Why would the coloring from a canvas tent rub off on whatever touches it – clothes dog skin?
Most canvas tents are older tents. If you have a newly manufactured tent that is made out of canvas then it may not be a high quality tent. Newer tents are made out of nylon and other man made materials. the colors are on the material before it is made. It sounds like your tent was dyed after the material was woven. The best thing I can tell you is to wash the tent and rinse it well. This may get out whatever colors that want to come out, out.