I've worked on various retouching gigs for UniWorld Group, Inc., the longest-standing, full-service, multicultural marketing and advertising agency in the United States. Here's one that Involved a rather large social media (Instagram) and print campaign for their client, Ford.
There were over 30 different images. The work involved creating files that could work in social and in print ads. I had to alter the images (retouching, composting, color) and then get them to resemble the deeply saturated colors and contrast of Instagram filters.