Still working this out, but seems to work. I was having problems printing copies of designs for my cane handles. Often best I could come up with was 2" difference. Ran across this by accident - distance is the answer it would seem.
The trick is, distance from the camera. Closer, or further, from the camera, when moved to my computer, and print, give different sizes. Print one that was taken an inch further from the camera, and it will be a tad smaller than the one that was taken an inch closer. And they seem to be clear.
When I can get the time, have a long cardboard box, about 8" wide, 3 or 4" deep, and about 48" long. This will be marked at 1/2" intervals for the whole distance. Then fix the camera to one end. A stand for the design to be photographed, and start taking shots at 1/2" intervals. This may be more close than needed, but won't know until I try it. Important to know the distance each picture was taken at, so you can duplicate it at any time. From what I have figured out so far should be able to get the photo sized to about 1/8" of what the final design wanted. And, for me, that's close enough. Pretty sure I could get it closer if need be, but I think 1/8" would wind up close enough.
This is going to take a lot of photos, a lot of printing, a lot of comparing, and figuring out how to tell the distance each photo was taken at - I'm thinking maybe hooking a number on the paper, and change every time you move it.
"It ain't what you're told, it's what you know." - Granny Weatherwax
Some days, the supply of available curse words is insufficient to meet my demands.
Call me a craftsman, artisan, or artistic, and I will accept that. Call me an artist and you will likely get a quite rude comment in return. I am not a @#$%ing artist.