An ultra-wide angle (UWA) lens has a small focal length (usually less than 24mm) compared to that of the human eye (approximately 50mm). The focal length determines its angle of view: the longer the focal lens, the less you’ll see in the picture.
Being one of the most difficult types of lenses to use, it can become a great creative tool to exaggerate size and depth in a photo if used correctly.
An UWA lens is very useful for architectural and landscape photography where the photographer is not able to move far back from the scene to photograph. And of course, for real estate advertisements, it is the best kind of lens to use as a property looks MUCH larger than what it really is: you’ll quickly pay back that expensive lens with those property sales 😉
For me there are three main features that make this kind of lens great and unique:
– The ability to get really close to the subject, allowing me to use of flashes and other lighting devices.
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David is Michelangelo’s masterpiece from the Renaissance period (early 16th century). In this photo I was REALLY close to David’s feet, but still I was able to shoot all his body and that amazing ceiling (yes – that circular window is indeed the ceiling).
– Perspective of the image: objects near the lens appear massive and vast while far away objects seem tiny and near the horizon. A good composition should include in the foreground a subject that will be the main focus of the image, so that the viewer is not overwhelmed by many details.
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In the picture above, I used an UWA for a night landscape of Florence and Brunelleschi’s Dome looks many kilometres away whereas in fact it is not that far (you can compare with the pictures from my previous post Sunset in Florence).
– Convergence of vertical lines: even a small change in the composition will cause parallel vertical lines to converge (this happens in every kind of lens but is far more noticeable with UWA lens).
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For example in this photo, I was pointing the camera upwards and this resulted in all vertical lines of the scene to converge somewhere in the sky.
One last advice is to beware using this lens with people as their face and especially the nose will look very disproportionate in comparison to the rest of the body. In general, the shorter the focal length, the more distortion you’ll get.
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To sum up, with an UWA lens you can get really close to the subject, the perspective is exaggerated and parallel vertical lines become convergent. This is certainly my favourite type of lens and I’m sure you’ll have great fun once you get your hands on one!