I am getting back into training. I am doing the Bert Monroy "Pixel Playgroud" weekly photoshop projects. They are short 10 minute exercises that show you photoshop tricks for creating anything you want all from photoshop. I was very impressed with the commercial illustrations course from Bert and his ability to break down photoshop down to a simple program that requires exploring to learn what tools do, and understanding shapes, colors, and values.
Bert was kind to share a small fragment of a photoshop composition. In this section below, you see a group of clams.
Next Bert shared several clams created all in photoshop to show you how they can all come together to created a photo realistic composition. ( click on image to enlarge). Using only the 6 clams on top, Bert was able to created and entire composition position the clams in different places, at different perspectives while adding some extra shadows and lights to help created the realism.
Here are the clams i created, i will admit, they need some work. These are muddy clams. I did follow all of the steps as i followed along. I think these clams required a bit of experimenting with the tools for them to look the way Bert makes them.