Glad to hear it works for you, Nick.
I wonder at what distance the phones can read the image?
You're right on distance making a difference. I read where a large one on the side of a building or trailer could require a distance of 65 feet to read.
As far as smaller items, be careful when sizing the code down. My friend's phone wouldn't read the tiny QR code he tested on a pamphlet. The pamphlet didn't end up with a code taking up the page, but there are limits and ratios (found on the web). The lesson learned was always test the image.
