Summary - Photonsters/MaskMappingTools GitHub Wiki

Some LCD-based resin printers have uneven light distribution across the screen, due to the way the LED light source is placed underneath, manufacturer's design of the LED array, etc. Some firmwares for these printers have a function that allows you to define a mask that slightly dims the brighter areas of the screen in order to give a more uniform illumination and hopefully enable more consistent dimensional accuracy across the build plate. You can also attempt to construct an analog mask that you would physically place between the LCD and resin vat.

Leveling your LCD brightness could be done in a few steps:

1. Divide your LCD into a grid and measure the brightness as accurately as possible at all points in the grid.
2. Convert that grid of intensity data into a series of corrective values to fix uneven illumination
3. Create and install a mask from those corrective values.
4. Re-measure the grid to see how well the corrections work.