neat stuff from the biggest nerds of all time.
Here the nerds are trying to explain how to look at their pictures:
For a Gigapxl™ print to be perspectively correct from a viewing distance of 10 inches (the distance at which close-up inspection is performed), its 9"×18" format must be enlarged to 10.5×21 inches. At this size, the linear pixel density of a 1000-megapixel print is approximately 84 pixels/mm. During an earlier discussion of digital prints for which pixelation causes negligible loss of sharpness, we noted that this condition requires each megapixel of information to occupy an area no larger than eight square inches; the corresponding linear pixel density being 13.9 pixels/mm. Consequently, to fully assimilate the information contained in a 10.5×21-inch Gigapxl™ print, the viewer requires a binocular microscope having a power which is given by: 6.0×(84/13.9)