What is this?

Tips and tricks on how to use BM241-BT label printer, and general thermal printer use.

Printing in grayscale vs color

Linux handles colors differently if they print in grayscale vs if they print in color when passing it off to the label printer.

Printing in grayscale allows for dithering to be set up, whereas printing in color without any prep work gives you unreadable prints with blown-out tones. Understanding the CUPS print stack and what changes an image goes through before being printed would be beneficial here.

Darkness setting

Darkness seems to affect the image very little, if at all. Printing from darkness 0 to 15 produces negligible differences. Have not tested with different print speeds.

Print speed

Print speed has much more effect on the image, with fast print speeds yielding lighter images and slower print speeds yielding darker images. Need to do more testing to see what looks better.

File format

Different file formats may yield different results. Unsure how to get SVG printing going.

TODO

• Try setting up a color range test to get a better idea of what colors will look like; make a print test image with grayscale squares from 0% to 100%, incrementing in 5% steps, then document how the colors come out.
• Using the data collected above, create a consistent print pipeline that yields similar results to what's seen on the screen, so that edits can be made with less guesswork and wasted labels.