We have a vague idea of what Roman emperors may have looked like with the help of ancient stone busts made centuries ago. Now, Canadian designer Daniel Voshart has taken it one step further by creating colourised, photorealistic portraits of 54 rulers from The Principate. It began as a quarantine project for Voshart, who primarily works with Virtual Reality (VR) for the film industry. He was able to make the portraits with the help of historical references, Photoshop and a tool called Artbreeder, which uses machine learning to create composite images. This means that the tool can combine two images or more seamlessly, borrowing elements from each to put the final version together. Voshart’s process made use of 800 images of busts, which he transformed or restored to make them as accurate as possible, in order to create the 54 portraits of the emperors. The work involved a great deal of research, as the designer cross-referenced the emperors' appearances, such as hair, eyes and ethnicity, to historical texts and coinage. He then tweaked the images in Photoshop accordingly. Over the course of the project, he has changed features based on additional information he came across. In one example, he points out the Roman emperor Macrinus, who, in some busts was depicted with a narrow nose, but coinage suggests that he may have had more North African features due to Amazigh origins. In many instances, Voshart has noticed a pattern of what he calls “whitewashing” certain emperors, who have been rendered with more European features in busts and coins. He gives examples such as Septimius Severus, who was born in what is now Libya, and Caracalla, his son. When it comes to skin tone, he notes that some choices, though reached after an amount of research, are still speculative. “Assigning skin texture where no information is available has been unexpectedly controversial. I want to be absolutely clear this is an artistic interpretation – an educated guess based on birthplaces and UV skin map. Art, not science,” he wrote on Twitter. Indeed he has used a bit of creative license in other portraits, adding images of celebrities into the Artbreeder tool in order to make the countenances more realistic and human-like. In other cases, he would use his own judgment, with the help of a bit of historical information, to decide on the final look. "My goal was not to romanticise emperors or make them seem heroic. In choosing bust and sculptures, my approach was to favour the bust that was made when the emperor was alive. Otherwise, I favoured the bust made with the greatest craftsmanship and where the emperor was stereotypically uglier — my pet theory being that artists were likely trying to flatter their subjects," he said in a <a href="https://medium.com/@voshart/photoreal-roman-emperor-project-236be7f06c8f">blog post</a> about the project. Voshart sees educational value in his work, and he has released smaller versions of his images on Creative Commons for the public. He has also sold limited-edition prints of his work to support the project.