After scanning a page, I always make one print version in high resolution and one low-res online version. This time, I was in such a hurry (trying to teach myself a new schedule: 5 days of work, 2 days of drawing comics) that I saved the latter as the former, and there was no way back. I had to re-scan everything and redo the greyscales (eventually… or I can leave myself a nice surprise for the day when I’ve finished the whole chapter, just about to put together the print version).