Here I am measuring the paper to figure out the borders of the paper so there is even spacing around the exposed area. The paper measured at 12"x8". I was printing two images, one 35mm and one square format, so I would need to figure out the border for the square in the middle of the 12x8 sheet too. For 35mm frames I wanted an even 1 inch border which meant the final image size measured at 10"x6" and for square prints the image size would be 6"x6" in the middle of the paper.
I had to use up one piece of paper to measure the borders, this piece could not be coated in liquid light and used as a print once the writing was on it as this could cause the ink to run in the chemicals and contaminate the whole process. So this pape is just for measurements.