile)_4
gm convert -type grayscale -colors 256 -operator ALL AND 1024 -threshold 1023 (infile) (outfile)_3
gm convert -type grayscale -colors 256 -operator ALL AND 512 -threshold  511 (infile) (outfile)_2
gm convert -type grayscale -colors 256 -operator ALL AND 256 -threshold 255 (infile) (outfile)_1

Then the 8 files layered on top of each other in the cutter software with halving engrave depths on each one

Currently the script takes a percentage to use for the AND, then subtracts 1% for the threshold, it would provide better results at the low bit depths if it subtracted 0.1% or even 0.01% Anything less than the exact same number should work.

That said, even as is it seems to work pretty darn well. Original

Result ater rebuilding in GIMP

If we wanted to get the same resolution we'd need to pick out 256 shades of grey to laser, or better still hack the laser software to allow us to control the burn strength per pixel.