This is a summary of the scoring schedules.
For further discussion of the rationale behind the schedules see the Major Summary here.
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 |
Scoring In each subsection the maximum score will be gained if a camera allows the user to efficiently perform all the tasks with a small number of actions each of low complexity, has all the hardware and positive factors with none of the negative factors. Total maximum score is 100.
I rate all cameras against all other cameras using the same criteria. There is no division into entry, midrange, professional or any other grouping. I expect all cameras for all users to have excellent ergonomics.
The overall score has three elements:
1. Subscores.
2. A narrative explaining the scorer’s reasoning for the subscore with reference to the criteria.
3. A total score.
Some aspects of scoring rely on subjective impressions, for instance whether a handle is rated as ‘comfortable’. In this case long term experience with many cameras helps to inform the decision process.
But many items on the scoring schedule involve rating the camera against objective criteria. For instance can all the tasks of Capture Phase be carried out while looking through the viewfinder and without having to change grip with either hand ?
Unscored features
Modern cameras come with a plethora of features and functions such as ‘art filters’, special effects, scene modes …..etcetera. I do not include these in the ergonomic evaluation or score.
I also do not rate touch screen capability. Some users say they have high regard for this feature but from an ergonomic perspective it is unusable with hand held operation and OVF/EVF viewing. It may be useful with the camera on a tripod for stills or video but cameras designed for stills or hybrid still/video (like the Panasonic GH4) will still work just fine without the touch screen. Some dedicated video cameras rely heavily on a touch screen interface.
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.
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. Q Menu 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. Clearly not all these tasks are required for every shooting session but the camera should enable them for the times when they are required.
Hardware Has dedicated set and see (module with inscriptions indicating current setting) UIM's (user interface modules: covers buttons, dials, switches, levers etc) 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 blackout time after each exposure.
Negatives EVF not built in or not available, 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.
Which way is Value Up ? When operating a camera the user has to adjust the value of several parameters such as aperture, shutter speed, ISO sensitivity, exposure compensation and zoom position.
It is very helpful if the direction of movement of each dial, wheel, ring, lever or other control is the same for value up with each parameter and the opposite for value down.
Haptics Each user interface module (button, dial, lever, switch etc) must be designed with attention to detail so the module is easy to locate and operate by feel if required in Capture Phase of use. This includes all aspects of the position, elevation, configuration, size, shape, texture and feel of each module. Individual modules should be easily distinguished from each other by feel.
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, change grip with either hand or lower the camera from the eye in order to change one or more of the parameters listed above. Poor/suboptimal UIM location or haptics.
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.
Subscores-vs-Overall Scores
Sometimes a camera which I so dislike using that I will mostly avoid it reaches a higher overall score than one which I will and do use. For instance the Canon SX60 scored 56 overall which is higher than the Panasonic LX100 score of 53.
I will and do use the LX100 but avoid the SX60. That is partly due to the image quality difference which is heavily in favour of the LX100. But it is also partly because the SX60 rates decently well on the Setup, Prepare, Holding and Viewing subscores, which keep the overall score up, but it falls down on the Operating score which is critical to the user experience.
Further reading
On the ‘Pages’ bar of this blog, found at the top of the home page in most browsers, there is extensive discussion about many topics grouped under the ‘Basic Concepts’, ‘Design’ and ‘Measuring Ergonomics’ tabs.
Each of the specific camera reviews also has commentary about ergonomic issues.
End of this post
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