I do not believe that in photography there are absolute rules of composition, but it is undeniable that certain compositions work better than others.
Why? Probably because our brain is the result of millions of years of evolution, and as in two dots and a line we recognize a face (you don’t believe me? Have a look here), in the same way we recognize some images as more pleasant to look at than others.
So let’s look at a few tricks to keep in mind during your next visit to the seaside.
Start following rules
Before trying to break rules, try to follow them. Start with the Rule of Thirds: divide your image into nine equal parts by two equally spaced horizontal lines and two equally spaced vertical lines. Then place important compositional elements along these lines or their intersections. The result will be that your photo becomes more balanced. In a seascape shot, for example, try to put a Lighthouse on one of the vertical lines and the horizon on one of the horizontal ones.


Choose the leading actor
If you follow the Rule of Thirds, you’ll never again put the horizon in the middle of your image, and that’s a great thing unless you have a perfectly symmetrical reflection.
In the image below, the rock formation in the foreground is really interesting with this tide and so I decided to emphasize it giving to the sky just 1/3 of the image.


Choose the leading actor
If you follow the Rule of Thirds, you’ll never again put the horizon in the middle of your image, and that’s a great thing unless you have a perfectly symmetrical reflection.
In the image below, the rock formation in the foreground is really interesting with this tide and so I decided to emphasize it giving to the sky just 1/3 of the image.


Use leading lines
An image is like a book, and to really enjoy it you should be able to read it from the begin to the end. To do that, try to use lines and curves to guide the eyes through a path. You can use a road or the natural line of the coast for example. Keep in mind that you should avoid interrupting that path because it’s like skipping a line in a book: you lose the sense of the story that you’re telling. Also, try to avoid lines that guide the eyes of the reader outside the image. You want attention given to what is inside the image, not to what is outside.


Avoid straight objects in the margin
One common problem of wide angle lenses is the perspective distortion when the camera is not aligned perpendicularly to the subject. In other words, buildings like lighthouses appear to be falling if you (correctly) place one according to the rule of thirds. Well, the bad news is that there is no a universal solution. The best one is obviously to buy a lens with excellent optical quality, but they are very expensive and in any case the perfect lens does not exist. So we need to correct the distortion in post-production. There are a thousand ways to do that, but most of them require an image crop. For that reason, if you have a straight object in your frame, don’t put it exactly on a vertical line of the Rule of Thirds, but slightly closer to the image center. In that way, after correcting the distortion, your lighthouse will be nearer the vertical line of the third.
In the image below (that it’s another good example of leading lines) if I had put the small village too close to the frame edge, it would be affected by perspective distortion and to correct it in post production probably I would have lost the nice leading line with a crop.


Add dimension and scale
When I started taking seascape pictures, I was a purist: no humans or human artifacts were allowed inside my frame. If humans are still not allowed to join, sometimes I think it’s a good idea to put some artifacts in my composition. The main reason is that even if you exactly the dimensions of the rock formations in front of you, viewers of your image may have no idea if they have never visited that place. When you look at an image, your brain tries immediately to define the dimensions comparing the unknown to something known..help it and use something like a lighthouse, bridge, church to give an idea of scale. A reef is even more beautiful if it is perceived as high and massive.
In the image below, the lighthouse gives a dimension to the other rocks in the image (try to cover the lighthouse with your finger.)


Use the negative space
I’m a big fan of using negative space. But what exactly is that? Easy: it is nothing but the space around, and between, the subject of an image. Yes, basically they are “the” nothing. So, how can that be useful? Negative space is perfect to emphasize the subject. A lonely church on the top of a cliff is even braver if it seems that it challenges the vastness of the sea.
In the image below, the old church reminded me a solitary sentinel who scrutinizes the sea, and so I decided to emphasize it using the negative space.


Have fun
Finally, remember that every rule is made to be broken. If the horizon is not perfectly in one third because the sky lacks of clouds, put it above the upper horizontal line of the rule of thirds. If you need to put a lighthouse near the margin of the frame to use leading lines, just do it.
The real goal of a picture is not to follow the rules, but to arouse emotions in the viewer. Keep this in mind and there is no composition that can overcome you.
Here below the lighthouse is on the right vertical line of the rule of thirds. Unfortunately, I didn’t have a wider lens with me and I had to put it there in order to use leading lines in the foreground and not to cut the nice wave trails in the upper left side of the image.