The "Standard" is Not Always The "Normal" - The overlooked 50mm lens

Why mention this? Well, simple really. It’s the decline of the 50mm prime lens’ popularity that causes us to miss its significance and deprive ourselves of a generally outstanding optic. The 50mm focal length definitely lost popularity in favour of that handy "standard zoom"; the aprox. 35mm to 70mm and it was easy to see why. Many of us even tolerated the relatively poor optical performance of some of these zoom lenses favouring their obvious convenience.

This change occurred principally in the SLR category, while those who remained committed to the rangefinder (Leica M being the most notable) obviously enough could not use zooms on their cameras to entice them away from the "normal" or “standard” lens. The 50mm focal length was safe in the hands of rangefinder users, although that camera category was to go into serious decline at the hands of Japanese SLR camera's fast growing popularity.

It was when I took up 135 format rangefinder photography some years ago (Leica M7) that I rediscovered the joys of the mostly forgotten 50mm lens.

The 50mm lens was popular enough among camera makers and their optical departments because it was the simplest focal length to design well enabling an easier mix of optical aberration design trade-offs. Although a fact of optical physics is that the perfect lens does not exist - all things are relative – the 50mm is often as close to perfect as possible. The designers' challenge is to (given various constraints set such as cost, size etc) achieve the highest degree of correction for each aberration and in doing so accept some trade-offs as one's correction leads to an adverse affect upon another aberration. Hence, quality lens manufacturers' best performing lenses are typically their 50mm lens.

So, that smallish not so sexy 50mm lens buried deep in your gadget bag might be the very best performing lens you won - by a long shot.

However, much more was lost with the 50mm's declining popularity at the hands of "normal" zooms - one of the finest optical instruments available in the 135 format (especially those offered by the premium optical companies like Nikon and Olympus) - arguably creative skills certainly took something of a back-seat ride too - we didn't have to think so much about image framing, nor use our feet so much either because that zoom would do that for us, or so we think.

My view is that the 50mm lens is one of the loveliest and most underrated focal lengths available in the "small" format - film and digital - the 50mm lens, which is neither simply "normal" nor "standard".

As photographers lusted for the growing number of zoom lens options and the convenience of infrequent lens changing despite these lens' limited (if not down right poor in many cases) optical performance. But, their personal image making skill development may have suffered as a result.

Although I personally feel that there is something quite lovely about that angle of view in any format; for my personal use I even prefer the well forgotten focal length of 40mm - that little bit wider and offering a more forgiving depth of field.

My purpose here is twofold:
1. promote a revival of the 50mm as an outstanding cornerstone of any photographer’s kit; and in the absence of selecting another focal length as your “normal” lens,
2, seriously consider it as your “normal” lens and gain the benefits of having a personal “normal” lens.

And what would those benefits be? A better understanding of one’s way of seeing the image they plan to make; of understanding how other focal length lenses you use (or plan to buy) fit around that focal length within that important context of understanding how we “see what we are seeing”.

What’s normal?

Contrary to what you may read, 50mm is NOT necessarily a "normal" lens; nor is a “normal” lens always defined by the lens’ angle of view (AOV) as equalling the human eye's "normal vision".

The commonly accepted definition of a normal angle of view is: that focal length in mm which closely approximates the diagonal length of the format's film frame in mm.

Certainly our general or peripheral vision is not as narrow as that of a 50mm lens. It falls somewhere between 28mm and 35mm. Even our narrower focused vision is more like that of a 35 to 45mm lens, but hardly a 50mm lens' angle of view.

I am also reminded by an enthusiastic reader of this article that there is another not-so-often mentioned reason for the term "normal" lens - it's to do with print viewing angle.

So to quote Ronald Jore: "...a reason why lenses with a focal length similar to the frame's diagonal size are called "normal" is that if/when the resulting print is viewed from a viewing distance equal to the print's diagonal size (as is considered "normal" by many), this results in a natural perspective, i.e. the perspective when viewing the print is the same as it would be if you stood at the point the photo was taken from and viewed the original scene."

He goes on to say: "I am not sure how accurate the assumption of "viewing distance equals image diagonal" is, but then there's always a simplification in every rule of thumb".

The image below taken at the Summer Palace's lake outside Beijing, was taken with a Canon EF 24-70mm f2.8L lens at about the 50mm point - it is such a natural perspective. Interestingly when I use that lens, I often find I shoot at about the 50mm mark!



Additionally, "normal" cannot really be defined by its focal length measure equalling the diagonal of the film image frame. Here, 50mm is not equal to 43mm (the 135 format frame diagonal length). That would make a 40mm more of a "normal" lens for such cameras.

Nor do these two popular definitions of a “normal” lens highlight the significance of a “normal” lens to an amateur photographer. It is well accepted that the smartest idea in buying a camera for a child who is keen to take photos is one with a single prime lens for obvious reasons of skills development.

But it’s certainly important to understand that what is "normal" for me may be quite "abnormal" for you.

But it is very worth while for a photographer to understand how he sees what he sees and what is the focal length by which he normally views the world. A famous Australian photojournalist exclusively uses a 21mm Leica-M lens in 100% of all his photography. That is his normal lens - it is how he sees what he sees.

My contention is that a 50mm 135 format lens is not necessarily “the” normal lens for every photographer and that a “normal” lens may in fact be any of a number of focal lengths. Equally, my contention is that determining and understanding what your own “normal” lens is can be a significant benefit – to how you shoot and also very important to how you build a lens kit. Of course, I’m not suggesting that your chosen “normal” lens be used exclusively.

These commonly given reasons for determining what the focal length of a “normal” lens risk misleading photographers about useful and often overlooked benefits of determining what their own “normal” lens focal length is.

It is the lens one selects to best match the way he generally “sees what he is seeing” – what does that mean? Simply, how we normally see images before us. It provides us with the right AOV; visual boundaries and optical perspective (or look) in a “normal” or typical photographic situation. It is a window that is completely comfortable - not too narrow and not too wide. It is the window where the main elements in view sit comfortably with a balanced perspective and showing no "extremes" like an abnormally deep foreground or abnormally compressed two dimensional background.

In even simpler terms, its the prime lens you'd feel comfortable with if you could have no other.

It is that one lens that matches our individual “normal” way of looking at a subject within an overall context that allows him to capture the image he wishes to convey - the subject and some explanatory environment.

Some photographers prefer to see such normal images in a wider perspective, while others prefer to see the same in a tighter perspective. Others simply like to match their eyesight in what they see as a “natural” perspective.

As a starting point if we consider the human eye’s natural AOV as a basis of defining a “normal” lens, we should note that a 50mm 135 format lens AOV of 45 degrees is narrower than the human eye typically sees. We have both "focused vision” and “peripheral vision". We see what we are concentrating on ahead of us as well as some degree wider to the periphery. We see "what we are seeing" within that wider view/context through our focused interest in that specific subject. If you are in doubt about this, sit back and think about what you are “seeing” as you look ahead in front of you.

Equally, the diagonal of 135 format film (24mm x 26mm) is about 43mm and not 50mm. More relevantly, this diagonal measure indicates the relative ease at which a lens designer may produce a highly accurate optical performance at a relatively low cost - that much is well known. But, how this measure helps a photographer determines to be his “normal” lens remains a mystery except that there may be a sense of balance to an image of such a diagonal equivalent focal length. I feel that such an aspect is more of an after effect - appeal of the taken image, rather than any measure of how we might "normally" see images before the event of taking the image!



Your “normal” view:

So, what is a 135 format normal lens? The answer is simple. It isn’t necessarily any one focal length. A “normal” lens is a matter of personal vision and photographic preference – how an individual photographer “normally” sees his subject within its overall context. This may vary among formats. He may elect to make the image with another AOV from another focal length, but this view is his “normal” view and is obtained from the one focal length that provides that view for him.

What ever that specific focal length is for you, the “normal” lens is important and that importance is often overlooked.

Why is my “normal” lens so significant?

Why is deciding on your own “normal” lens important to amateur photographers? The “normal” lens will ideally be the cornerstone of one’s lens outfit regardless of how many lenses one owns or even if all others are zooms – it’s the lens that helps determine the focal length of others in a well planned lens kit; it sets a balance among the various focal lengths one owns; it establishes a point from which wider and longer focal lengths are selected to compliment that “normal” way one typically shoots or generally likes to work (the way one normally sees what he is seeing). Specifically, it’s our “normal” lens that aids our choice among how much wider or how much shorter we want to take an image.



Under the practical circumstances of shooting images at a location, it is worth beginning to “see” and survey the location through his “normal” lens. This is a wonderful aid to making further choices about wider and narrower angle views.

My view of our vision and the selection of a “normal lens” in photography links with the attributes of many rangefinder cameras that make them compelling to so many photographers. For example the area within the 50mm lens frame-lines of a rangefinder camera’s viewfinder reflects our focus on the subject that we are seeing and concentrate on. But, the wider peripheral view (the context) seen outside those frame-lines is more indicative of our vision’s “normal” view (our personal way of seeing things normally) of the overall scene. That viewfinder allows the user to see his subject composition within its overall context of the wider environment.

It’s therefore logical that most photographers’ “normal” view equates to a 135 format focal length of between 35mm and 50mm, which range happens to include the human eye’s normal AOV as well as the 42mm diagonal measure of a 135 format film frame. However, that range should not exclude those photographers that work to or prefer a “normal” AOV equivalent to the wider 28mm and narrower 70mm focal lengths.

Therefore typically (and verified by a number of discussion groups), “normal” lenses in the major formats are likely to fall into the following ranges of focal lengths:
• 135 – 28mm to 70mm;
• MF (6x4.5, 6x6 and 6x7) – 60mm to 100mm;
• LF (assuming 4x5) – 120mm – 180mm.

Discussions with experienced amateur photographers in each format support that range.

For professional photographers, the selection of their “normal” lens is greatly influenced by their photographic genre. While a dedicated portrait specialist may see his world through a relatively narrow AOV such as 100mm (135 format equivalent); the dedicated panoramic landscape specialist may see his world through the eyes of a 21mm AOV (135 format equivalent). Equally, their lens kits are built around these focal lengths. The significance of a “normal” lens to them is that they have an exact understanding of how they normally see the images they make.

Among the iconic image makers, Henri Cartier-Bresson is said to have exclusively worked with a 50mm lens (135 format), while Ansel Adams often wrote that he preferred a narrower “view” to reflect what he saw he was seeing – approximately 100mm equivalent in 135 format (he shot mostly with an 8x10 view camera and occasionally with a 6x6 Hasselblad).

My views help explain why in 135 format rangefinder camera users such as Leica M users often prefer 35mm lenses as their "normal" lens - the everyday lens for taking in the scene ahead with an undistorted perspective – a natural / normal view. Surveys have shown that from the 1950s the 50mm was the most commonly selected “normal” lens; whereas in the past 10 years the 35mm has become that common selection.

Maybe 40mm is a closer to average human eyesight than 50mm, but the “normal” concept should not be a rigid one. Lens photographers’ preferences all differ (this may explain why so many rangefinder camera 40mm lenses been popular). Typically these users may have a lens kit of 24mm, 35mm, 50/75mm and 90mm. All lenses are balanced around the 35mm focal length. Alternatively users who prefer 50mm as a “normal” general purpose lens often have a lens kit of 21, 28mm, 50mm, 90mm or similar for the same reasons of balance.

Interestingly the 135 format rangefinder photographer often has a keen interest in the “street” photography genre. Consistent with that interest, his normal visual perspective is relatively wide to both capture the whole scene as well as help ensure a deeper depth of field and overall scene sharpness. As many live by 35mm lenses as live by 50mm lenses. Some even select their “normal” lens as wide as 28mm. What these photographers have in common is a clear understanding of how they see and how their eyes focus on a scene they wish to capture.

While a zoom lens can perform the role of a “normal lens”, it risks driving indecisiveness and confusion. Picture the novice in the field, constantly turning the zoom, not moving his feet and becoming distracted from “what he is seeing” by a myriad of framing choices. However, with a so-called “standard zoom” the trick is to determine one’s normal view; begin there and carefully decide if a wider or narrower AOV will help create the desired image.



Other formats:

In medium format (MF) photography the issues are the same. Experienced users' "normal lens" most commonly varies among 60mm, 80mm, 100mm (also affected by the image size – 6x4.5, 6x6, 6x7) - it's about how they see what they are seeing! Some match the focal length more to their general vision (60mm) or how they work; others simply have a format driven preferred AOV (e.g. 100mm) that may be “tighter” than their normal sight. For me it has been 80mm and is becoming 120mm as a standard AOV in which I prefer to see a 6x6 image - a 135 format horizontal equivalent of about a 75mm lens.

But, in large format (LF) photography I see things a bit wider and a 90mm lens is my "normal" AOV (a 135 format equivalent of about 28mm based on horizontal measure).

Additionally, and contrary to popular advice, one should NOT simply "select” any lens for other formats based on what you like in 135 format – normal or otherwise. While lens kits will have similarities, your use patterns will differ because they are often used in different styles for different purposes – “different horses for different courses”.


Conclusion:

Ultimately, my message is that understanding what focal length is your “normal” lens and why that is so can be very valuable to the quality of your image creation – likely the best quality lens in your kit; a logical corner-stone for building you lens range and selecting other focal lengths to add to it. If your lens kit is dominated by zoom lenses and you don’t have a prime lens that reflects the focal length of your “normal” AOV, I suggest you consider adding one to your kit.

Rethink your attitude to “normal” prime lenses; consider selecting a focal length that suits you, your sight, your visual preferences, how you work and add it to your kit (if you don’t have one). Then use it as the cornerstone of your lens kit. You may just find it becomes your favourite lens!

One of the best tips for developing your image making skills is to “train” you eyes. Fit your “normal” lens to a camera body and spend a day or so alone shooting a variety of subjects. You’ll find that you learn to move your feet, adjust the camera angle and frame images better than ever. It will make you think carefully about your image composition before you fire that shutter. Many keen photographers regularly do this to exercise their mind and creative eye.

After your “normal” lens images are developed look closely at them to discover what new techniques you have learned – how an image could have been framed better; why a good image is so good.

Although the development of automated 135 format SLRs and auto-focus systems were said to remove the “fuss” from image making and would allow concentration on composition; the reality is that can be more of a disadvantage. Camera automation, auto-focus and the use of zoom lenses, do more to distract the creative shooter than aid him – they often deprive the user from a true understanding of optical performance, exposure techniques, and depth of field and other critical attributes of great images.

Moreover a low understanding of the way we normally see images deprives us from understanding how any other focal length will help make a better image from what we are seeing. The use of our chosen “normal” lens to make an image or then decide to select another focal length for that shot; is valuable to better “seeing what we are seeing”.

A high quality personally selected normal lens can be a very low cost investment in valuable optics that may not only enhance your photography but give your whole lens kit greater meaning and future lens purchases greater value.

FOOTNOTE
The images appearing above were taken with what I describe my "normal" lenses in each format I shoot:
- Melbourne's Original Exhibition Building - XPan II and Hasselblad 45mm f4;
- Newcastle Nobby Beach - Linhof Technika V (6x9 back) and Rodenstock Grandagon-N 90mm f4.5;
- Bushman's Hut - Leica M7 and Summicron-M 35mm ASPH f2;
- Resting at The GPO - Hasselblad 503CW and Makro-Planar 120mm f4.

Photos and text copyright of f8Vision