Capture
Phase tasks have the
highest ergonomic priority. They must be carried out while the user is looking
through the viewfinder. Therefore the controls for Capture Phase must be easily
located and operated by feel, using the right index finger and thumb and the
fingers of the left hand. There is no point in allocating user interface
modules (UIM) with icons, numbers or other visual information to Capture Phase
tasks as the module is invisible during capture.
Next down the ergonomic priority list are Prepare Phase tasks. These are
completed in the minutes prior to capture. The camera can be lowered from the
eye so UIMs can be located and adjusted by sight. Modern cameras have lots of modes and Prepare
Phase is the time to change these as required by new photographic circumstances.
We have main capture (exposure) mode, drive mode, focus mode, autofocus mode,
shutter type, stabiliser mode…………and many more.
There are three main types of UIM suitable for Prepare
Phase tasks:
* set-and-see
dials, as my made-up name suggests have inscribed settings or positions which
are visible. Typically the main mode dial, drive mode and focus mode UIMs are
of set-and-see type.
My motion analysis shows that this type is not optimal
for Capture Phase tasks. Despite this,
some camera makers persist in putting
shutter speed dials and exposure compensation dials on the top plate and
aperture rings on lenses. The opportunity cost of this is that set-and-see modules for Prepare Phase
are excluded from those locations.
* Some type of quick access mini menu, Q Menu or
similar, with user selectable items. The UIM which accesses this Q Menu needs
to be reached reasonably easily by either hand but should not be so high on the
camera real estate hierarchy that it displaces a Capture Phase control.
* Programmable buttons with user selectable function,
often called ‘function buttons’. These also need to be reasonably easy to
access but again not placed so as to displace a UIM required for Capture Phase.
These UIMs need
to be designed so they:
1. Are not pressed accidentally while operating the
camera
2. Are easy to locate and operate when desired.
I have lost count of the number of buttons and other
UIMs on cameras owned by me over the years which fail both these criteria.
Camera designers are just not learning.
The priority level of Review Phase tasks depends
to some extent on the user. I often see photographers chimping on the monitor so for some people
quick access to image review is a priority. Presumably aware of this, camera designers often locate a Playback
button right up in a high value real estate position on the camera.
The problem is that a module for Capture Phase action
is displaced down the access hierarchy.
One solution to this is to set Auto Review ON in the menu and allow Playback
button function to be reassigned by the user.
Last in the action hierarchy come Setup tasks which usually involve entering the main menu system and
making selections which should not need to be revisited while out and about
with the camera.
The UIM which initiates access to the menu system can
be in a relatively out of the way place on the camera. However the method for
scrolling around menus and for making selections needs to be easily accessible
and quite streamlined. The 4 Way
controller or equivalent is often used for scrolling around and the button in
the center of the 4Way module is often the one used to enter the menu system or
some part thereof. This is probably
reasonable in cameras lacking a JOG lever (a.k.a. joystick). However a
well designed JOG lever will probably do
the job more efficiently.
User
selected UIM function
The function of most UIMs is determined by the camera’s firmware which
is a type of software. Therefore UIM
function can be assigned in accordance with user preference. Modern cameras
have so many features, functions and modes that it is impossible for any
manufacturer to predict what preferences any individual user will have.
Unfortunately many camera manufacturers persist in
telling users what function should be controlled by each button, dial, lever,
switch etc. In some cases this is probably reasonable, for instance an IS
On/Off switch on the side of a lens. But often this is just a case of the maker
shutting of user options which could easily be provided.
Optimally users will be able to select the function of
each button from an extensive list of options.
Beginners and snapshooters can leave all settings at
default, experts can select camera functions to suit personal preferences.


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