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What is a photo lens?
It can be a separate part of the camera, or directly integrated into the shooting system, as on cell phones. It defines the angle of view and the focusing distance. It will enlarge or reduce the image you perceive to freeze it on a defined frame.
A lens is characterized by its focal length, i.e. its magnification and angle of view. The longer the focal length, the greater the magnification and the smaller the angle of view. Conversely, the shorter the focal length, the lower the magnification and the wider the angle of view.
Nowadays, most smartphones come with several lenses that allow you to shoot from 20 mm to 100 mm cleanly.
50 mm lens
This is largely standard, as this focal length is considered to be close to the perception of the human eye. Basically, with a 50 mm lens, the captured photo is faithful to what you actually see. In the case of fishing, it's an ideal lens for taking pictures of fish while respecting their proportions.
It's a versatile lens that can also be used for atmospheric shots.
Wide-angle lens
Focal lengths are generally between 15 and 30 mm. As mentioned above, the magnification is low, but the angle is wide. It's an ideal lens for taking pictures of fish that are rather distorted, with an assertive style. It highlights the fish and makes it appear larger.
This type of lens is very useful for landscape photography.
Fisheye lens
This is a very wide-angle lens that distorts the image considerably at focal lengths of less than 15 mm. Its purpose is to take rather artistic photos, or to capture a fish by integrating all the surrounding environment. This lens can also be used for "half-air, half-water" photos, in which the fish, its environment and the angler are immortalized in the same image.
Long focal length lens
We're talking about lenses between 100 and 600 mm or more. These are heavy, cumbersome lenses. These are focal lengths that aren't found on phones, or at least don't allow for quality rendering on smartphones.
This type of lens is ideal for atmospheric or wildlife photos of fishing. They provide high magnification.
Macro lens
This is an interesting type of lens for capturing small details. Most of these are 100mm lenses, which can be used to magnify miniature elements.
It is possible to make this type of image using a diopter, which often fits 50 mm lenses. All you need to do is find a diopter with a diameter compatible with your lens.
