Ergonomics in a Nutshell

CAMERA  ERGONOMICS

Summary of findings

Author  AndrewS

Reference  This article is a summary of my previous posts on this blog, titled Camera Ergonomics Parts 1-12.

Definitions    Ergonomics is defined by Wikipedia as "the study of designing equipment and devices that fit the human body, it's movements and it's cognitive abilities".   Taxonomy  according to the Macquarie Dictionary is  "a classification....in relation to.. ..principles or laws".   Kludge or kluge has been variously defined but for present purposes I  use that attributed to J W Granholm,  "an ill assorted collection of poorly matching parts forming a distressing whole".

History  For most of the 20th century the shape of cameras was largely determined by mechanical constraints of the type, for instance rangefinder, single lens reflex, twin lens reflex  etc... The 21st century has seen  the invention of the mirrorless interchangeable lens camera, fully electronic operation and modern fabrication technology.  These developments allow designers to make cameras just about any shape at all and to place control modules anywhere on the device.  One might have expected this freedom to make the camera designers' job easier but paradoxically it appears to have had the opposite effect. An electronic camera intended to be controlled by a practiced user is extremely complex. This combination of freedom and complexity forces camera designers to make a host of decisions which were simply not required in former times.

Photo 1 Size Comparison

Current offerings    Perusal of cameras currently on the market reveals the different ways in which  makers are trying to respond to this challenge while simultaneously satisfying the demands of their engineering, finance and marketing departments.  My hands on assessment of many current DSLR's and mirrorless interchangeable lens cameras (MILC) is that their ergonomic development  is lagging behind image quality, features and performance. Many are kludges, in desperate need of ergonomic redesign.

Describing ergonomics   I note, when reading amateur and professional cameras reviews that there appears to be a poverty of description about ergonomic issues. Contrast this, for instance to the mind boggling plethora of descriptions in minute, pixel peeping detail of image quality.  I believe this is due to a paucity of  language, taxonomy and understanding of the essential elements of camera ergonomics.

My mission  in producing this blog is to report the results of my research into camera ergonomics, develop a systematic description of ergonomics separate from  anyone's  likes wants or preferences, increase consumer awareness and understanding of ergonomics, encourage informed consumer feedback to manufacturers and eventually, I hope, enjoy the results in the form of cameras which are a pleasure to use.

Photo 2 Rear Layout

Basic principles

* Form follows function.  An electronic camera designed this way will have it's own style not derivative of anything else and will appeal because it is enjoyable to use not because it looks like a shrunken pro DSLR or somebody's favourite film camera from the 1980's.

* Layout follows fingers. Technology changes but our hands and fingers stay the same. The starting point for the shape and layout of any camera should be the functional anatomy of the human hand and fingers. The shape of the right side of the camera should be crafted to fit into the hand in the "half closed, relaxed" position described in Part 4 of the Camera Ergonomics series on this blog. This is how the shape of the mockups was developed.

* There are four phases of camera use, Setup, Prepare, Capture and  Review.  Each phase presents a set of tasks to be completed. Each phase is subject to time constraints, some acute, some relaxed.

* In the Capture Phase there are three main task groups, Holding, Viewing and Operating.

* There is a hierarchy of camera real estate locations, High, Medium and Low priority.  Actions required to carry out the tasks of the Capture Phase are allocated to High priority locations.

* Holding requires optimal design for the handle and thumb rest. After much trial and error, I discovered the parallel handle type provides the best grip for MILC's with compact body size.

* Viewing is optimised by the location and design of  user interface modules, monitor and viewfinder.

* Operating is optimised by  type and location of user interface modules.  Good ergonomic design clearly identifies which modules are used for each of the phases of use and which real estate location works best for each.

* There are primary, secondary and tertiary exposure and focussing variables. It is essential to explicitly rank by urgency level the tasks required to adjust each. This will help determine what type of user interface module works best and where it should be located.

* All user interface modules on an electronic camera should be capable of extensive user configuration. There are hundreds of variable parameters and therefore thousands of potential combinations available. Each practiced user will have his or her own preferred way of interacting with camera controls and this will change with time, experience or different circumstances.  It is totally unacceptable for manufacturers to allocate one set function to each interface module of an electronic camera.

Photo 3 Top Layout

Mockups  The best way to experiment with the holding and operating aspects of camera design is to make physical mockups. These can be built, rebuilt, pulled apart, remodelled and reconfigured without restraint until they "....fit the human body and it's movements..." extremely well.

These days the only immutable elements in the size/shape equation for any camera are the diameter of the lens mount and the flange back distance.  DSLR's have a flange back distance  in the 40-45 mm range. MILC's are about half that, in the 17.5 - 25.5 mm range. This is the main determinant of  body depth. The rest is, or in my view should be,  determined by ergonomic factors. Obviously the engineers will have a major contribution. However with the NEX series,  the engineers at Sony have shown they can cram all the essential electromechanical components into bodies which are incredibly compact, arguably too small for comfortable handling.

Photo 4 Natural Hold

Determinants of camera body size/shape

Width:  On the front, lens mount diameter, inset of the lens axis from the left side (as viewed by the operator), handle width and design.

On the back, monitor width, rear control panel width and thumbrest design.

Height: On the front, body shape design (SLR style vs RF style) handle design, shutter button height.

On the back, monitor height, viewfinder height.

The mockup used to illustrate this article has the following dimensions:  Width 142 mm, Height 90 mm, Depth 67 mm. It has exactly the same height and slightly less depth than  a Panasonic GH2 and fits easily into the same compartment in a camera bag. Yet it offers vastly improved ergonomics with a much larger, more anatomically shaped handle and thumb rest, hugely improved layout, much larger top and rear control panels, much larger interface modules much more easily located by feel and a better positioned viewfinder. It also has a larger area allocated to the monitor.  This size camera would be very suitable for an expert/pro style micro four thirds or APS-C  MILC.

The photographic sequence, Setup to Capture and Review.

This sequence assumes a camera designed to be controlled by a practiced, enthusiast/expert user. Snapshooters can make good use of the holding and viewing benefits of an ergonomically designed camera while working with the reduced interface module set available when the main shooting mode dial is set to one of the fully auto modes. In this case, some of the interface modules are disabled and a simplified user experience is provided. All menus and modules have maker assigned default settings for the novice or snapshooter intimidated by the overchoice which is inevitable with a multiconfigurable electronic camera.

Please refer to  Part 11 of the series for a summary of a typical task list in each of the four phases of use.  The text below refers to the photos which accompany this article.

Setup Phase   Setup usually involves delving into menus, with little time pressure. Menu access is allocated to user interface modules, in this case buttons, in a low priority area of the camera body. Navigation can be allocated to the JOG lever, by up/down. left/right movements and selection by pressing the same module inwards. One of the blue buttons accesses the complete main menu, the second blue button opens a user configured "my menu", for more frequently used items.

Prepare Phase  This refers to the period of a few minutes during which camera settings are adjusted to give best performance with  the current photographic assignment. This might be landscape, macro, action, group with flash etc... each requiring a different combination of operating settings.

On the top control panel there are four "set and see" modules, two dials, two levers, which control Main Shooting Mode, Drive Mode, AF/MF Mode and AF Area. This arrangement is ergonomically efficient as each of these parameters can be checked at a glance and quickly adjusted. The actual functions available at each station can be user configured in the main menu in Setup Phase.

On the rear control panel there is a set of buttons in the medium priority zone, all user configurable from every function available to the camera. Each button brings up a parameter. The JOG lever scrolls around options then selects with a push.

Photo 5 Operate JOG lever

Capture Phase  In this phase the ergonomic demand eaches a peak. No longer can the user hold the camera away from the body and make adjustments essentially at leisure. The concept which has guided my design for Capture Phase is as follows:

The camera is designed to be driven like a sports car by a practiced user. In a sports car the practiced driver does not have to think about or pay conscious attention to steering, pressing the clutch and shifting the stick to change gears or pushing the brake pedal to slow down. He, sometimes she, just does the action while concentrating on the road ahead. 

So the actions required by a photographer to complete the task list in the Capture Phase should be carried out in a time frame of a few seconds:  

* While looking continuously at the subject through the viewfinder (or monitor, but the viewfinder provides the more critical test as all adjustments must be carried out by feel)

* While holding the camera firmly and comfortably with both hands and without having to change or shift grip with either hand

* Using the left hand for zoom and manual focus

* Using the right index finger for primary and secondary exposure variables (See Part 5) and capture

* Using the right thumb for primary and secondary focussing variables (Part 5) with minimal disruption of the basic grip.

The video user can nominate an interface module to start/stop and other modules to configure video parameters.  Under no circumstance should a camera maker allocate video start to just one button. Video users might prefer to use a different module (button or other device).  Those who shoot stills will want the option to use that module for another purpose.

Review Phase  The task list in this phase varies markedly from one user to the next.  Some people like to review every exposure, others don't bother.  Review can be set to start automatically or on activating a user selected module (usually a button) in a low priority zone on the camera. Navigation and image magnification is with the JOG lever. Left/right, up/down to navigate, push- push to enlarge. Module behaviour can be configured to personal preference in the main menu.