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Friday, 9 January 2015

Measuring Camera Ergonomics Part 3 Scoring Schedule (revised and reposted)


LX100

Summary of abbreviations used:

FLC = Fixed Lens Camera.  FZLC = Fixed zoom lens camera.

ILC = Interchangeable Lens Camera.

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.
I rate changing lenses as just about the most ergonomically disruptive task which any camera user has to carry out.
So in the interests of  reasonable comparison, the score for an ILC assumes the fitted lens remains in place.

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.  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.
For ILC only: Mount an appropriate lens. I have not included this task in the scoring schedule. It is a task which must always be carried out with an ILC (unless just one lens is always left mounted on the body) and is never required for a FLC.
Scoring an ILC assumes the lens is not changed in order to achieve realistic comparison between ILCs and FLCs.  

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 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, 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.

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.

Haptics   All user interface modules are designed with great care to detail so as to ensure that those required to be located and operated by feel can be thus used. No control modules are prone to accidental activation. All dials and similar modules are easy to locate and operate by feel. Control modules can easily be distinguished from each other by feel. 

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.

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