Lens Elements and Groups


Today’s Question: As I was looking up the number of aperture blades on my lenses, I saw a specification that made me wonder: Do the number of lens elements and number of groups have any effect on bokeh, starburst or other aesthetics?

Tim’s Quick Answer: The “simple” answer here would be that no, the number of lens elements or groups of elements wouldn’t have an impact on the creative aesthetic effects produced by a lens. Of course, the real answer is far from simple.

More Detail: There are a variety of factors that impact how many individual lens elements are included within a camera lens. However, aesthetic factors such as the bokeh or starburst effect would not be significantly impacted by the number of lens elements or groups.

What we call a “lens” in photography is actually a piece of sophisticated equipment that includes multiple lens elements. As a very general rule, better image quality and greater light transmission is achieved with fewer lens elements. However, that’s not to say that fewer lens elements will translate to a better lens.

More lens elements are also required to correct for distortion in a lens. In this respect, more lens elements can mean that the overall image quality will be improved, at least in terms of distortion. These types of corrections will often involve pairs of lens elements, which form an individual group of elements. So you can get some sense of the degree of correction being applied within the lens by the number of groups.

However, while the generalizations above may often be true, they are not accurate across the board and therefore can’t be used reliably to make a decision about lens quality or aesthetic results. In other words, I would generally recommend ignoring the number of lens elements and groups, and instead focus on other methods of determining the results you can achieve with a lens, such as reviews the delve into details such as the resolving power of the lens.