Realism Tutorial in Photoshop

Here is a realism illustration tutorial that you can apply in Photoshop. I've been looking for tips for my personal work, so here a tutorial if you're looking for one. This is what the author had to say about this tutorial, "it is a tutorial for how to cg or color realistically."

Click here to view.

Turquoise by Diego Fernandez

What is amazing about this illustration is that everything was created in Photoshop. I asked him if he drew this and then brought it into the computer, soon I found out I was wrong. This piece is so simple, but eye catching. The color makes it pop the most, but I find it inspiring when he told me, "It was made completely with photoshop, the lines and the color."I thought that was great. I find that inspiring, because it takes illustration to another level. I'm still messing around with the linework in Photoshop and find creating vector art in Illustrator easier, but works like this makes me want to continue practicing. The sketch feel makes this such an authentic feel, plus I like that their are certain spots on the skin like the face, where it looks as though it is stained by accident. What do you think about this piece?

Here is a previous post on another illustration of Diego Fernandez's