According to Wikipedia (so it must be true), Iceland’s Dettifoss (pictured here) is reputed to be the most powerful waterfall in Europe. The numbers are impressive: 330 ft. wide with a 150 ft. vertical drop. Subjectively speaking, these waterfalls are big. But all these numbers and words don’t mean much without an element of scale in the picture, a known unit that can be compared to the waterfalls. This is where I come in, wearing a red jacket for effect and to add color, and raising my hands in a sort of victory pose while trying not to get blown into the drink.
I like to add an element of scale to an image when I know the viewer will not be familiar with the subject, such as Dettifoss. It is a visual cue to show how big (or small) the subject is. You can also use natural elements (like trees) or man-made objects (like a building or a car) for the same purpose, as long as it adds to the picture (here it adds a human element to the otherwise stark landscape).
To get this shot, I framed the waterfall to my liking and took a few pictures (if possible I take pictures of the same subject with and without people; you never know which one a magazine editor will prefer). I also made a mental note of where I should stand and walked down to the spot. I asked my wife to take some pictures after I gave her the thumbs-up from below, and presto. I used a tripod and locked in my settings so my wife would not have to fiddle with them.
Sometimes, especially if you are going for a more artistic rendition of a subject, you may not want to add an object for scale. You may want the viewer to be unsure of what the subject is, or how big it is (like a close up of a section of the waterfall, for example). That’s the whole point, to surprise and intrigue. And that’s OK too.
Now get out and shoot something.