I have a Canon Pro-10 printer. It is known that in the printer settings if you set the Media Type to a fine art paper then the driver enforces a 30mm margin on the print. So if you try to print from Lightroom but have 10mm margins it refuses to print until you change something.
Now I can get around this by setting the Media type to a photo paper so I could print edge to edge on a fine art paper.
My question is;
As I can set the paper size in the Page Setup dialog, I have colour managed by Lightroom and I use the correct ICC profile for the paper/printer, does this Media Type setting actually do anything in respect of the print? I have printed some canvas prints and I can see no difference in the print quality?
It looks like the only difference in the Fine Art Media Type setting is the forced 30mm border margin. Apparently there's a potential to curl at the edges if you print borderless on Fine Art paper. As long as you're using a Media Type setting for a similar paper type it should work fine as you've experienced. Just make sure you are using the proper Fine Art paper profile in LR's Print> Print Job> Color Management.