Typically, when I’m out shooting landscape photography or sunrise and sunset images, I always try Velvia out in-camera to see how the film simulation affects the image.
Velvia never fails to inject vibrancy, saturation, color, contrast, and brightness into an image. Check out the following image with Velvia.

So, the very same morning, the very same coastline and the very same camera, lens, and exposure with Eterna – see the difference below:

It can be challenging to describe in words the simulations that Fuji builds into their cameras or the impact of the film simulation on a given image, but it does pay off to know, or hold a mental model of the effects of film simulation because you can actually use it to impact the exposure and even influence the composition of the image.
The top image has more of a warm glow, and conjures association of glory, celebration, awesomeness, and inspiration.
The bottom image has more of a neutral, and slightly cooler tone, which makes the image appear more negative or, better put, less positive, than the top image. With the subject of the man in the lower photo, you can perceive a longing, a reflective state, perhaps even regret or sorrow, injected into the image from the film simulation (besides the subject).
In contrast, the subject of the camera looking toward the horizon, colored with Velvia, gives more of an uplifting, motivational, and optimistic tone.
Leave me a comment and let me know your thoughts – what’s your go-to film simulation and why?