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Toilet as architecture

In the following comparisons, I will use two cameras, the Panasonic GH3 representing the Modern layout and the Fuji X-T1 representing the hybrid/traditional layout.

Heading the previous post is a photo of a small kestrel in flight. At the moment this little raptor glided over my head I had been about to make landscape photos with a telephoto zoom lens. The camera was set to Aperture Priority Mode. My Task was to switch from Aperture Priority auto exposure to Shutter Priority auto exposure and set a shutter speed of 1/1000 sec, which my previous experience had informed me is about right for birds in flight. Completion of the task requires actions.

Panasonic GH3

 
GH3: With this camera I was able to carry out the required actions while continuing to look through the viewfinder. The actions are

* Shift grip with right hand to apply right thumb and index finger to the Mode Dial.

* Turn Mode Dial one notch from A to S. See confirmation of setting in viewfinder. I had previously set the shutter speed to 1/1000 sec so this was automatically recalled.

* Return right hand to normal operating position and take the picture.

Fuji X-T1. Photo courtesy of Digital Photography Review  dpreview.com Some people have said they really like this camera but as Michael Reichmann said on his Luminous Landscape site "be careful what you wish for".

X-T1: I guess with a lot of practice an experienced user might be able to perform the required actions while looking through the viewfinder but I suspect most will lower the camera so they can see what they are doing. Actions required depend on the lens mounted. The Fuji X lens system is a bit complicated. Some lenses (mostly primes) have a clicking aperture ring with marked stops, some (generally variable aperture zooms) have an aperture ring with no marked stops and a third type (budget models) have no aperture ring at all. Let's assume we have a variable aperture zoom with an aperture ring. The required actions are:

* Release grip on the camera/lens with the left hand.

* With the left hand, locate the little slider switch on the upper left side (as viewed by the user) of the lens barrel and move this to the red A position.

* Take the weight of the camera/lens with the left hand, shift grip with the right hand and move the right index finger and thumb onto the Shutter Speed Dial.

* Turn the dial off the red A position around to 1/1000 position.

* Return the right hand to normal operating position.

* Return the camera to eye level and take the picture.

Comment You can see that the GH3 completes this task with less actions, most of which are less complex and with fewer support actions being required.

Here is another task example: Change ISO setting.

GH3: The required actions can be carried out while looking through the viewfinder and without having to shift grip with either hand.

* Move the right index finger back from the shutter button onto the ISO button (with a little practice the ISO button is easily distinguished from the buttons on either side). Press the ISO button.

* Change ISO setting with either the front or rear control dial (depending on user selected function settings for the dials)

* Take the photo.

X-T1: It might be possible for the experienced user to complete the required actions while looking through the viewfinder but I suspect most will prefer to lower the camera to see the ISO dial.

* Release grip on the camera/lens with the left hand.

* Grip the ISO dial with the index finger and thumb of the left hand and turn the dial to the required setting.

* Return left hand to the normal holding position.

* Take the photo.

Comment Again you can see the modern UI allows the task to be completed with less actions, most of them less complex, with fewer support actions required.

I could go on for ages detailing the actions required to complete each and every task of operating the camera but I suspect this would become tedious. The same result comes up every time. I think the point is made.

Conclusion A well designed modern UI allows the user to carry out the tasks of operating a camera more quickly and efficiently than is possible with a hybrid traditional UI.

By the way.... The Fuji X-T1 is one of the more coherently designed cameras with hybrid traditional UI. Some are much worse to the point of being ergonomically chaotic. Check out the Nikon Df.................This thing is like an ergonomic train wreck with miscellaneous cluttered user interface modules scattered about incoherently. Some have functions which operate at odds with others. Very strange...............

Kestrel. Panasonic GH3, 100-300mm lens. I was getting ready to make some long distance landscapes with the Mode Dial on A (perture priority). This kestrel hove into view so while continuing to look through the viewfinder, I quickly flicked the dial to S (hutter priority) which was pre set to 1/1000 sec and made 5 quick shots in the 3 or 4 seconds the bird was within range.

Nostalgia vs Efficiency ?

For a large part of the 20th Century if you had an SLR or rangefinder it came with the traditional suite of controls because there was no alternative. Cameras were mechanical. The means by which shutter speed, aperture and focus were achieved were all mechanical and the settings all visible from above the camera. In due course cameras acquired more and more electronic functions. Aperture and shutter speed repeater readouts appeared in the viewfinder. Aperture Priority then Shutter Priority Auto exposure became possible. Around the turn of the century control of auto exposure capabilities was consolidated to a single (set and see) Mode Dial with adjustments made by a mode dependent control dial. This is the basis of the modern control system which still dominates the world of DSLR's and most MILC's.

The retro phenomenon Over the last few years we have seen several new camera models released with some variant of the traditional control system, always as a hybrid with the designers trying to blend traditional and electronic controls in the one device. My work with ergonomics leads me to the view that the retro phenomenon is actually retrograde and leads to a less efficient user experience than a well designed fully modern control layout can provide.

Basic features of the traditional user interface All the user interface modules (UIM's) are of set and see type. This means what it says. The dial or lens ring has marked settings which are selected directly. An example of an all manual 1960's/70's traditional camera is the Pentax Spotmatic shown in the photo.

Advantages of the traditional UI

* Settings for primary and in some cases secondary exposure and focus parameters can be set and are visible from above the camera, without needing to turn it on and without needing to look through the viewfinder or monitor or LCD panel.

* Some users have expressed in user forums a preference for setting and viewing exposure and focus parameters on set and see dials as they say it forces them to think more carefully about their "firing solution" (ISO/Shutter Speed/Aperture) than is the case with a modern UI using a Mode Dial and Control Dial.

* Some users say they "like" the style, appearance or idea of a traditional camera. I say beware the pervasive influence of "likes", any one of which is likely to be idiosyncratic and temporary.

Disadvantages of the traditional UI

* In Capture Phase of use, when one is looking through the viewfinder, all those set and see dials are invisible. But Capture Phase is precisely when you most need to see readouts for primary and secondary exposure and focus parameters. So the makers have to provide repeater readouts for all that camera data in the viewfinder.

* So now we have a key camera data set appearing in two places. But there is a considerable opportunity cost to this. A set and see UIM can only be used for one data set. If the module is used for, say, ISO setting, it cannot be used for anything else. My ergonomic studies have led me to realise than set and see UIM's are actually most useful for Prepare Phase adjustments to the most frequently used Modes. Individual preferences vary but these would I think usually be

* Focus Mode (AFS/AFC/MF)

* Autofocus Mode (On Panasonic cameras, Face detect/Tracking/1-Area/23-Area/Pinpoint)

* Drive Mode (On Panasonic cameras, Single shot/Burst/AE Bracketing/Timer delay)

So these should have highest priority for location on camera top set and see dials. But if primary exposure parameters are on those dials the modes have to be bumped off to a Q Menu or in some cases to sub levers beneath the top dials. This can make the top deck a very busy place, not easy to read or operate manually.

* Without a Main Mode Dial you cannot have a Novice's (point and shoot) mode or Custom modes.

* There is no direct access to P,A,S, auto exposure or Manual exposure settings.

* My time and motion studies of the actions required to operate the camera in Capture Phase show that in most cases the traditional UI requires more actions each of greater complexity than is the case with a modern style UI.


Advantages of the modern UI
* Permits a cleaner layout with less UIMs required than the traditional style.

* Permits direct access to capture modes including a novice (point and shoot) mode and custom modes.

* Gives direct access to the P,A,S, auto exposure modes and manual exposure mode.

* Almost all actions required to operate the camera are carried out with fewer, less complex movements of the fingers and hands and fewer associated movements are required to enable the primary movements.

* There can be more space on the camera for UIMs the function of which can be user set. Fewer UIM's have only one function. This allows each user to effectively design their own interface.


Disadvantages of the modern UI
* I really can't think of any. The operator cannot see readouts for aperture, shutter speed and ISO without looking in the viewfinder or monitor but I don't see that as a disadvantage. That is where and when you need to see that particular data.

* Some people have expressed the idea that the modern camera looks like a lump of plastic without a "soul". Maybe it doesn't look retro chic funky cool. The top deck is not loaded with "real metal" dials. So what I say, it works better.


Next: Worked examples

　

　

　

Coastal Scene. Panasonic GH3 with 12-35mm f2.8 lens.

 

Location of the shutter button is of crucial importance to the overall functional design of a camera.

There are basically two options,

1. Shutter button rearward, located on top of the camera body. This is the classic traditional camera location, used by millions of film SLR's and rangefinders throughout the mid part of the 20th century. There has been a recent and in my view ergonomically retrograde trend for new camera designs to reprise this shutter button position.

2. Shutter button forward, located on the handle. This has been the standard SLR/DSLR shutter button position since the Canon T90 of 1984.

Why it matters The shutter button is universally operated by the pad of the distal phalanx of the right index finger. Therefore, obviously, the index finger has to go where the shutter button is located and the rest of the hand is connected to the index finger and also to all the other fingers so the position of the shutter button directly controls the possible positions of the right hand and all the fingers. This has major ergonomic and functional consequences.

Functional anatomy Human hands vary in length, width and thickness but reasonably healthy ones all work the same way. The starting point is the half closed relaxed posture as shown in the photo. In this position the hand is ready for action. Hardly any muscle effort at all is required to take up this position. A well designed camera should have a handle and body shape and shutter button position which:

* Allows the right hand to adopt the half closed relaxed posture while holding the camera ready for action. The hand is ready for action and so is the camera.

* Allows the index finger will fall naturally onto the shutter button without strain.

* Locates high value user interface modules (UIM's, buttons, dials etc) adjacent to the shutter button such that they can be operated using the index finger without having to move any other finger. Most cameras fail to meet this requirement, which is disappointing as it is actually quite easy to achieve with good design.

This is the approximate position of the hand and fingers holding a camera with top/rear shutter button position. It's not the worst thing in the world and young people with  flexible joints might be happy with it. But compared to the grip below this one is less natural and comfortable and provides less options for operating user interface modules other than the shutter button.

Hand position with top/rear located shutter button The photo illustrates the position which the right hand must adopt when holding a camera with rearward shutter button position. You will notice this is not the half closed relaxed position. The index and third fingers have been pulled apart into an unrelaxed, joint stretching position.


Benefits of a well designed shutter button forward position
* Relaxed yet strong basic hand/finger posture.

* Shutter button can be (but in actual camera is often not) located exactly where the index finger wants to find it.

* Handle can be designed to wrap over the third finger so the camera can be supported without the need to tense gripping muscles.

* Allows UIM's, particularly a control dial adjacent to the shutter button to be reached and activated by the index finger with no movement by any other finger.

* Right side neck strap lug fits between index finger and thumb, does not intrude on holding.

This is the half closed relaxed posture. A camera with forward shutter button can be designed so it fits into this hand/finger position (not the other way around) This is more relaxed, comfortable and strong than the position above. The index finger has more freedom of movement to operate UIM's other than the shutter button.

Disadvantages of shutter button forward position

I can't think of any. You do need a handle on which to locate the button but that is an ergonomic advantage not a disadvantage.

Benefits of shutter button top/rear position

I can't think of any. Really. None. Old style 20th Century cameras had the shutter button there because it connected mechanically with a mechanism beneath the button. Manufacturing technologies of the day did not permit a different location. Today the connections inside the camera are electronic and the shutter button could literally be anywhere on or off (remote release) the body. I have no idea why the makers of some new cameras stick the shutter button on top of the body. Nostalgia ?? Reprise the good old days ?? ???


Disadvantages of the top/rear shutter button position
* A full ergonomic handle cannot be incorporated into the design. Only a reduced handle can be fitted due to the position of the fingers. This cannot incorporate an overhang beneath which the third finger could fit. In consequence the right hand has to grip the camera by force of muscle. If the hand relaxes the camera will fall immediately.

* It is difficult to find an appropriate location for a front control dial. Cameras with top/rear shutter button and a front dial usually position the dial on the front face of the body, beneath the shutter button. But in that position it cannot be operated by the index finger without shifting grip with all the fingers of the right hand. Some makers locate the dial like a collar around the shutter button. This is more accessible but captures all the real estate around the shutter button leaving no space for other high value UIM's.

* The basic hold position with top/rear shutter button is less comfortable than that used with a well designed forward shutter button position.

* On many cameras which I have used the right side strap lug manages to dig itself into some part of my right hand, usually the pad over the base of the index finger. In addition there is no clear space where the strap itself can drape while the camera is in Capture Phase.

Shutter button position on the mockups The process by which I make mockups involves shaping the camera and all it's parts to conform to my hands and fingers. I work on the body, handle and thumb support until the resulting shape feels comfortable in my hands. I do not draw the shape. I start with blocks of roughly cut wood then cut, file sand and often fill them until the shape is right. Then after that I put the shutter button exactly where my index finger wants to find it. On none of the full featured cameras did the shutter button end up in the top/rear position. My only mockup with top/rear shutter button is the compact. In that case constraints of the very small size forced the shutter button onto the top of the body. A very small mini handle is fitted. This works but is not as comfortable as the larger models.

Summary There is no functional or ergonomic rationale for the top/rear shutter button position on any camera larger than a small compact.

Recent cameras with top/rear shutter button location The Nikon Df, all the Fuji X-Cams, Sony A7/R, Panasonic GX7, Olympus Pens, EM5/10 all have the top/rear shutter button location and they all have ergonomic problems as a result. It is my carefully considered and researched view that all these cameras are headed backwards ergonomically. In my view one of the few things Canon has gotten right in recent times is a steadfast commitment to the shutter forward configuration on it's DSLR's. Of course I think many of those DSLR's should be MILC's but that is another story.

　

　

 

I posted a piece on this recently. Here is a summary :

Holding You would not think that the two would be any different to hold. Indeed if both are fitted with a full anatomical handle there is no difference. However all the actual flat top cameras in my experience also have the shutter button in rearward position, on top of the body. This makes provision of a full handle impossible. I will discuss this further in the next post. So considering actual cameras in production, hump tops with full handles are more comfortable and secure to hold.

Both mockups are the same size. On the left the flat top, on the right the hump top. Even with it's decent anatomical handle the flat top has less real estate for stuff. The inbuilt flash and EVF are squeezed into the same horizontal space. There is room only for one set and see dial.

Viewing Flat tops have the viewfinder top left. Humptops have the viewfinder on the lens axis, closer to the midline of the camera. For right eye viewers one might think the flat top would be preferable. In practice however, with actual cameras, I have not found this to be necessarily the case. I am a natural left eye viewer but have trained myself to use the right eye so I can appreciate the requirements of both. With the Panasonic GX7 and Fuji X-E1 I found myself squinting more than I would with any hump top camera. This was due to stray light entering the viewfinder area to a significantly greater extent than occurs with hump tops.

With left eye viewing both types can be awkward, in both landscape or portrait orientation.

Overall I find a slight advantage to the hump top provided the viewfinder eyepiece extends rearward from the face of the monitor by about 15mm, no less, so one does not have to twist the head sideways to see in the viewfinder.

Even in a medium size the hump top has more space for stuff.  The flat top on the right is wider than the hump top because it has a parallel handle. Even so the hump top has more space available. I squeezed two set and see dials onto the flat top but I suspect that would be a bit tight in practice. On the hump top I opted for two user configurable buttons in that location which gives more control to the user about which functions can be controlled from the camera top.

Operating The main difference between the two is the amount of real estate available on top of the body for user interface modules, EVF, hotshoe and built in flash. The hump top locates the EVF, hotshoe and built in flash fore and aft in a line. This frees up space on either side of the hump for set and see dials and other UI modules, be they dials or buttons. Some flat tops fit the built in flash in front of the EVF but this is possible only if both are small.

Some users may find an advantage in having the viewfinder on the lens axis particularly in portrait orientation where the hump top provides a more balanced hold/view position. Some users might also find the hump top hold/view position more secure and balanced with long lenses which require a high level of stability.

On balance I give this to the hump top, by a small margin, even when the viewfinder is electronic and could be located anywhere.

 

Since the advent of the smartphone camera sales have fallen heavily. Compacts have been affected most but DSLR's and MILC's are also down, at least to the end of 2013. It seems to me that if the camera as a separate device is to survive and flourish it needs to present a very different user experience from the smart phone.

The smart phone is

* largely automatic in operation. It does not engage the user much in the process of making pictures.

* Held out in front of the operator who previews the picture on the monitor.

* Not fitted with a real optical zoom lens.

* Uses touch screen controls not a comprehensive set of hard user controls.

The Proper Camera needs to provide a far more engaging experience for the user. It needs

* An anatomical handle and thumb support

* A built in EVF

* Fully articulating monitor

* Long range zoom lens (or the capacity to mount one)

* Fast, responsive performance

* Comprehensive set of hard (dials, levers. buttons) control modules suitable for the expert or enthusiast user.

* Ability to shoot RAW files

It should also have good enough picture quality although many cameras and some smart phones already have this. What I am driving at here is that the key difference between the proper camera and the smartphone lies in the level of engagement of the user. Picture quality differences are secondary in my view.

Touch screens, Wi -Fi Many cameras these days seem to be trying to offer the user features which are characteristic of smart phones. One of these is touch screens which I have found to be useless on a hand held camera with eye level viewing. I posted a detailed piece about this in June 2013. Another is Wi-Fi connection to a smart phone which could be useful as a means of remote control for the camera but less useful as a conduit for uploading files due to the large size and proprietary characteristic of many RAW files.

Fixed lens or interchangeable (ILC) My ergonomic analysis is equally applicable to cameras with fixed or interchangeable lenses. With improvements in the imaging capability of small sensors I would not be surprised if one day superzoom types supplant interchangeable lens types.

DSLR or MILC DSLR's have been undisputed rulers of the serious camera realm for many years but I believe that MILC's will become dominant in due course. I got fed up with the inaccurate focussing, overweight, oversize lenses and clunky user interface of DSLR's years ago. So my ILC's are now mirrorless and most of my ergonomic work now concentrates on MILC's.

Many cameras these days have good enough picture quality and performance for the majority of users and uses. The principal characteristic by which cameras can be distinguished from each other is ergonomics, including basic design characteristics, the user interface and user experience.

The three main descriptors of a camera are image quality, performance and ergonomics. There are many well known metrics by which image quality and performance can be measured, compared and discussed. But ergonomics lacks a system of widely understood, measurable descriptors, language and taxonomy (an organised method of classification). In consequence camera users and reviewers have difficulty talking or writing about ergonomics. If you can't name the thing you can't talk about it. If you can't measure something it is difficult to compare it with another thing.

If most modern cameras had excellent ergonomics this would not be a problem. But every camera I have used and/ or tested in the last five years could benefit from better ergonomic design. The worst are absolutely disgraceful but even the best could be improved with some attention to detail.


Taxonomy of camera ergonomics
The following description applies to a fully featured proper camera, not a low spec beginner's model. My concept of a Proper Camera requires an inbuilt electronic viewfinder, a full anatomical handle, a fully articulated monitor and a full suite of external controls for the expert/enthusiast user. Novices can leave Menus and Function buttons at default settings, turn the Main Mode Dial to the novice's fully automatic setting and use the camera as a point and shoot.

* There are four Phases of camera use, Setup, Prepare, Capture and Review.

* There are three engagement modalities, Holding, Viewing and Operating.

* There is a Task List applicable to each Phase of use.

* Completion of each Task requires one or more Actions. Actions can be counted and also evaluated for complexity.

Each Phase generates a different task list and utilises different aspects of the user interface. The task lists which follow are for basic still photo camera operation. I have not considered the requirements of video, off camera/multiple flash, time lapse and numerous specialised functions. I have also written the task lists for a mirrorless camera, with fixed or interchangeable lens. The lists are essentially the same for a DSLR but the optical viewfinder (OVF) replaces the electronic viewfinder (EVF).

Setup This is the Phase prior to setting forth to make photos. It is negotiated at leisure, probably with the Instruction Manual to hand. Typical tasks of Setup Phase include

* Make Main Menu selections.

* Allocate My Menu selections if available.

* Allocate Quick Menu items if available.

* Select Function button assignments if available.

* Select dial operation/function.

* Setup Wi-Fi and other special functions as available.

* Setup Custom Modes if available.

Some modern cameras have nice, straightforward menus which are logical and easy to negotiate. Others are frustratingly obtuse and convoluted. Some cameras allow a high degree of user configuration. This is a wonderful thing as it allows the user to effectively build his or her own user interface but novices might find the learning curve rather steep.

Prepare This Phase occurs in the few minutes before staring to make photos. Several types of user interface work well in this Phase. These include set and see dials (where you make and can see a setting on the dial), Quick Menu items and Function Button items. In each case you typically have the camera held away from the eye and are able to see dials, press buttons and scroll wheels by sight with selections and settings appearing on the monitor screen. With a modern camera using Mode Dial and Control Dial(s) layout typical tasks of this Phase are:

* Set Mode Dial to Auto, P, A, S, M, C or whatever is available.

* Set the most frequently used Modes. These would usually be Focus Mode (For instance AFS/AFC/MF) , Autofocus Mode (For instance Face detection, AF Tracking, 23- Area, 1-Area, Pinpoint) and Drive Mode (For instance Single shot, Continuous shooting, exposure Bracketing, Timer Delay). Ideally these frequently accessed Modes will be located on set and see dials/modules. This is the most efficient use of such dials or similar modules as it relates to items which you do need to adjust in Prepare Phase but do not need to adjust in Capture Phase.

* Set less frequently used Modes and other adjustments. These might include Flash Mode, Metering Mode, Recording Quality, Image Size, ISO (if it is desired to set this in Prepare Phase), Shutter type, Image stabiliser, Display, Burst/continuous rate, Electronic level, histogram.....etc....etc.   modern cameras are loaded with such items. These are best located on a programmable Quick Menu and/or programmable Function buttons.

Capture Now you are in the process of making photos. This phase imposes the highest ergonomic demand on camera and user as all adjustable parameters must be visible at a glance while using the viewfinder and quickly adjustable without having to shift grip with either hand. Tasks of this phase are:

Holding Hold the camera in a relaxed but secure grip with both hands. Maintain this grip while making the adjustments below.

Viewing Easily view in the EVF (or monitor)

*Subject preview (live view)

* Primary Camera data, ideally on a black strip beneath the subject preview (not superimposed over the preview image) in either landscape or portrait orientation. This typically would consist of Aperture, Shutter Speed, ISO, Exposure Compensation, White Balance, Battery Status, Capture Mode in use, Remaining exposure on card.

* Secondary camera data, superimposed over the preview image. This would usually consist of active AF area position and size, Grid lines, histogram, manual focus guide indications and others as available and/or desired.

Operating While continuously looking through the EVF and without shifting grip on the camera, Capture Phase requires that the following tasks be carried out quickly and efficiently, without impeding the flow of camera work. Not every exposure requires each and every one of these tasks to be performed.

* Adjust primary exposure parameters: Aperture (f stop), Exposure Time (Shutter Speed), and Sensitivity (ISO setting).

* Adjust secondary exposure parameters: Exposure Compensation, Program Shift, AE Lock, White Balance.

* Adjust Primary Focus and framing  parameters: Zoom, initiate /lock autofocus, Manual focus.

* Adjust Secondary Focus parameters: Change position and size of active AF area, manual over ride AF, AF Lock.

Many Capture Phase actions are best carried out with the right thumb and index finger.  Sometimes one of the other fingers is used although the 3rd 4th and 5th fingers of the right hand are more useful as grippers than controllers.  The left hand, either operating as a unit (as for zooming) or as individual fingers (as when pressing a button) also plays it's part.  I will have much more to say about these matters in subsequent posts.  The devil is in the details and many modern cameras impose a suboptimal  experience on the user as a result of an interface design which is not in harmony with human functional anatomy.


Review Now you want to review your photos after capture. This could be via the EVF or monitor. Individuals have their own ideas about review requirements but some typical tasks of this phase would be:

* See the last 1-9 photos made and select one.

* Zoom in to and move around a review image.

* Jump from one image to the next or previous at the same zoom level and position in the frame.

* Delete one/many.

　

　


　

 

When I started to explore ergonomic design in cameras I somewhat naively imagined that a useful way to evaluate a camera would be to hand it to some people, ask them to hold and operate it then seek their feedback. This seemed like a perfectly logical course of action.

In due course I discovered that logical it might be but useful it is not. Why ?

The problem lies in the nature of individual likes, wants and preferences.

These have five characteristics which severely limit their usefulness to a designer.

1. They are idiosyncratic. In other words they are particular to that individual and reflect that person's experience and predispositions, whatever they may be. For instance when Panasonic released the GH3 there was a storm of adverse comment about it from contributors to user forums and some bloggers. It was "too big", "too heavy", it "lacked a soul" (whatever that means) and so forth. Some people were presumably expecting something different and the GH3 may have taken them by surprise. I have one and find it to have the best ergonomics of any camera I have used in 60 years.

2. They are transient. People's likes change with experience. That which a person likes today may be out of favour next month when something potentially more appealing is discovered.

3. They are often unformulated. By this I mean that a person may say they really like or dislike some thing or person or movie or whatever but have difficulty putting the reason into words.

4. They usually do not represent the outcome of a systematic evaluation, rather a snap judgement.

5. They are essentially retrospective in nature. They reflect the present state of a person's experience, which by definition is in the past. Thus they are not very useful as an aid to planning new ideas for the future. They may have something to say about the value of old ideas however. Henry Ford is reputed to have said "If I had asked people what they wanted they would have said faster horses".

So I stopped asking people for their opinions about various cameras' holding, viewing and operating characteristics, because the answers I was getting were entirely unhelpful to the ergonomic design process.

I realised that I would have to proceed by developing an understanding of camera ergonomics based on human functional anatomy and physiology. I would have to develop a language and taxonomy so the subject could be clearly identified, discussed and analysed.