Greyscale in Doodle Scan

Last night I was reading this excellent post about scanning pencil artwork and the first step the artist mentioned is setting the pallette to greyscale. This made me realise how useful that would be on Doodle Scan — the black and white mode is good but only in some circumstances where the drawing is just lines, greyscale would be much more useful for illustrations with colour or shading. Like all the other features on Doodle Scan, it wasn't immediately obvious to me how to do this. After some digging and experimenting with changing RGB values, I realised the relative luminance value I use to check for if the colour is light or dark can be rounded with Math.round to get the value I need. So 253.123 becomes 253 and I set the RGB value of that pixel to 253,253,253. Below are examples of the three colour modes with default settings from Doodle Scan and if you want a drawing a bit like this or anything you want really you can donate to St Jude. Colour version Greyscale version Black and…