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| Finishing in style (Lumix FZ1000) |
My proposed approach to scoring a camera’s ergonomics is based on evaluation of:
* Number and complexity of actions required to operate the camera.
* Holding
* Viewing
* Haptics.
The following specification list is designed to assist evaluation by working systematically through the Phases of use, identifying and making explicit the ergonomic requirements at each Phase.
All evaluation systems have underlying assumptions. In this case some of these are:
* The camera is designed to be suitable for the expert/enthusiast user who wishes to take control of the process of picture making. Novices/snapshooters can use this camera perfectly well by setting auto mode and leaving menus, buttons etc at default settings.
* In the 20th Century if you wanted to make pictures a camera was required. There were two main groups of camera users.
Snapshooters used a compact, enthusiasts used a SLR (later DSLR).
Now snapshooters use smart phones. Photography enthusiasts use cameras.
Therefore all cameras should be fully specified and configured for expert/enthusiast users.
A Proper Camera is envisaged. This has an anatomical built in handle (by which I mean one which is shaped to fit the hand which holds it), a built in EVF of high quality, a fully articulated monitor, built in flash unit, ability to fit accessory flash units, zoom lens or ability to mount one, responsive performance and good enough picture quality for most users and uses.
Maximum score allocations: This represents a judgement call about which aspects of camera use are the most ergonomically important. Obviously this is contestable but I think it is reasonable to allocate the highest priority to the process of operating the camera in Capture Phase. The actual numbers are somewhat arbitrary as they must be but they can be adjusted in the light of ongoing experience, should that be necessary.
Phase of use | Maximum score | |
Setup | 15 | |
Prepare | 15 | |
Capture | Holding | 20 |
Viewing | 20 | |
Operating | 25 | |
Review | 5 | |
Total | 100 |
All cameras are evaluated using the same ergonomic specifications, schedules and criteria. Only by this means will the better performers be distinguished from the also rans.
Price is not scored. Well implemented control systems cost no more to make than poorly implemented ones.
Summary of abbreviations used:
UI = User Interface. Can be hard (buttons, dials etc) or soft (screen based).
UIM = User Interface Module. Refers to a button, dial, lever, switch collar, ring etc.
Set and See module. This is usually a dial, lever or switch. It has manufacturer predetermined function represented by permanently marked icons, numbers, words, etc. marked on the module. You set and see the selected parameter right on the dial. Repeater readouts of the set parameters might or might not be presented in the EVF/monitor.
Scoring In each subsection the maximum score will be gained if a camera allows the user to efficiently perform all the tasks , has all the hardware and positive factors with none of the negative factors. Total maximum score is 100.
At first sight this schedule of specifications might appear quite daunting. It is certainly true that evaluating and scoring ergonomics is conceptually complex requiring a substantial investment of time and study both for the creator (me) and readers wishing to understand the process.
I have been working with the schedule for a year and have used it to evaluate and score 14 cameras (real ones, not mockups). I have found that with familiarity and practice I am readily able to use the process to produce useful results.
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| Here is a hand in the natural half closed relaxed posture ready to take hold of a Canon Powershot SX60 camera. |
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| And here is the same hand holding the camera. No change to the natural posture of the hand is required. This camera has a very nicely shaped 'inverted L' type handle which is ideal for strong, comfortable holding. The thumb support allows the thumb to angle nicely across the back of the camera. |
The evaluation specifications and schedule:
Setup Phase [Max score 15]
Tasks Make Main Menu selections, Allocate My Menu items, Allocate Quick Menu items, Select Function Button and dial assignments, set up Custom Modes, set up other functions such as Wi-Fi.
Elements Has a Main Menu, My Menu with user selected items and a separately accessed Quick Menu with user selected items for Prepare Phase selections.
Most UIM's enable user selected function.
Content Menu headings and subheadings are logical, coherent, systematic and easy to navigate. Like items are grouped together.
User interface All items are clear, legible and easy to read. The process navigate>identify>select is easily learned and becomes second nature.
Negatives Main Menu confusing, contains mystery icons or items, not logically designed, like items scattered about in different submenus. No My Menu. No Q Menu or items not user selectable. No Custom Modes. Navigation complex or confusing. Setup Phase UIM's located where Capture Phase UIM's need to be.
Prepare Phase [Max score 15]
Tasks Set Main Mode, set frequently used modes (usually Focus , Autofocus, Drive), set less frequently used modes and other adjustments required in the minutes prior to Capture Phase.
Hardware Has dedicated set and see UIM's for the most commonly used Modes. Allows quick access to other modes and functions required in Prepare Phase, by Quick Menu button, Function buttons or other quick access portal(s) on body and lens.
User interface Clear graphics, icons and displays on monitor and EVF when navigating and selecting items via Q Menu, Function buttons or other portal. UIM's for Prepare Phase do not displace UIM's for Capture Phase from top value locations on the body.
Content Quick access portals allow adjustment of other modes and functions, for instance flash, metering, recording quality, image size, ISO (if set in Prepare Phase) shutter type, image stabiliser, display, burst/continuous rate, electronic level, electronic shutter, grid lines, histogram ...............and many more, as user selected.
Negatives Any Prepare Phase items only accessible via main menu. Settings locked while camera is writing files to the memory card. Q Menu items, functions of buttons and other UIM's not user assignable. Prepare Phase UIM's located where Capture Phase UIM's need to be.
Capture Phase [Max score 65]
Holding [Subscore 20]
Tasks Hold the camera in a relaxed but secure grip with both hands with right index finger on the shutter button in relaxed position. Maintain this grip while carrying out the "operating" tasks below.
Hardware Built in ergonomic anatomical handle, inverted L type canted back 10 degrees is optimal. Ergonomic thumb support. Diagonal type is optimal. Optimal shutter button position is forward, top left on the handle (as viewed by the user).
User Experience Handle and thumb support work together to allow the user's right hand to adopt the half closed relaxed posture in basic hold position. Shutter button location enables this optimal holding posture.
Negatives Absent or poorly shaped handle. Handle only available as accessory. Thumb support inadequate in position, elevation or orientation. Sub optimal placement of shutter button.
Viewing [Subscore 20]
Tasks the operator can comfortably and clearly, in all conditions, view in the EVF or monitor the information listed below.
* Subject preview (live view) unobscured by overlays.
* Major camera data, displayed outside the preview image, in either landscape or portrait orientation, optimally below but possibly also above:
Aperture, Shutter Speed, ISO, Exposure Compensation, White Balance, Battery Status, Capture Mode in use, Remaining exposures on card.
* Secondary camera data/displays, superimposed over the preview image:
Active AF Area position and size/shape, Grid lines, Histogram, Manual Focus Guide indications, others as user selected.
Hardware There is a built in high quality EVF with high quality viewfinder optics and comfortable eyecup. There is a high quality monitor. Fully articulated type is optimal.
Content EVF and monitor gain up or down to represent exposure compensation. 100% accurate preview is provided.
User Experience EVF and monitor both provide the same information presented in the same way. There is a seamless segue from one to the other. Look in the viewfinder, see the viewfinder; look at the monitor, see the monitor. Optimally there is no perceptible EVF or monitor blackout time after each exposure.
Negatives EVF not built in, Camera data is only available superimposed over the preview image, EVF refresh rate slow, EVF delivers poor viewing quality in some conditions. Monitor fixed or only swing up/down.
Operating [Subscore 25]
Task list While continuously looking through the EVF (or monitor, but the EVF is a more stringent test) and without shifting grip on the camera with either hand, Capture Phase requires that the following tasks be carried out smoothly and efficiently, without impeding the capture process. Obviously not every exposure requires every one of these tasks to be performed but the camera should be configured so it is possible to do so:
* Adjust primary exposure parameters: Aperture (f stop), Exposure Time (Shutter speed), Sensitivity (ISO).
* Adjust secondary exposure parameters: Exposure Compensation, Program Shift, AE Lock, White Balance.
* Adjust primary framing and focus parameters: Zoom, Initiate/Lock autofocus, Manual Focus.
* Adjust secondary focus parameters: Change position and size of active AF area, manual over ride focus, AF Lock.
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| Unfortunately almost everything else about the SX60 is poorly designed. The 4 Way module is flat and flush with the rear face of the control panel, making it almost unusable. This photo shows some blobs of epoxy resin on the control surfaces allowing me to find the module by feel, with some difficulty. The optimal shape for the 4Way controller is a 'rocking saucer' with raised, sharpish edges which can be located easily by feel. |
Which way is Value Up ? When operating a camera the user has to adjust the values of many parameters such as aperture, shutter speed, ISO sensitivity, exposure compensation and zoom position.
It is most helpful if all the wheels, dials, rings, levers or other controls move the same way for value up of each parameter and the opposite way for value down.
Hardware There are sufficient UIM's of appropriate design on body and lens with which to drive the camera as described in the task list. UIM's on the lens controlling zoom, focus and aperture (if fitted) are of circumferential type. UIM's on the body can be operated by the right index finger and thumb without having to shift grip.
User experience With practice the user can learn to drive the camera like a motor car. The user looks through the viewfinder (windscreen) at the subject (traffic ahead) and operates the device by feel without looking at it. With further practice the user does not have to think about the process of operating the camera any more than a driver thinks about operating a motor car.
Negatives The camera is configured so the user has to interrupt the capture process in order to change one of the parameters listed above. UIM's for Capture Phase are located in a physical position lower in the ergonomic hierarchy than UIM's for Setup, Prepare or Review Phase. The user has to enter a menu or shift grip or take the eye away from the viewfinder to adjust on of the parameters in the task list.
Review Phase [Subscore 5]
Task list Tasks which photographers might want to perform in Review Phase may vary greatly according to individual preference. Some photographers do little in camera review, others a lot. Ergonomically this is the least critical phase of use as the photo has already been captured. As a minimum I would list:
* Recall the last 1-9 photos captured and select one.
* Zoom into and move around in a review image.
* Jump from one image to the next or previous at the same level of magnification and the same location in the frame.
* Delete one/many.
Hardware The camera needs UIM's to enable the tasks above to be performed. These need to be located low in the positional hierarchy on the camera.
Content Comprehensive data about each image is available and efficiently recalled onto the monitor screen or in the EVF in the same form.
User experience The task list can be carried out efficiently.
Negatives Essential file data is not able to be recalled. It is not possible to scroll from one frame to the next at the same location and magnification. Auto review cannot be disabled. UIM's for Review Phase occupy high value locations on the camera which are better reserved for Capture Phase.
Summary
Ergonomic evaluation of a camera requires attentive observation of the actions required to operate the device.
Anybody with a will can do this. There are no technological issues here. An understanding of quantum mechanics is not required.
The ergonomic assessment has three essential elements:
* Schedule and Process This means understanding what the specifications and schedule mean and working through the assessment process guided by the schedule framework.
* Narrative This is a description of how well a camera performs against each specification with comment on effective and ineffective aspects of design and implementation.
* Score The subscores and final score provide a convenient means of comparing cameras. The scores are only useful if complemented by an understanding of the process and narrative.
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