Unfortunately I do not know the names of the artists, but will mention them if I find out. I think this one is signed "Campix" or "Camix". But what a marvelous way to use a boring wall of this type, which I saw in several places during my visit in Thessaloniki last week. I will use a couple of them in my little "photography school" here.

Phototip 6 of 100 - Show the size ratio

When you want to show how large or powerful something is, you should always remember to bring a small detail along with the larger object. A classic example is to bring a box of matches in an image of things on a table, such as freshly caught fish or craft items. You can use the same principle when you eg composes a view image. A person, as here, is often effective. So: look for something of known size to bring to the viewer of your images to understand the size ratio. And when it comes to people, you just need to anticipate a little where someone goes, and wait until the person is in the right place in the image.