Discovering Camera Ergonomics Part 7 Application of functional anatomy to design

Front view of the Canon Powershot SX60 handle. This is a nice implementation of an inverted L type handle. Note the middle of the shutter button is vertically above the inner side of the handle which is about 34mm wide. This handle is very comfortable and provide s a good grip without strain.  Note the inset handle type strap lug, very functional, no pressure on the hand.  
Canon could have gone further. If the shutter button were to be elevated 2mm more and the profile of the top of the handle lowered about 2mm  then 2 buttons could be placed where I have put little yellow ovals. The front dial is further away from the shutter button than it needs to be, forcing the index finger to make more lateral movement than some users will find comfortable. This camera could easily accommodate a quad control set as depicted in the Mockup #13 photos below. If properly implemented this could dramatically improve operational efficiency.

In their promotional material  some camera makers describe the way they approach the design of a new camera model. This starts with drawings which when approved are used to make a mockup by 3D printing.

If they really do use that approach I think they are going about it the wrong way.

When I make a camera mockup, (to date there are 13 of these)   I start with a basic shape concept (for instance flat top or hump top) and an envelope of width and height with an idea of body depth,  monitor size, EVF eyepiece size, lens size and approximate handle configuration. I then craft the shape in wood, using my hands and fingers to arrive at the detailed shape. Once the shape meets my ergonomic objectives I start adding control modules. These are located where my fingers want to find them.

If the shape which I have created does not allow my fingers to move where they wish, I change the shape until it does. If some part is too large I trim it down. If some part is too small I bulk it up with polyester bog. Sometimes I chuck the whole thing and start over.

This is an interactive process with feedback between fingers, hands and shape at every step of the way.  There is no ‘drawing board’.

Every mockup is a little adventure, every one a bit different, every one a learning experience. 

Mistakes are all part of the process of discovery.

You can see that my mockups have evolved their own characteristic shape. This was reached through a process of  ‘form follows function’ and  ‘function follows fingers’.  They do not correspond to any preconceived ‘style’.

Obviously if this were a process leading to a production camera there would have to be a point at which the engineers ask specific questions like  ‘will the battery fit in there ?’ and so forth. But such questions are part of every design process using any methodology.

Right side of camera, right hand

In this post I will highlight some major issues which illustrate the vital role of applied functional anatomy in the overall design process. Further topics and details of design implementation will be covered in subsequent posts.

Handle shape and tilt

I have spent considerable time and effort over the last five years investigating camera handles. I have used actual cameras and made many mockups of full cameras and handles. I have found that all cameras from about Sony RX100 size and up can benefit from a well designed anatomical handle.

A good handle makes the camera easier to hold securely and also creates opportunities for the efficient location of controls.

I have found that the ‘mini handle’ is optimum for a pocketable camera.

For the next size up, the ‘all day camera’ an inverted L shape is optimal.

Going up a size to the ‘Universal camera’ the ‘Inverted L shape, canted back 10 degrees’ is optimal.

In each case I arrived at the handle which I believe to be optimal by shaping mockups to fit the hand, not by adjusting the hand to fit the camera. Confirmation that I am on, or not on the right path, has been achieved by using actual cameras with many different types of handle and some without a handle.

I experimented with projecting handles, large, small, thick and thin.

I investigated options for parallel handles.

The inverted L shape evolved when I stopped thinking in terms of preconceived ideas and just allowed my hands and fingers to tell the shaping process where it needed to go.

You can read more detail about this in Part 8 of this series.

Here is a quad control set on Mockup #13.  The  index finger is on the shutter button.  during the build, the shape was fashioned first and the buttons located where the fingers wanted to find them.
The front dial is far enough behind the shutter button that neither will be bumped accidentally but both are easy to operate. The index finger can easily drive the camera in Capture Phase using the shutter button, front dial and the two adjacent buttons. 

Top of handle controls, Capture Phase

The inverted L shape handle opens up space on top of the handle for a new approach to UIMs (user interface modules or controls) for Capture Phase adjustments. With careful design and a good understanding of the range of movements which the right index finger can easily make, I place four UIMs on top of the handle. These are the shutter button, front dial and two buttons.

I call this the ‘Quad control set’.

With just these four UIMs and by moving only the right index finger, without moving any other finger of either hand it is possible to efficiently drive the camera in Capture Phase. The shutter button as usual, controls AF and AE then capture, the front dial controls aperture or shutter speed (Mode dependent) and the buttons (press button, turn dial) can be configured to control exposure compensation and ISO (or something else if required). 

The Samsung NX1 has a top-of-handle layout similar to my ‘quad control set’ but unfortunately they fixed the function of the two buttons which was an ergonomic error. The function of those and most other buttons on a camera should be user assignable.

Same mockup and hand as the upper photo, showing how the index finger can easily move to bear on any one of the control modules in the quad control set and do this by feel while looking through the viewfinder.

Thumb support

The thumb has both holding and operating duties in Capture Phase. The arrangements described below allow it to efficiently carry out both simultaneously.

The handle in front needs to be balanced by a thumb support at the rear. Without a thumb support the camera is forever wanting to fall out of the right hand. With a good handle and thumb support the mass of the camera can be comfortably supported with little muscle effort.

I have experimented with several types of thumb support and concluded that the type which allows the thumb to lie diagonally across the back of the camera allows the hand to adopt the ‘half closed relaxed’ posture which provides the strongest hold with least muscle effort.

Mockup #13 thumb support and thumb controls for Capture Phase. This is the neutral position with the hand comfortably in the half closed relaxed posture. The thumb can easily swing right or left without disrupting opposition.

Thumb controls, Capture Phase

The thumb can swing left and right from the basic hold position by movement at the carpo-metacarpal joint. Provided this movement is not excessive, thumb opposition and therefore a firm grip on the camera can be maintained.

Using this understanding of functional anatomy I evolved an arrangement of UIMs with the rear dial embedded in the thumb support to the right of the thumb in basic hold position and a JOG lever to the left, both positioned so the thumb will not have to flex to reach and operate the UIM.

The rear dial is mode dependent. It can be tasked to change aperture or shutter speed or exposure compensation or other function as desired.

Here the thumb has swung right to operate the rear dial. It is a difficult to demonstrate in pictures but the user's hold on the camera remains intact during this operation.  Note the thumb stays straight, it does not have to be flexed which would disrupt grip.

The JOG lever moves left/right, up/down and can be pushed in, towards the body of the camera.  In Capture Phase it is the most direct way to provide fast control of AF area position.  In other Phases of use it can be used for scrolling through menus or moving around a display screen.

On Mockup #13 the JOG lever is located in a very specific position which is where my thumb wants to find it. This requires clipping the top right corner of the monitor assembly. I am assuming this is technically feasible. On my Panasonic GX8 a 4:3 still image preview occupies only 53% of the horizontal dimension of the monitor assembly.

Every camera should have a JOG lever (a.k.a. Joystick) for direct control of AF area position. This one has been positioned exactly where the thumb wants to find and operate it as shown here. I had to chop off the corner of the monitor housing to get the JOG lever in the right place.

With this arrangement the controls directly available to the thumb are required for Capture Phase adjustments which can be made without disrupting grip with the thumb.

Left hand

The left hand has both supporting and controlling duties which must be carried out simultaneously and continuously particularly in Capture Phase.

UIMs on the lens or lens barrel can be used for Capture Phase or Prepare Phase adjustments.

In Capture Phase the UIMs must be easily located and operated by the fingers of the left hand by feel, in landscape or portrait camera orientation and ‘left-hand-under-lens’ or ‘left-hand-over-lens’ holding position.

Prominent circumferential rings with easily located lands or ridges which extend around the whole circumference are best for this.

For Prepare Phase actions other types of UIM on the lens such as buttons, levers, sliders and switches are acceptable. These are usually located on the left side (as viewed by the user) of the lens or lens barrel. This is generally acceptable when the camera can be dropped down from the eye so the UIMs are visible.

The main problem in Capture Phase with these types of UIM on a lens/lens barrel is that they are difficult to locate by feel and often require substantial disruption to the holding/supporting function of the left hand in the process.

Worse, those UIMs are usually located on the left side of the lens barrel in landscape orientation. When the camera is turned to portrait orientation they disappear beneath the lens/barrel, never to be located by feel or sight.