Working for many years as a designer and art director, I have experience creating a variety of collateral: identity campaigns, branding, email, books, newsletters, packaging, and posters . . . amongst other things.
I use Photoshop on everything from nearly invisible photo touch-up and color correction to creating complex and magical photo illustrations. Using this skill I'm currently one of the top-selling designers at SelfPubBookCovers, the world's leading resource for pre-made book covers.
Even though I started as a traditional pen & ink illustrator, I now use the computer to either finish my work or as the primary drawing tool. So after some quick sketches, I can finish the piece and have it "print-ready" faster than any deadline.