Its no surprise that there is quite a bit of misunderstanding out there about aperture and it’s impact on overall lens quality.  Let me say that aperture and lens quality are not “directly” linked.  Lenses are much more complex than that.  Here are some questions to ask yourself when selecting a lens.  What will I be shooting with this lens?  How much available light do I usually work in?  What is my shooting style and/or the style of my shoot (these can be very different).

I should only speak from the perspective of a portrait / fashion photographer here so I’ll try to stick to that.  It’s quite often that I see someone photographing people with an f-stop of 1.2 or greater and it’s all too often that the tip of the subject’s nose is in focus but the rest of the face quickly drops out-of-focus.  But I paid all that money for a lens with a huge aperture, why not use it?  For one thing, don’t just buy a lens for it’s large aperture.  Don’t overlook the glass!!!!!  What really makes a lens great?  Great glass and great build quality.  This is a highly arguable issue but in my opinion Leica makes “The Finest Optics In The World“.  It’s only behind Leica that Carl Zeiss and others fall into suit with great glass and build quality.

How do I pick an aperture?

I love a creamy background as much as any portrait photographer however I also love when the subject is in focus.  I’m not discouraging anyone from purchasing lenses boasting apertures of 0.95 – 1.4 and so on if you shoot in low light situations.  I just want to make sure that everyone knows that shallow depth of field is attainable with lenses that have a max aperture of f4.  For example the image to the left was taken with a Leitz Leica 90mm Elmarit, stopped down to f4 in natural light.  With some companies, the only way to get your hands on their best glass is to purchase their premier lens which only has the option of a large aperture.  For arguments sake lets take two lenses that will give you an option.  Let’s look at Canon 70-200mm f2.8L versus their 70-200mm f4L.  If you only shoot in bright daylight and hence don’t really need the faster f2.8, the f4 will give you a pleasing image if you simply place a bit more room between your subject and the background (not to mention saving you quite a bit of money).

Bokeh

What the heck is bokeh you might ask?  A lens renders out-of-focus highlights as small translucent spheres.  Look at the roses in the bushes behind the little boy in the image above.  Aperture has a direct impact on the shape and smoothness of these little highlights.  Typically the more aperture blades and the curvature of those blades will determine whether the bokeh will be pentagonal, hexagonal, or the most desired smooth and round.  Do your research when picking out a lens.  If beautiful bokeh is what you are looking for find a lens that has an aperture that will be able to deliver regardless of size.

Moral of the story

My goal with this article is to as simply as possible explain that you can get a fantastic lens without purchasing the largest aperture available.  For me, when I’m photographing people, I rarely ever use anything larger than f2.8 and am usually shooting between f4 to f8.  For fashion work you may even want to stop down to f11 or more.  The paramount issue when selecting a lens should be the quality of the glass and build quality of the lens itself.  Aperture is of relative importance to the type of shooting that you are doing.  Shape and construction of the aperture may in many cases be much more important than the size.  I personally shoot predominantly Leica but also Hasselblad by Carl Zeiss, Mamiya, and Canon lenses.  Check back soon for an article on formats.  I shoot both medium format and full frame and I’ll discuss the difference.  Please feel free to start up a conversation or ask questions…

Leica Handcrafted Lenses  Here is a beautiful little video of a Leica lens being born.