QR code tests. I used a more real world test template. A title with x and y coordinates to identify the approx position in the home. I test different sizes , focal points , lighting ect. I did a short video demonstrating the best results so far.

Here is the second largest QR code at 6ft with illumination with a medium sized QR code. I tested the standard QR code in ez builder and I could only get it to reliably read at 2 -2.5ft with optimal illumination. The largest code seems large in the.picture but once it is on the ceiling it doesn't look that big. Adjusting gridlines I found I could narrow the box to just above the size of the QR code and it wouldn't read a QR code nearby that was not in the gridlines. However if more that half of a QR code is in the box it will try to read it so QR codes should be spaced 50 percent of their physical width apart to keep from having confusion.