Have you heard of blue prints? In the past, professionals such as engineers, architects, and drafters commonly referred to the duplicates of the original drawings as “blueprints” or “floor plans.” This terminology arose because photocopiers had not been invented at that time. Therefore, cyanotype printing played a crucial role in duplicating copies of the master document. Essentially, it functioned as a method for replicating documents manually before the advent of photocopiers.

Cyanotype printing, which was unveiled in 1842 by Sir John Herschel, a polymath with expertise in chemistry, experimental photography, mathematics, and astronomy, was achieved by blending Ferric Ammonium Citrate and Potassium Ferricyanide. This discovery marked a significant milestone because the mixture is responsive to Ultraviolet Light, commonly referred to as sunlight.

This technique is recognized as an alternative photographic printing process and is often called sun-printing. Nevertheless, it remains relatively unfamiliar, particularly in Singapore.