11-22-2017, 08:05 AM
Because when you copy/paste the image in Paint, you paste just the pixels and not the intended print definition. Paint prints the image with its own default print definition (and in addition MS software often has its own very special understanding of what you want to do...). Things could be different (note conditional), if you export as JPEG/PNG from Gimp and reload from file in Paint (which would then perhaps check the print definition stored in the file).