I was surfing posts on GIS stack exchange, as one does, when I came across this post featuring a French textbook figure on cartographic visual constraints. It’s a handy little reference piece on minimum point sizes, gap widths, line widths, area differentiation thresholds, and so on, so I translated it to English to share with you here.
I’m not by any means a French speaker so if you see any problems with the translation please let me know and I will fix the graphic. (Edited 12/10/15 as per Bennett’s comment below.) I’ve left the commas instead of replacing them with periods, due entirely to laziness and my faith in your intellectual agility.
Visual thresholds for cartographic features https://t.co/7SXFTaU4S3
— Gretchen Peterson (@PetersonGIS) December 4, 2015
#1 by Steve Bennett on December 5, 2015 - 5:50 pm
The last two translations in the column on the right seem a bit off. I think they should be:
“The difference in thickness of lines near each other needs to be at least 0.1mm”
“The difference in thickness of distant lines needs to be at least 0.3mm”.
(Hard to express succinctly!)