A normal lens, also called ‘sphere’, has an even convex shape. A downside to this is that it can cause a distortion of the image called spherical aberration: the parallel rays of light that come through the glass do not meet in the same exact focal point, with a faulty image as a result.
Giving the lens an a-spherical shape (such as a paraboloid, hyperboloid or ellipsoid), we can correct this unwanted side effect. That advantage is especially useful in zoom-lenses.
The production process of the a-spherical lens form is more complicated than that of the regular convex. That is why the prices of aspherical lenses are so much higher.
Is investing in an aspherical lens worth it?
We recommend choosing an aspheric lens to anyone that wants to achieve professional results as a photographer.
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