Artists keep still for ages thus making themselves perfect targets for other artists and creating a balanced economy of supply and demand.
I failed horribly to draw Mary while she painted, but next day I made nice Prisma variations of a sketch of a Prisma variation of a photo of the scene.
Here’s the process, first the photo:
Next, the Prisma version of the Photo:
Now the actual drawing, 5m with 6B:
Now the drawings with Prisma filters, further tinted using Google Snapseed:
Finally, my father asked what his watercolours would look like after the Prisma treatment. Here’s the result. To my surprise he though they’d make great greetings cards.