Basic Concepts of Camera Ergonomics

CAMERA ERGONOMICS

Part 5  Introduction to some basic concepts

Author  AndrewS

Introduction    Modern cameras have a vast array of features, functions, modes, options and controls.   Mirrorless interchangeable lens technology has given birth to a plethora of cameras with different shapes, styles, formats, capabilities and sizes, the like of which has not been seen before in the history of photography. Designers of these electronic marvels want  to produce brilliant products, each with a unique selling point,  which will convince prospective buyers to say "Here is my money, I will buy it".

But there are three elephants in the room with those designers.  Yes, they need a really big room !!

The first is that the native capabilities of  the people who use these cameras have not changed much in the last 50,000 years or so.  Sure, users can learn new skills, but they cannot change the size or functional anatomy of their hands.

The second is that beneath the fancy electronic bells and whistles, the great majority of modern cameras work just the same way as cameras did 100 years ago.  Exposure is controlled by alterations to the Time Value (Shutter Speed), Aperture Value (Fstop) and Speed Value (ISO Setting). The lens must be focussed, unless one is using a Lytro Light Field camera, but that is a story yet to be told.  All this must happen in good time, lest one's subject wander off  before the camera work is done.

The third is that despite some very clever technology, fully automated exposure and focus does not always deliver the required outcome. In consequence the world still needs cameras which can be directly controlled by the user.  These cameras have a complex human machine interface (HMI) and are difficult  to design well. I know this last statement must be true because I  have, in the last few years,  encountered so many cameras with a clumsy HMI.

Conceptual complexity    I want to highlight two fundamentally different types of problem, both of which challenge camera designers and engineers.

The first type of problem is conceptually easy buttechnically difficult to solve. The design of a camera sensor is like this. The concept is straightforward enough. Sensors need better resolution, lower noise, better color reproduction,  higher dynamic range and faster refresh rates.  In other words, the questions which need to be answered are reasonably easy to articulate. Of course, the technological challenges are great.

The second type of problem is conceptually difficult but technologicallystraightforward. Achieving good camera ergonomics is like this. There is currently a deficit of language and classification by which to articulate the questions which need to be answered in order to achieve good ergonomics. There is an old saying........"If you don't ask the right question you cannot get the right answer". This is a key issue for ergonomics.

The technological challenges are not great. They involve such things as camera size,  handle shape, type and location of controls, all things which have to be decided  with any camera.

My experience with many cameras over a 50 year time span is that camera makers are much better at dealing with technological challenges than conceptual issues in the realm of ergonomics.

Camera users   In the operational sense, there are really only two types of camera user.  The first and by far the most numerous is the snapshooter. The snapshooter is too busy enjoying life to be bothered with changing lenses or wondering what an f stop might be. In the second, smaller but more demanding group we find the  controllers. These people want to take charge of the process of making photos in the quest for better results. They want direct control over all aspects of camera function, in particular primary and secondary exposure and focussing variables.

There will, of course, be  snapshooters seeking to upskill, controllers wanting to reduce the complexity of life and a variety of other people who at any given time, find themselves between the two user groups. My thesis is that these  inbetweeners will gravitate one way or the other in due course. If  I am right about this it follows that cameras pitched to the inbetweeners will be perceived as overly complicated by  snapshooters and too limited by  controllers, ultimately appealing to neither group.

Controllers have more explicit and numerous requirements for holding, viewing with and operating a camera. Provided the size and weight are not excessive, a camera designed for controllers will suit snapshooters just fine. This assumes that when a fully automatic shooting mode is set, most of the hard controls are disabled. Such a camera will allow the snapshooter to progress to controller if so desired. The reverse is not true. A camera designed with minimal controls for the snapshooter will not  satisfy a controller and provides no upgrade path for snapshooters wanting to improve their camera work skills.

Phases of camera operation    It is useful to describe four phases of camera operation. Making these phases explicit helps to clarify which tasks need to be completed at each  phase,  what kinds of controls are most appropriate for those tasks and where on the camera they might best be located.

Setup Phase  In this phase the user delves into a menu, or more often a hierarchy of menus, to set the hundreds of variable parameters available. Setup is best conducted at leisure.

Prepare Phase   In the minutes prior to making photos, the user will want to adjust a range of  camera settings for the present environment and photographic assignment. This might be a birthday party indoors with flash, landscape on a sunny day.... and so forth.

Capture Phase  Now the photographer is in the process of taking photos. The controller type camera user will want to quickly evaluate and alter key exposure and focus variables in a time frame of  just a few seconds. This phase places the highest demand on the operational performance of both camera and user.

Review Phase    In this phase captured photos are reviewed. Ergonomic demands are not as intense as in the Capture Phase,  but the process still needs to be streamlined and efficient.

Primary, secondary and tertiary exposure and focussing controls   It is most desirable to explicitly rank the tasks of camera work by their urgency level in the capture phase.  This will help us to better understand what kinds of interface modules (buttons, dials, touch screen etc) might be best for each task, how each module should operate and where it would best be located.

Two key functions which every camera must perform immediately prior to image capture are Exposureand Focus.  Let us look at exposure first.

There are three Primary Exposure Variables. These, as I referred to in the introduction, are

* Time Value (shutter speed) 

* Aperture Vale (f Stop) and

* Speed Value (ISO Setting). 

These three have to be adjusted interdependently, by which I mean if you change one then at least one other value must also alter to maintain correct exposure. I call the selected combination of the three variables the "Firing Solution". For instance  1/15 second @ f16, ISO 100, gives the same exposure as 1/1000sec @ f4, ISO 800.  The first firing solution might be suitable for a tripod mounted landscape shot, the second for hand held telephoto sport/action.  In order to find the optimum firing solution in each photographic situation the photographer can either

a)  Set the camera to fully automatic mode and hope for the best, or

b)  Set the camera to one of the "Scene" modes and continue to hope for the best, or

c)  Take control of the process and make a conscious decision about the firing solution.

In order to implement the third option effectively the user has to learn how to use apertures, shutter speeds and so forth  and the camera has to have the right feature set, with good enough ergonomics, to allow the user to take control of the process.

Primary exposure variables need to be clearly visible in the viewfinder and on the monitor at all times. They are optimally displayed beneath the image preview, not overlaid on the preview which is much more difficult to see clearly.  They must be able to be adjusted very quickly, by feel, while continuously viewing the subject in the viewfinder. This means they need dedicated, direct acting  hard controls, immediately accessible to the right index finger without having to shift grip at all.

Secondary Exposure Variables   These include

*Exposure Compensation

*Program Shift in P Mode

These variables are not primary in the sense that they are not directly involved in the firing solution. However they do need to be adjustable at the same level of immediacy as the primary variables. Again this means dedicated hard controls, directly accessible to the right index finger (preferred) or thumb (second preference). 

Tertiary Exposure Variables  Here we can place a list of parameters which might differ somewhat between users, according to individual preferences in ways of operating a camera.

These might include

*Exposure metering pattern

* Auto Exposure Bracketing

* White Balance

* Link metering to focus area

* Dynamic Range enhancement

* Others depending on preference

These parameters need to be readily accessible in the Prepare Phase of camera use. This is usually best accomplished by allocating them to a "Quick Menu" and/or in some cases  to a physical Drive Mode dial or lever. It should be possible to pull user selected items up from a main menu and relocate them to the Quick Menu.

It should never be necessary to enter a Main Menu to access primary, secondary or tertiary exposure variables. 

Primary focussing controls  These must be adjusted or checked prior to every image capture.

* Start/Lock autofocus  or

* Manual focus

These are maximum priority controls which require dedicated, hard, direct acting interface modules located for immediate operation while continuously viewing the subject in the viewfinder and without having to shift grip with the right or left hand.

By tradition manual focus is controlled by a rotating ring on the lens, operated by the left hand. If the manual focus ring is correctly  located this system works well and divides labour between the right and left hands.  Autofocus, also by tradition, is activated either by half press of the shutter button using the right index finger or by pressing a dedicated button on the rear of the camera with the right thumb. This latter option has the advantage of separating focus from capture, a particular advantage with moving subjects.

Secondary focussing controls  These require fast, easy access but are not usually required prior to every capture.

* Change position/size of active AF area

* Change position/size of active MF area

Direct acting, dedicated, interface modules are required to permit these controls to be made quickly, without interrupting the flow of the capture process.

The user interface system needs to be like that of a motor car in which the driver does not have to think about how to adjust the primary controls such as steering, acceleration and braking.

A good ergonomic case can be made for allocating exposure controls to the right index finger and autofocus controls to the right thumb.

Tertiary focussing controls  Here we can find a range of options and variables which differ with the individual camera. As cameras become more sophisticated and complex this list inevitably grows.  It would  be desirable for items in this group to be user selectable from a main menu and transferred to a Quick Menu. Some could usefully be allocated hard controls, provided those controls were located on the camera in second tier positions, so as not to supplant controls for Capture Phase actions in first tier positions. They include

* Focus type, phase detect/contrast detect

* AF Mode, Single (one shot) continuous,  tracking (predictive)

* AF Area (type),  Single point (selectable), multi (auto select), Multi point clusters, Face detect, etc

* AF tracking mode (focus stays on one target/group or is handed to adjacent target/groups)

* Auto enlarge view with MF activation  ( 2x, 5x, 8x etc)

* Other MF assist (peaking mode or other technology)

* Lens based controls might include AF/MF, Focus distance limiter etc.

These items need to be adjusted in the Prepare phase of camera operation.  Much user frustration will result if they are allowed to languish in a main menu.

Photographs

The two photographs are different views of a mockup camera.  It might look a bit rough but the exact body shape and the precise location in three dimensions of all the interface modules (buttons, dials etc) have been very carefully evolved over many trial versions for optimum functional efficiency.

On picking up the camera the user can feel with the right index finger if it is switched on or off.  The "set and see" type dial on top instantly shows the current Shooting Mode.  The adjacent "set and see"  Drive Mode lever gives a direct reading of the current setting. Both of these can be quickly adjusted in seconds. The handle and thumb rest have been very carefully sculpted  to fit the right hand in relaxed half closed grip as described in the section on functional anatomy. The quartet of interface modules consisting of Shutter Button, Main Control Dial, Button 1 and Button 2, allow Metering, AF start, Change Aperture, Shutter Speed or Program Shift, Change ISO and make the exposure very quickly, with just the index finger, while looking through the viewfinder and without changing grip with either hand. Button 6 allows for AF start/lock without changing grip. The JOG lever #7 allows instant shifting of active AF area size and position in Capture Mode while looking through the viewfinder and without shifting grip with either hand.  All interface modules can be reconfigured to user requirements and all will have Mode Dependent functions. In other words they have one set of functions in, say, Capture Mode and a different set of functions in, say, Review Mode.

   

Functional Anatomy of the Hand

CAMERA ERGONOMICS

PART 4    Functional anatomy of the hand

By AndrewS

Ergonomics has been defined as the study of designing equipment and devices that fit the human body, it's movements and it's cognitive abilities. (Wikipedia, 2011)

Most cameras are hand held devices so it makes sense to begin a study of camera ergonomics with an exploration of the range of movements and capabilities of the hand and fingers.

I take it as self evident that a camera should be designed to fit the hand, not the other way around.

Lateral dominance   Before going further, I should raise the issue of dominance.  Most humans are right side dominant. This means they perform better  at writing and operating devices with the right hand.  Most also are right eye dominant.  These people have a left side dominant brain. About 10% of people are left handed, although about half of these also have left side brain dominance. Crossed and/ or mixed dominance is not uncommon.

Cameras are designed to be operated by right handed people. Those who are left handed are not catered for. In this case the user has to adapt to the camera which is ergonomically suboptimal. However, most manage to train their non dominant side to do the job. They have little choice, until someone comes up with a right/left inverted camera shape.

Photo 1 Dimensions

Size    The right hand you see in the photographs is the author's. In Photo 1, Dimensions you can see it measures 190 mm long by 96 mm wide.  Wikipedia gives 189 x 84 mm as average for an adult male and 172 x 74 for an adult female. Obviously hands vary in length, width and finger thickness. However reasonably healthy hands all function the same way.  Cameras need to be designed so that they readily accommodate most of the hand size variation found in the general population.

Photo2 Skeleton

Photo 2 shows the skeleton of a hand and wrist with 27 bones.   There are 8 carpal bones in the wrist giving it flexibility in all directions without which operating a camera would be almost impossible.  Next come the 5  metacarpal bones, then the phalanges, of which the thumb has 2, the other fingers 3 each.

Thumb Opposition    The thumb metacarpal bone can rotate to allow the tip of the thumb to touch the tips of the other fingers. This is called opposition and is essential to gripping and operating a camera. Look at Photo 3 Palm flat,  Photo 4, Clench no opposition and  Photo 5, Clench with opposition.  You can see that if the hand tries to grip onto anything without thumb opposition, the grip force is directed into empty space and is dissipated. But with opposition in play the grip force of the fingers is directed  into the tissues of the base of the thumb, lying over the rotated metacarpal bone. Thus the hand can grip and hold things securely.

Photo 3 Palm Flat

Photo 4 Clench No Opposition

Photo 5 Clench with Opposition

Sensory capability    To operate a camera the fingers must detect touch and position to a high level of sensitivity.  This is particularly the case with modern electronic cameras some of which have many controls. My reading of research on this subject would indicate that sensitivity increases towards the fingertips, being greatest just below the nail bed. It would also appear that the thumb is less sensitive to touch discrimination than the other fingers. These characteristics are important to the design of physical controls.

Photo 7 Relaxed Top View

Photo 6 Relaxed Rear View

Basic Hand Posture      See Photo 6, Half Closed Relaxed Rear View and Photo 7, Half Closed Relaxed Top View.  This is a relaxed natural position for the hand to adopt.  Muscle force is required to clench the fingers further,  straighten them, or move them into a different alignment.  A properly designed camera will be sized and shaped to fit easily into the relaxed hand, which can then grip the camera securely with minimal stress.

Movements    Each finger has a range of possible movements which are critically important to the design of the shape, layout and controls of a camera. I find it useful to categorise fingers as "grippers" or "controllers".

Photo 8 Index Pos 1

Photo 9 Index Pos 2

Photo 10 Index Pos 3

Photo 11 Index Pos 4

Index finger  This is a controller. It has good position and touch sense. It can curl and  straighten in the line of the finger. It can also angle from side to side at the metacarpophalangeal joint over a small but vitally useful range.  These movements can take place without the slightest change in the position of the hand or any other finger. You can demonstrate all this for yourself. These characteristics make the index finger the best choice for actions required to be made during the capture phase of photography, that is,  while one is actually in the process of making photos. Please see the series Photos 8, 9, 10, 11.    I elected to demonstrate these movements on a mockup camera to better illustrate their practical utility. The index finger can easily operate four items, as shown here, by feel, without having to look at the finger or the control items, and without having to disrupt the basic grip. On the mockup the four modules are Shutter Button, Main Control Dial, ISO Button and Exposure Compensation Button.  This enables all primary (Aperture, Shutter Speed, ISO) and secondary (Program Shift, Exposure Compensation) exposure parameters to be quickly and confidently adjusted, auto focus achieved, auto exposure achieved then the photo captured, all with just one finger.

Middle, ring and little fingers.  These are grippers, usually operating together as essentially one gripping unit. They will function  best if the camera is designed so all three can get a proper hold on the camera's handle.

Thumb  The role of the thumb in holding and operating a camera is complex. In most cases it has to perform both gripping and controlling functions. As we will discover it is very difficult to achieve both at once.  The thumb has three main movements: Opposition, Flexion / Extension and side to side movement. Opposition as we have already discussed is by rotation of the metacarpal bone at the carpometacarpal joint. Flexion / extension can occur at the metacarpophalangeal joint and the interphalangeal joint. Side to side movement occurs at the carpometacarpal joint. Note this is quite different from the index finger which uses the metacarpophalangeal joint for side to side movement.

So what ?? do I hear you asking ?? Well, so quite a lot as it happens.

You need to have the thumb metacarpal in opposition to be able to hold onto the camera with the right hand. Try this for yourself. Hold a camera as usual, in your right hand.  Then open up the ball of your right thumb (the part over the metacarpal bone) derotating the metacarpal bone and releasing the opposition posture. The camera will immediately fall to the floor unless you catch it with the other hand.

Photo 12

Photo 13

Now look at photos 12, Press Thumb IP Joint Extended and  13, Press Thumb IP Joint Flexed. There are lots of buttons and dials on the back of modern cameras. Some can be pressed / operated with the thumb held straight, as in Photo 12. With the thumb in this position opposition at the metacarpal bone is present and the user's grip on the camera can be maintained.  But other cameras have controls which require you to flex the thumb in order to operate them. Sometimes the controls are inaccessible to a  straight thumb, sometimes a semi submerged dial can only be operated with the tip of the thumb.  In either case, flexing the thumb forces the metacarpal to derotate and opposition is lost. In this case you cannot hold the camera with the right hand  and operate the thumb controls at the same time. You must support the camera with  the left hand while the right thumb is operating the controls. During this process the index finger is sitting idle, when it could have been operating controls with no disruption to the right hand grip at all.

Photo 14,  Thumb Lateral Movt Metacarpal  illustrates side to side movement of the thumb, shown in place on a mockup camera. This movement is articulated at the bottom of the photo, not where the side to side arrows are shown. As a result, this movement disrupts the placement of the ball of the thumb and to some extent destabilises the grip. In practice a small amount of side to side movement by the thumb is compatible with maintaining grip. In the case of the mockup shown here the AF start button can be activated by rolling the thumb 3mm to the right and the AF position jog controller is easily reached and operated by moving the thumb 10 mm to the left, maintaining opposition.

Why does all this matter ??  There are four phases of camera operation; Setup, Prepare, Capture and Review. In the Setup, Prepare and Review phases, it is perfectly satisfactory to fully support the camera and lens with the left hand while operating buttons, dials or even touch screen controls with the right thumb. But in the Capture phase that is not acceptable. While actually in the process of taking photos the operator needs to be able to adjust all primary and secondary exposure and focussing parameters while continuously viewing the subject  with both  hands firmly supporting the camera.

Many modern cameras require derotation of the thumb metacarpal or in some cases complete removal of the base of the thumb from the camera in order to access the controls required during Capture phase operation.  Many also require the user to look at the controls in order to hit the right one. This destabilises the right hand grip, jiggles the camera, takes the user's eye off  the subject and disrupts the flow of taking photos.  Many of these camera work just fine in one of the fully automatic, snapshot settings, where the camera makes all the key exposure and focussing decisions. But they are most frustrating to operate in one of the user control modes, for instance one of the P,A,S,M shooting settings.

A Brief Ergonomic History of Cameras

CAMERA ERGONOMICS

Part 3   A brief history of cameras from an ergonomic perspective

 Author    AndrewS 

Writer's experience   Over the last 50 years, I have owned and used all the main camera types referred to in this section except the Eastman Kodak snapshooter and Brownie types, and obviously, nineteenth century cameras.

The nineteenth century

The first photograph was made by Joseph Nicephore Niepce in 1826. He was followed by Louise Daguerre whose research led to the Daguerrotype in 1839.  The equipment  used in these pioneering photographic exploits was heavy, complex and difficult to use. The processes were dangerous. Daguerre's early ventures required highly toxic chemicals in the form of iodine and mercury vapours.

All this changed in 1888, when George Eastman produced a camera for the masses, and with it the famous slogan "You press the shutter, we do the rest".  The snapshooter was born.

The twentieth century

The popularity of snapshot photography gained further impetus in 1901 with the advent of the Kodak Brownie camera, costing one dollar.  The Brownie had acceptable ergonomics. It was easy to hold and carry.  Most versions provided a useful, if not terribly accurate, viewfinder. Operation was reasonably simple with few controls, although a certain amount of fiddling with levers was part of the process.. A potential source of user frustration was loading and unloading the roll of film, which some people could have found difficult. And of course you had to remember to wind on the film after each exposure..............

BoxBrownie

Professional photographers used large format cameras taking individual sheets of 4x5 inch or larger film. These also delivered decent ergonomics in the sense that many models had well located and designed controls. Of course the camera had to be tripod mounted, the image preview under the darkcloth was inverted vertically and horizontally, it took about 30 minutes to set up for an exposure and there were at least 20 ways the operator could ruin a shot by forgetting an item on the shooting checklist.

Large Format

Press photographers in the early part of the twentieth century managed to use a type of large format camera (the Speed Graphic was a favourite)  for rapid response, hand held reportage. This was a triumph of human dexterity over limitations of the camera type.

In 1929, Franke & Heidecke produced the first Rolleiflex twin lens reflex (TLR) camera and others copied the basic design concept. The TLR provided several ergonomic advantages over existing camera types. One was full time live view on the focussing screen. The image was laterally inverted, but most users adapted to this quirk. The camera was easy to hold while shooting and the controls were reasonably well laid out.

TLR

You had to wind a cranking lever to advance the  film after each exposure which sounds tedious but could be done quickly with practice. Many professional photographers used TLR's for a wide range of assignments. The TLR's compact size and ease of handling, compared to a view camera, also encouraged the rise of a new type of photographer, the enthusiast amateur.  This photographer was well versed in the complexities of shutter speeds, apertures, film speed and manual focussing, but chose not to make a living from photography.

In terms of camera use, the enthusiast amateur and professional were both controllers. They wanted to take charge of the process of using the camera in the quest for excellent results.

Film Rangefinder

In 1925  Ernst Leitz Optische Werke produced the Leica 1 camera. This was one of the first cameras to use the "miniature" format of  24 x 36 mm on  perforated 35 mm movie film. Compared to all previous cameras the Leica was amazingly small and with practice reasonably quick to operate. A built in viewfinder and  rangefinder were introduced in 1932, but the early viewfinders were very small. Some modern commentators wax lyrical about the ergonomics of Leica M series cameras from the M3 of 1954 onwards.  These cameras do have some good features.  They are compact and easily carried. Current settings for aperture, focussed distance (on the lens) and shutter speed (on the top dial) are always visible at a glance and easily adjusted.  Shot to shot operation of the camera is simple, direct and fully controlled by the user.

But there are less appealing aspects of the design. The ISO button on the M9 is irritatingly on the left side of the camera. So to change ISO you have to drop the camera down, remove the left hand from the lens, push and hold the ISO button while turning the rear dial.  Wide angle lenses require the user to look through one window to focus and a different window to frame the shot.

Clasic Film SLR

One of photography's very best ideas was the Single Lens Reflex (SLR) camera. Models for 35 mm perforated film and for 120/220 paper backed rollfilm were released in the late 1940's. This type of camera solved most of the problems inherent in the TLR and Rangefinder types. It became very popular with professional and enthusiast amateur photographers alike. Most were compact, with good handling, viewing and operating characteristics. Over the years the SLR grew larger and heavier, as motor drive, batteries, autofocus  and electronic controls were added to the package.

Film Compact

The invention of motor drive led to the development of  fully automatic compact cameras. These replaced the Brownie to become the snapshooter's favourite. Many had a motorised zoom lens, automatic exposure, automatic focussing, a decent viewfinder, decent handling and sufficient image quality for the target user group. Many had a semi automated film loading and rewind system for ease of use.  They sold by the millions just as Brownies had done in former times.

The twenty first century

It is only 12 years old but this century has already seen more changes to cameras and the photographic industry than took place in the entire twentieth century.

The main changes have been:  Digital image capture, increased complexity, electronic camera operation, the rise and rise of the smart phone as the snapshooter's camera of choice, the decline of prints and rise of the world wide web as the place to view and share photographs and  the invention of the mirrorless interchangeable lens camera.

Many traditional camera makers have failed, their place taken by electronics megacorporations which may or may not have an ongoing committment to  making cameras.

In February 2012, what camera types are available ?

There are still plenty of snapshooter's digital compacts to be had, increasingly featuring some kind of internet connectivity.

Premium compacts seek to provide better image quality and a more engaging user experience for the advanced amateur and even professional photographer. Most of these suffer from the absence of a built in viewfinder or they provide  a small cropped optical viewfinder with parallax error and without  shooting information. If these cameras had a high quality electronic viewfinder (EVF) they would be much more appealing to their users.

Digital SLR's (DSLR) continue to sell well to professional photographers, advanced amateurs and even snapshooters, who put the camera in fully automatic mode and leave it there. Many DSLR's feature reasonable ergonomics but they could be improved by a more considered approach to basic ergonomic principles. Many place interface modules (buttons, dials etc) in suboptimal locations.

Many models have a  mix of traditional SLR operation, with fast but inconsistently accurate phase detect autofocus awkardly married to live view and video function with (usually) accurate but slow contrast detect autofocus.  But you get either one or the other, they are not integrated in seamless fashion.

CSC No EVF

Last but not least we  have the mirrorless compact system camera (CSC).  This camera type first came to market near the end of  2008 and has yet to establish a clear identity. The type also requires further development before it can be considered to have reached technological maturity. As I write this in February 2012 most CSC's  have a feature set which puts them somewhere between an advanced compact and a mid range DSLR, without being able to make a convincing case to replace either. They have features which would make them a daunting choice for the snapshooter. These include (not necessarily all in the same camera)  interchangeable lenses, a  long and complex  list of menu items, sophisticated operating options such as a choice between electronic and mechanical shutter and many capabilities such as in camera panorama stitching, high dynamic range image capture etcetera, etcetera.....  So they are really out of the snapshooter's league.

But they fall short of meeting the expert/enthusiast/professional photographer's requirements also.  This is due to deficiencies in two areas, technology and ergonomics.

CSC With EVF Good Ergonomics

The technological issues are specific. The first is the state of development of the electronic viewfinder (EVF). Even the best at present cannot keep up with the optical viewfinder (OVF) of a good DSLR with respect to refresh rate and dynamic range. As a consequence when shooting at fast frame rates the EVF displays a review of the previous frame, not a preview of the next frame. This is highly disconcerting when attempting to follow action.

The second technological issue is that most CSC's have not yet implemented effective, fast,  sensor based,  predictive tracking autofocus. One recently released CSC does have this feature but it's holding and operating characeristics have drawn much well deserved criticism.

CSC Poor Ergonomics

My main issue with most CSC's on the market as I write is their compromised ergonomics.  In fact my interest in ergonomics was sparked by my frustrating experiences with several CSC's.    Many have no built in viewfinder, no handle for the fingers to grip, or just a vesigial excuse for one, no thumb rest, no Mode Dial on the top plate. Some have a handle so poorly designed the fingers have to be contorted into unnatural positions in order to operate the controls. Many require a trip to a labrynthine and convoluted menu system for primary and secondary exposure and focussing controls. One recent offering makes the right thumb operate three dials while the right index finger has none. Please refer to Part 6 of this series for a discussion about optimum finger task allocation.

Form, function and style

Any exploration into the history of camera design will reveal an ongoing dialogue between form, function and style, since the earliest days of photography.  The layout of film cameras for most of the 20th century was largely determined by functional imperatives. Consider, for instance a traditional 35 mm SLR such as the Pentax Spotmatic.  The mirror box had to be located in the middle, with the pentaprism on top and film path running from the donor spool on one side to the receiver spool on the other side. All the controls worked by direct mechanical connection so they had to be where you find them on this camera and many others of the same basic design. The stylists had their say no doubt but their options were limited by the camera's mechanical natureand the constraints of metal working technology at the time. It seems to me that these restrictions kept camera designers grounded in functional reality. The result was several decades of classic SLR cameras which had decent ergonomics.

Smart Phone Cam

Fast forward to the present and  I think it is clear enough that the photographic industry is undergoing it's biggest upheaval ever, with multiple disruptive technologies from outside photography overthrowing the status quo as never before.

It is not surprising therefore to find that the people who make and market cameras appear to be unsure of the way forward.

Consider the  electronic, mirrorless, interchangeable lens camera. Now, with modern materials fabrication technology the body can be literally any shape at all. An electronic viewfinder and all the controls can be located anywhere, with very little constraint.  Controls can be accessed by hard modules (buttons, dials) or soft interfaces (touch screens and similar). Each interface module can be assigned a function selected by the user from a potentially long list of options. You might think this situation would liberate camera designers from the shackles of yore and free them to develop superb ergonomic creations perfectly adapted to the user's functional requirements.  But it has not happened.  In my assessment, the human machine interface (HMI) of modern cameras is getting worse, not better.

Camera makers say they are making product development decisions based on feedback about prospective buyers wants, likes and preferences. As I discussed in Part 2 of this series, these buyer attributes are transient, idiosyncratic and often unformulated.   They need to be considered separately from, not as a substitute for,  basic principles of ergonomic design.

It appears to me that even long established camera makers do not have an in house book of design principles and guidelines to optimise holding, viewing and operating cameras, in other words, ergonomics. This becomes glaringly apparent when  long established makers of well regarded SLR's and DSLR's produce their first CSC with a multitude of deficiencies in holding, viewing and operating capability. It is as though these makers learned no basic principles from their SLR experience which could be applied to the CSC.

This series of articles is my attempt to rectify that deficiency.

The articles are directed primarily at camera buyers and users in the hope that they will become more sophisticated and articulate in providing feedback to camera makers about the design requirements of a camera which will be a pleasure to use rather than a set of frustrations to be overcome.

Developing Methods to Study Camera Ergonomics

CAMERA ERGONOMICS

Part 2,  How I developed a method for systematic evaluation of camera ergonomics

Author  AndrewS 

In the early days of my quest, I read many camera reviews. I was surprised to find a paucity of systematic description of ergonomic issues.  By way of contrast I found extensive presentations of a multitude of factors affecting image quality. There was a well developed language and taxonomy (classification by principles) of image quality, but nothing remotely comparable for ergonomics.

This was disappointing. My long experience of using cameras had led me to realise that once a camera's image quality was "good enough" for my purposes, it mattered not that some other model might have slightly better image quality. The things which determined if I could live with and continue to enjoy using a camera were it's handling, viewing and operating qualities. In a word, ergonomics.

Likes and preferences     As a method  for evaluating these qualities I considered lending some cameras to people and seeking their feedback. But on reflection I realised this approach had serious deficiencies. The feedback received would consist largely of  the participant's "wants", "likes" and "preferences". There are three  problems with these  attributes.

First they are transient. The things which a person likes today will be different next week or next year as a consequence of that person's experience.

Second  they are idiosyncratic. They are meaningful to that individual for the person's own reasons, whatever they may be, and cannot be assumed to generalise to anybody else.

Third, they are often unformulated.  By this I mean that when a person is asked to say what they "want" in a house, car, partner, camera etcetera, they will often say one thing but after using, living in or with that choice, come to realise they really would rather something or someone else. 

I wanted to develop a robust, systematic method of describing and evaluating camera ergonomics based on observations of fact which could be made by anybody having access to the camera, independent of wants,  likes or preferences.  

Functional anatomy of the human hand   One of the basic principles of ergonomics is that the tool should fit the user, not the other way around.    As the "tool" in this case is a hand held device the logical place to start is a study of the capabilities of the hand.  I have a medical background which made the task easier. I examined and photographed my own hands, which are of average adult male size and shape,  in a variety of positions. I investigated which positions are natural and relaxed, which are cramped and feel unnatural. I explored the range and direction of movement of each of the fingers, exploring which operate best as "grippers" and which as "controllers".

Handle styles and mockups   Many cameras have some kind of handle on the right side intended to improve the user's grip on the device.   Looking at many cameras I realised that I could classify them broadly into four types, with intermediates not uncommon. These are No Handle, Mini Handle, Projecting Handle and Parallel Handle. Big cameras often use the projecting handle. I noticed that many camera makers use the same projecting handle style on their small cameras, with unsatisfactory results. Hands do not shrink to fit smaller cameras, which must be shaped differently from their larger siblings if the result is to work properly.

I made several handle mockups from scrap wood and used these to explore the relationship between the handle and the hand without the distraction of an actual camera. This process led me to some very clear insights about handle design in cameras of different sizes.

Full camera body mockups   The next step was to make some full camera body mockups, also from scrap wood I had lying about in the garage. With each project I used an existing lens mount and flangeback distance as the starting point, assumed a design with inbuilt eye level viewfinder and 75mm monitor, then built around this a shape which best fit my hand. In the process I gave considerable thought to the way smaller and larger hands would interact with the grip. I whittled and played around a lot with pieces of wood, altering the shape many times until it felt comfortable, secure and stable in my hand.

This exercise provided a great deal of insight into the way all the different parts of a camera relate to each other and to the user's hands.  I discovered that large and small cameras can  be designed for satisfying ergonomic performance but there is a size  below which good handling is difficult to achieve.

Camera use task analysis

Cameras come in a great variety of shapes and sizes. They have a range of different specifications and capabilities.  But in every case, the user has to carry out a series of tasks in order to operate the device.  The principal tasks are Holding, Viewing and Operating.

The human assets which do the work are

* Hands and Fingers which must  hold and operate the machine simultaneously

* Eyes to view the subject and camera data

* Brains with cognitive ability to form and carry out the photographic intention

I realised that a well designed camera would fit the user's hands, eyes and brain to streamline the performance of each of the main tasks of camera work.  It seemed to me that a practiced user would have to pay very little attention to the process of using a well designed camera. This would allow the user to direct most of his or her attention to the subject.

Task analysis by timeline

I found that my analysis of camera operation became much more coherent when I defined four phases. These are Setup, Prepare, Capture  and  Review.  Each phase has a different set of tasks and time constraints.

Task analysis by hierarchy

The two critical operations which must take place immediately before image capture are Exposure and Focussing. Within these there is a hierarchy of parameters which must be controlled. To make sense of this I have divided them into Primary and Secondary Capture Controls. Primary controls require a more direct and immediate adjustment procedure than secondary controls.

Analysis by user group   From an operational perspective there are two types of camera users.  Snapshooters have better things to do with life than bother about apertures, shutter speeds, etc.  Controllers want direct control over camera functions in the quest for better results. The most difficult camera to design is one which meets the requirements of both groups. On thoughtful reflection about this I realised that the issue is ergonomic in nature. It is separate from other considerations such as whether the photographer is a beginner or expert.  There are plenty of experienced Snapshooters out there and more than a few inexperienced Controllers.

Time and Motion studies   In 1948 Frank and Lillian Gilbreth wrote a book, "Cheaper by the Dozen" which popularised the concept of time and motion study.   I used these ideas to analyse how cameras operate. I dissected each action required to make something happen on a camera. I counted any required changes to the grip with either hand. I counted the number of button presses, screen pushes or whatever a particular camera required. I noted whether the hands or fingers maintained a relaxed, neutral posture or whether they were required to stretch into uncomfortable positions. I noted whether controls could be operated while continuously viewing the subject. I noted whether the operation of controls was integrated with the capture process or a distraction from it.

I noted huge differences in the Human Machine Interface (HMI)  between cameras of similar size and general appearance. It became apparent that the controls of a camera could in many cases have been dramatically improved by a relatively minor repositioning and retasking of control interfaces (buttons, dials etc). In other cases nothing short of total redesign from the chassis up would improve the situation.

Using a camera: Improved understanding by analogy with other activities    Increasingly, the corporations which make cameras have a very big  presence in the market for touch screen gadgets. Many of these can take photos. This could easily lead one to the idea that smart phones, touch pad devices and cameras are analagous. My analysis leads me to a different understanding entirely. The way a camera operates is more like a motor car than a touch screen device. The driver of a motor car looks through the windscreen at the roadway and operates the vehicle's controls entirely by touch without taking his or her eyes off the road and without having to think much about the process of operating those controls. The user of a touch screen device looks at the device, not through it, and directs his or her attention to the symbols on the screen. Ideally a photographer looks through the viewfinder at the subject and operates the controls by feel without having to distract his or her attention away from the subject by looking at those controls. If cars were designed to operate like touch screen devices everybody on or near the roadway would die.   Presumably nobody will die if cameras operate this way but there will be many lost photo opportunities and the user experience will be less enjoyable than it could be.

The Style factor    Style has always been  a factor in camera design. I gained new appreciation for the importance of style when I made full body mockups.  Some of these had excellent handling qualities but looked strange to my eyes. When working with actual cameras I realised that many of these were shaped to conform to a particular style, sometimes to the detriment of handling qualities.

Size Matters   The advent of mirrorless interchangeable lens technology was like the starting gun for a race between  manufacturers to  produce the smallest camera, as if small size had some intrinsic virtue. After using several of these cameras over a two year period, I came to realise that some were so small that their holding, viewing and operating functions had become impaired. In their quest for the tiny championship, cameras discarded the inbuilt eye level viewfinder, inbuilt flash, hotshoe and shooting Mode Dial. Many had a reduced set of tiny, hard to feel controls, forcing the user to either stay in snapshot mode or fiddle with menus and workarounds to access primary exposure and focussing parameters. this experience helped me to gain a sharpened understanding of the HMI.

Photographs    This little series of photos illustrates a time and motion analysis of a single task, that being to shift the active AF area from the center to a peripheral location in the frame.  

Photo 1A Camera A Start

Photo 1B Camera B Start

 Photo 1A and Photo 1B.  We begin with each camera being held in a comfortable fashion for image capture.  Camera A has a direct manual zoom operation requiring two fingers of the left hand to be on the lens. The zoom action of Camera B is operated by a lever around the shutter button. therefore the left hand can continuously hold the body of Camera B.  Note, by the way, the right hand position on Camera B is more natural, that on Camera A more cramped, due to the different handle and thumb rest design.

Photo 2A Camera A Step 1

Photo 2B Camera B Step 1

Photo 2A, Photo 2B   Step 1. For Camera A the left hand must be lifted completely off the lens and brought back to press the AF button on the left side of the monitor. The button cannot be located reliably by touch, so the operator has to look away from the monitor to see the button.  For Camera B the right thumb has to drop down slightly to find and press the required button. This needs only a small movement of the thumb which can easily find the button by feel so the operator can continue to view the subject. The left hand stays in place now and throughout the task.

Photo 3 Camera A Step 2

Photo 3    Step 2.  For Camera A only, the left hand returns to holding the zoom ring on the lens.  Camera B does not require step 2.

Photo 4A Camera A Step 3

Photo 4B camera B Step 3

Photo 4A, Photo 4B      Step 3. On both cameras the right thumb now moves down to the 4 way controller and directs the AF area to the required location. The action is essentially the same in each case. However you can see in the photos  that with Camera A, the right hand  has to drop away from the right side of the camera while with Camera B, the right index finger can stay on or very close to the shutter button and close to the right side of the camera. This and the continuing hold with the left hand,  allow the user of Camera B to maintain a more secure grip on the camera during the task.

Finish. To complete the task both cameras return to capture readiness with a half press on the shutter button.

Summary. Shifting active AF area on Camera B requires fewer actions, each action is less complex, and the camera is held more securely throughout the task.   In consequence, I find that I shift the AF area on Camera B frequently but do so rarely on Camera A.   

Comment  The ability to quickly move the active AF area is particularly handy in several photographic situations. For instance if one's subject is a person  one wants the  face to be in precise focus. This will rarely be in the centre of the frame.  One solution is to focus/ lock with the centre area then  recompose. But with most cameras this will lock exposure also, resulting in the risk of incorrect exposure.

Although one of these cameras is better than the other,  neither provides a very efficient method of moving AF area. A correctly positioned and configured  JOG lever would do the job much more quickly.