Ergonomic Analysis of Mode Dependent Scroll Wheels

CAMERA ERGONOMICS

AN ERGONOMIC ANALYSIS OF

MODE DEPENDENT SCROLL WHEELS  [MDSW]

Author  AndrewS  May 2012

Introduction  I have spent substantial time over the last two years making camera mockups with the aim of improving the ergonomics of  hand held cameras. One strategy I have used is to explore options for the position and design of User Interface Modules (UIM).  I do this by physically moving buttons and dials to different places on the mockup. This article deals with the Mode Dependent Scroll Wheel.

Definition   There are two main types of control wheels or dials commonly found on cameras.  One is the "Set and See" type. Set and See levers are also popular, often incorporated into a dial type control module. Set and See dials have a single function at each set point although some cameras allow user configuration of the details.

Photo 1 Optimum MDSW Layout

A Mode Dependent Scroll Wheel [MDSW]  has no markings. It's function is dependent on the current operating mode.  It is particularly well suited to Capture Phase tasks.  Thus in Aperture Priority Mode the Scroll Wheel will change Aperture. In Shutter Priority Mode it will change Shutter Speed.

Rationale of the MDSW   Modern electronic cameras suitable for Level 3 users  (Expert/Controller, occasional use) or Level 4 (Expert/Controller, frequent use)  users, are very complex, requiring the operator to make many adjustments very quickly. In the Capture Phase, these adjustments need to occur while the operator is holding the camera firmly with both hands and looking at the subject through the viewfinder. The mode Dependent Scroll Wheel can, if optimally positioned and designed, meet the requirements of that situation.

Photo 2, Good MDSW Location

Job Description for a MDSW  In the Capture Phase, a well designed and located Scroll Wheel should be able, if optimally supported by other User Interface Modules (UIM's) to  adjust Aperture, Shutter Speed, ISO, Program Shift and Exposure Compensation. In addition it provides  scrolling functions in Setup, Prepare and Review Phases. It should not be prone to unintended activation. It should be easily located and operated by feel, while the user is framing the subject with the eye level viewfinder. It must be fully operational without the user having to shift grip on the camera with either hand.

Current Practice  A review of current camera designs shows that some cameras have none, some have one, others two. Some cameras have three. There is no agreement about location. Some cameras have them on the top plate. Some of those rotate on a horizontal axis others on a vertical axis. Some are on the back but there is no common practice as to where precisely they should be located on the back. Some cameras put a Scroll Wheel on the front.

Compare this to the location and operation of shutter release buttons on cameras about which there does appear to be substantial consensus.

Scroll Wheels are in a state of design flux, with no agreement about the optimum number, position or function having yet been reached.

By way of further comparison we can consider the motor car.  Convergent evolution in cars has reached the point where  the main controls are located in the same place and operate the same way in all makes and models.

Photo 3, Poor Front Location

The same kind of convergent evolution has not yet occurred in cameras.

Functional Anatomy of the Human Hand  Camera design is subject to multiple interpretations but the hands which use those cameras do not change at all. They have had the same morphological and functional anatomy for many thousands of years.  I have discussed this in detail in my article "Functional Anatomy of the Hand" on this blog in March 2012.

Briefly, the right index finger is the only digit which has no "gripper" role. It only has "controller" functions. It is the only digit which can operate UIM's  (provided they are correctly designed and positioned)  without affecting the user's grip on the camera.

The Problem with Likes and Preferences  It might be thought that a useful way to discover the optimum arrangement of Scroll Wheels would be to ask camera owners about their likes and preferences. But there are serious problems with this approach. Likes and preferences are idiosyncratic, transient and sometimes unformulated.   They can only arise out of prior experience and as such may give no useful guide to the way forward. The conclusions reached from that experience may be misconstrued.

Photo 4, Difficult Rear Location

Here is an example from personal experience.  I bought and used a Pansonic G1 with a Scroll Wheel located upper front on the handle.  This was unsatisfactory as the right middle finger lay right across the Control Wheel in normal holding position. So, in order to operate the wheel I had to release the camera with  my right hand to allow access to the wheel with my index finger. Thus I could not hold and operate the camera at the same time. Subsequently I bought a Panasonic GH2. This camera has the Scroll Wheel located on the back, upper right where it is operated by the thumb. The GH2 wheel is easier to reach and operate. I might have concluded  incorrectly from this experience that rear/thumb operated Scroll Wheels are "better" than front/index finger operated ones.  However a full ergonomic task, time and motion analysis revealed that although one is easier to use than the other, neither solution is optimal. The way forward lies in a direction different from either of these arrangements.

Another example: I sometimes read on user forums the idea that a camera operator would "like" or "prefer"  to have his or her right index finger resting on the shutter release button "ready-to-make-the-exposure" while the right thumb makes adjustments using various UIM's.  A task, time and motion study shows that typical adjustments in the Capture Phase (AF Area position, Exposure Compensation ISO, Aperture, etc) are made sequentially prior to shutter release. The actions do not occur simultaneously. If these tasks are allocated to the thumb then a better ergonomic description of the index finger's role in the process would be "Sitting-idly-doing-nothing-when-it-could-have-been-adjusting-exposure-parameters".

Photo 5, Poor Rear Location

My point is that user's likes and preferences do not reliably lead us to optimal ergonomic solutions to problems at the Human Machine Interface (HMI).

Analysis of Scroll wheel  locations

1. Rear of camera, thumb operated.  Many cameras have these and they get the job done  in most cases. However if the Scroll Wheel is located directly under the ball of the thumb in basic hold position it will be constantly at risk of accidental activation. If  it  is located to the left , right or below the ball of the thumb in rest position then the user must shift grip with the right hand in order to operate the Wheel. The amount of shift may not be great but it still adds two steps to the process which is suboptimal.

2. Front of camera, below the level of the Shutter Release Button.  The worst of these require the right hand to shift downwards in order to allow the right index finger access to the Wheel. Better ones allow the grip to remain but require the index finger to move a substantial distance to reach the Wheel. 

Best Practice Derived from Ergonomic Study and Mockups  An analysis of task, time and motion shows that the best place for a Scroll Wheel is close to, on the same level as and just in front of or behind the shutter release button.  If optimally designed this location meets all the requirements of the job description.

My experiments indicate the  optimum distance between the center of the shutter button and the center of the Scroll Wheel is 13 mm.  The best ergonomic result is given by a cluster of four UIM's all operated by the right index finger. These are Shutter Release Button, Mode Dependent Scroll Wheel, ISO button and Exposure Compensation button. Both these buttons should permit user selectable function from a substantial list of options.

The optimum distance betweeen the center of the Shutter Release Button or Scroll Wheel and the Exposure Compensation or ISO buttons, is 17 mm.  Each of those UIM's has to have a precisely calibrated physical profile to ensure swift  operation without unintended activation.

Photo 6 Canon DSLR Style

How Many Scroll Wheels ?  My work indicates that IFthe UIM cluster described above is in place and IF there  is a JOG lever correctly positioned for thumb activation then only one Scroll Wheel is required.   The Scroll Wheel changes both Aperture and Shutter Speed in Manual Exposure mode.  In Manual Mode the function of the Exposure Compensation Button automatically switches to  toggle Scroll Wheel action between Aperture and Shutter Speed.  If the UIM's are all correctly positioned in three dimensions the process of adjusting Aperture and Shutter Speed  is quick and becomes almost instinctive.

Photographs

Photo 1, Optimum MDSW Layout.  This photo shows one of my mockups. The Shutter Release Button and Scroll Wheel are optimally angled and positioned on top of the parallel type handle. ISO and Exposure Compensation buttons (both with user selectable function) are optimally located.  It is very easy to locate and operate these four UIM's by feel without shifting grip with either hand. All primary and secondary exposure parameters can be quickly adjusted by the right index finger using this UIM layout.

Photo 2, Good MDSW Location.  This a Samsung NX11, showing good Shutter Release Button position, with the Scroll Wheel 13 mm behind and on the same level, where it is easy to find and operate by feel.  Unfortunately some of the other buttons are not so well located.

Photo 3, Poor Front Location.  The Scroll Wheel on this Canon  G12 is obstructed by the third finger of the right hand in normal hold position. Therefore the right hand grip on the camera has to be released in order to get the index finger onto the Scroll Wheel.  Good idea, poor implementation.

Photo 4, Difficult Rear Location.  The Scroll Wheel on this Panasonic G3 extends from it's housing only about 1 mm. Therefore it must be operated by the very tip of the thumb, just below the nail. You can see the cramped, awkward  hand position which results from this constraint. You can also see the right hand has barely any grip on the camera while operating the Scroll Wheel.  

Photo 5, Poor Rear Location.  The scroll wheel of this Fuji X10 is located right where the thumb wants to be in basic grip position.  In this photo the thumb is pressing on the small thumbrest right at the edge of the camera body. This position is cramped and awkward as you can see in the photo.  There is a brisk trade in after market thumb rests for this and other cameras with the same problem from the same maker.

Photo 6, Canon DSLR Style.  This is a Canon EOS 60D which has a comfortable, well designed grip and mostly well designed UIM layout. However it could easily have been much better. The Scroll Wheel is not on the same level as the Shutter Release Button and is a little further away than optimal. The ISO button is one of four identically sized buttons behind the Scroll Wheel, identified only by a tiny nipple on top, so it is difficult to find by feel.   There is plenty of room on this camera for a more ergonomically productive arrangement of UIM's near the Shutter Release Button. I would describe this camera as a missed opportunity to achieve excellence.

The Lens Lottery

THE  LENS  LOTTERY

Author  AndrewS  May 2012

Introduction  I have enjoyed making photographs and working, or just messing around with cameras for almost 60 years. Along the way I have bought and used many cameras and lenses. In the early days  I assumed, perhaps incorrectly, that one copy of a particular model lens would be the same as the next copy for all practical purposes. However in recent times I have developed the habit of systematically testing every new lens which comes into my hands.   This practice has revealed great variation between copies of many lenses together with a high rate of defects and problems.

Here follows a list of the lenses I have purchased new over the last few years with some comments about each and the cameras which drive them.  Yes, I am a confessed cameraholic, but eBay helps to offset  the cost of my addiction.  So here they are, in vaguely alphabetical order:

Canon EF 70-200 mm f4 L IS   This is the nearest thing to a perfect lens I have ever owned. It is optically and mechanically superb, OIS works really well and it's not outrageously expensive for such a fine optic.  This one gets a STAR  rating from me.  Unfortunately the Canon 60D camera which I chose to drive this lens is not up to the same lofty standard. I thought I would use this combination a lot, but don't for two reasons. First, my Panasonic GH2 with Olympus 40-150 mm lens delivers 95% of the image quality at a fraction the size and weight. Second, the 60D  is plagued  by capriciously inaccurate autofocus to the extent I cannot rely on my photos being in precise focus. Perhaps a more expensive EOS camera body would fix the AF problem, but I am not encouraged by ongoing reports of AF inaccuracy from the EOS 7D and have no interest in going up to full frame. Even if I did the 5D2 has an underwhelming record on AF performance, with many complaints in user forums. By comparison the GH2 nails correct focus with near perfect consistency in single shot operation.

Canon EFS 15-85 mm IS  [First copy] This was returned to the vendor, faulty with obvious decentering, producing marked softness on the left side.  The  [Second copy] was good.  When focussed correctly this lens delivers excellent resolution at all focal lengths.  Unfortunately focus with the 60D is erratic especially at the wide end in SLR mode with the mirror down. In live view mode the camera uses contrast detect AF which is extremely slow, more accurate but still prone to errors.

Canon EFS 17-55 mm f 2.8 IS   This is a good lens with which I made many documentary photos. It would not focus reliably at the wide end on EOS 20D or 40D. The workaround for this was to zoom out to the long end, set AF then zoom back to the wide end. Tedious.

Canon EFS 18-55mm IS kit lens [First copy]  This was the Mark1 version which was surprisingly good optically. I got a good copy in the kit lens quality lottery. AF accuracy was unreliable on Canon EOS 450D.  The [Second copy] was the mark 2 version which is supposed to be better, but I got the wrong lottery ticket and ended up with a bad copy, soft on one side at the wide end and soft on the other side at the long end.

Canon EFS 55-250 mm IS budget zoom  [First copy]  This was the Mark 1 version which was surprisingly good and a real bargain. I should have kept it because the  [Second copy]  the Mark 2 version was not as good, with decentering and  marked softness with loss of contrast at the long end.

Olympus 40-150 mm  This compact Micro 4/3 lens is a  STAR. It delivers most of the performance of  more expensive lenses.  It lacks IS but that has not been a problem for me on the Panasonic GH2.  It should be perfect on the Olympus EM5.

Olympus 75-300 mm  This is another M43 lens from Olympus with very compact dimensions for it's focal length range. No problems but the optical quality is not quite up to that of the Panasonic 100-300 mm.

Pansonic 14-45 mm OIS  I have used two copies of this M43 standard zoom and both have been STARS  with very good to excellent image quality across the focal length and aperture range and no mechanical or optical defects.

Panasonic 14-42 mm OIS kit zoom  My copy of this was faulty.  Optically it was reasonable but it was unpredictably prone to double imaging for reasons I never determined, maybe a case of Shutter Shock Syndrome  (See my post about S.S.S. on this blog) involving the OIS module.

Panasonic 45-200 mm OIS I have used two copies of this both showing the same characteristics.  From 45 to about 120 mm focal length the lens delivers very decent results. But at the long end it exhibits loss of contrast and sharpness with a tendency to misfocus even on the GH2 which has an exemplary focussing performance with most M43 lenses.

Panasonic 45-175 mm PZ OIS  Presumably this was intended to be Panasonic's upgrade  to the somewhat outdated 45-200 mm. I bought one in November 2011 and found it to be totally unserviceable. It was faulty with severe jitter effect (double imaging) in all operating conditions. It went back to the vendor for a refund.  Some, but not all, users have reported the same problem. I have not yet seen any acknowlegement from Panasonic that a problem even exists.

Panasonic 100-300 mm OIS  This is another super zoom lens for M43, with overall very decent performance. My copy shows a bit of decentering evidenced by softness on the left side at most focal lengths. Ortherwise it is a good lens suitable for hand held use on Panasonic OIS bodies.

Samsung NX 18-55 mm IS  My [First copy] of this was a bit soft at the long end but otherwise turned in a very decent performance for a budget kit zoom. The [Second copy] was even better with good sharpness at all focal lengths.

Samsung NX 30 mm f2  This is a STAR lens in Samsung's lineup, with an excellent rating in all aspects of performance.  A very small lens with a big performance.

Samsung NX 20 mm f2.8  My [First copy] of this was a poor performer with low resolution and poor resistance to flare. It was retured to the vendor. The [Second copy] was better, delivering good sharpness stopped down a little. But the flare problem remained.

Samsung NX 50-200 mm OIS  My [First copy] of this is slightly decentered evidenced by a little softness on the right side at 200 mm. This one also has a slightly sticky zoom action. I tried two further copies to see if I could find a better one. The [Second copy] was faulty with poor sharpness at the long end so it went back to the vendor. The [Third copy] had a nice smooth zoom action but was not quite as sharp as Copy 1 at the long end. So I kept the first one.

Summary  Of the 25 lenses listed here, one was completely unserviceable on delivery. This and 3 others were returned to the vendor as fauly. Seven others had faults or defects impacting on image quality. Fourteen had no faults or defects. That is a rate of  56% with no obvious faults and 44% with a fault or problem affecting operation and/or image quality.

Conclusion   As you can see from this experience, the bad copy rate in new lenses is disappointingly high. There does appear to be a tendency to less problems in the higher price range but even expensive lenses are not immune from trouble. I see no trend to prefer one manufacturer over another.   It would appear from my reading of reviews and reports that all brands have a percentage of  bad copies.   The further disappointment about this issue is that lens makers rarely acknowlege problems publicly and rarely issue recalls.

Recommendation to buyers     My suggestion is to buy from a vendor which guarantees replacement or money back on return. The rate of bad, or at least "not best" copies is so high that any buyer who acquires more than 2-3 lenses is almost guaranteed to encounter a problem. You may find it worth buying from a real shop with a real live sales person who you know by name, and more importantly who knows you and respects your judgement.

I suspect that most retail customers who report a "problem" with a camera or lens are probably not using their equipment correctly. So, when you present yourself to the vendor claiming to have faulty equipment make sure you have in hand  good evidence in the form of hard copy photographs illustrating the problem.

Panasonic 100-300 vs Olympus 75-300 Lens Test

MICRO FOUR THIRDS SYSTEM EQUIPMENT

LONG TELEPHOTO ZOOM LENS COMPARISON

Panasonic 100-300mm OIS  VS  Olympus 75-300 mm

Author  AndrewS  May 2012

Introduction           With the release of new lenses and camera bodies, there has been a recent surge of interest in the Micro 4/3 system.

There are two long telephoto lenses designed specifically for the M43 system, the Panasonic 100-300 mm OIS and the Olympus 75-300 mm without IS.  These both offer the real prospect of handheld ultra telephoto photography in a compact, lightweight, moderately priced  package.

Photo 1

I bought and have tested both on a Panasonic GH2 body.  I will re run some of the tests with and without IBIS on the Olympus EM5 when I can obtain one.

Notes for potential buyers     1)  Results reported here are valid for the specific copies which landed in my posession. In my experience of the lens lottery there is considerable sample variation between copies of the same lens. This can be greater than the difference between one model and another.  2)  These are both super telephoto lenses, best suited to use on a camera with EVF.  They are not, in my view, suitable for hand held photography using monitor view only, as they need to be held very steady, using good technique.  3)  while testing these lenses, I encountered the highly unwelcome phenomenon which I have called "Shutter Shock Syndrome"  [S.S.S]  which you can read about elsewhere on this blog.

Photo 2 Crop from Photo 1

S.S.S.  is a real and significant problem with the Panasonic GH2. I have not tested any other M43 body.

Tests  With both lenses, I photographed distant subjects (100 meters - several kilometers) and test charts at closer distances (8-20 meters). I ran series of exposures on a sturdy tripod, on a monopod and hand held. I used subjects of different types, some with fine detail, some with high contrast, some low contrast, some backlit. This produced several hundred frames from each lens.

Description and specifications  You can read all the details elsewhere, but my impression after using both for several weeks is that the Olympus lens feels significantly more compact in operation and in the camera bag than the Panasonic. This could be the most important issue for some users. The Olympus also zooms more smoothly whereas the Panasonic tends to get a bit jerky when zooming slowly. The Panasonic comes with a soft pouch and lens hood, the Olympus has neither. Based on B&H New York prices the Panasonic is considerably less expensive.

Photo 3 Olympus 75-300 mm lens 200% crop

Focussing Both achieve AF and MF with about equal speed and accuracy on the GH2.

Image Quality  I had to run many tests in different conditions to separate the two, which should tell you they give similar results in most situations. Testing was complicated by the Shutter Shock Syndrome  referred to above and also by the finding that the two lenses perform a little differently when comparing closeup with distant subjects.  In addition my copy of the Panasonic is slightly decentered, producing  some softness on the left edge of the frame at most focal lengths.  This softness cleaned up somewhat by stopping down the Panasonic one stop. Apart from that both lenses appeared to perform just as well wide open as stopped down at each focal length.  On several test runs I found the Olympus at 300 mm gave better results at f6.7 than any smaller aperture.

With distant subjects the Panasonic produced slightly but consistently better resolution of fine details and better clarity across the frame than the Olympus at all focal lengths and apertures. With subjects, including the test chart,  8-20 meters from the camera the difference between the two was less clear cut although I scored a slight advantage to the Panasonic after much pixel peeping.  Neither lens rendered the test chart with as much clarity and resolution as lenses of shorter focal length such as the Panasonic 14-45 mm OIS or the Olympus 40-150 mm.

Photo 4 Panasonic 100-300 mm lens 200% crop

Both lenses delivered good contrast. The GH2 corrects for chromatic aberration with the Panasonic lens but not the Olympus lens which showed significant CA towards frame edges which would require correction in post capture processing.

Conclusion  Either of these lenses is capable of good to very good results if used with care, handheld, on a monopod or on a tripod.

I would not recommend pairing the Olympus lens (no OIS) with a Panasonic body (none has IBIS at this time).  Some form of IS is required for accurate hand held framing and composition at the long end of these superzoom lenses.

The Pansonic lens works just fine on the GH2, with the OIS providing good stabilisation of the viewfinder image. I will discuss the effectiveness of OIS in this and other Panasonic lenses in another post on this blog.  It should also be suitable for the Olympus EM5 but I have not been able to test this yet.

Overall the Panasonic costs less and delivers better resolution which I suspect will make it the clear choice for most buyers.

Photographs

Photo 1  This was made on a windy day, with air turbulence causing atmospheric distortion of the subject which was about 1.5 kilometers from the camera. I rested the camera on a folded towel on the roof of a motor car. This gave much better stability than a tripod in the windy conditions. Panasonic GH2, Panasonic 100-300 mm lens at 197 mm, f 6.3, 1/1600 sec ISO 160.

Photo 2 is a crop of Photo 1 showing detail.

Photos 3 and 4  are 200% crops of a static subject about 400 meters from the tripod mounted camera. Focal length 124/127 mm, 1/640 sec @ f 5.6, ISO 160. Photo 3 is the Olympus, Photo 4 the Panasonic. This illustrates the slightly better resolution delivered by the Panasonic lens.  

 

 

How Effective is Panasonic OIS ?

MICRO  FOUR THIRDS CAMERA PRACTICE

HOW EFFECTIVE  IS PANASONIC OIS ?

Author AndrewS  May 2012

Introduction    I recently conducted a systematic evaluation of Panasonic OIS using a Panasonic GH2 body with Panasonic 14-45 mm, 45-200 mm and 100-300 mm OIS lenses. In standing posture the camera was handheld for all exposures, using the EVF.  I held the camera as steady  as possible for each exposure using the same holding, breathing and shutter release technique for all shots. I photographed the center section of a test chart at shutter speeds from 1/4 sec to 1/1600 sec with OIS off for the first run then on for the second run. I repeated the whole test twice to check for variable results, which I found.

Limitations of method     Before detailing the findings I should say that measuring OIS effectiveness is an inexact process. There is considerable variation in camera shake from one frame to the next and deciding what is sharp and what is not sharp is to some extent subjective. So my second run of tests gave a slightly different result from the first.

Panasonic 14-45 mm OIS lens  Tested at 45 mm.  I was able to get sharp results handheld down to 1/80 sec with OIS off and 1/30 sec with OIS on. The improvement was 1.3 shutter speed steps.

Panasonic 45-200 mm OIS lens  Tested at 200 mm.  I got sharp results down to 1/320 sec with OIS off and 1/250 sec with OIS on, an advantage of 0.3 steps.  If I would accept slightly soft frames, that grew to 2.6 steps. You can see how the subjective factor comes into the equation.  There was a group of frames in the 1/100 sec to 1/200 sec which my notes record as "very slightly blurred".

Panasonic 100-300 mm OIS lens  Tested at 300 mm.  Results with this lens were variable. On my first run there was a benefit of 1.3 steps. On the second run I got sharp frames down to 1/500 sec with OIS off and 1/320 sec with OIS on, for a benefit of 0.3 steps. However if I would accept a slight amount of softness this increased to 1.0 steps. 

On both runs with this lens the OIS produced a markedly bimodal effect. There was a group of quite decently sharp frames from 1/25 sec to 1/50 sec, then a blurred group from 1/60 sec to 1/160 sec with sharpness improving again from 1/200 sec.

Findings 

1. None of the test runs showed a worse result at any shutter speed, hand held, with OIS on compared to OIS off.  The implication is that with these three lenses on this camera body there will be no harm done by leaving OIS on for all handheld shots.

2. The most useful thing about  OIS is it's ability to stabilise the viewfinder image when using telephoto lenses especially at the long end.  The 100-300 mm lens at 300mm with OIS on is eminently usable hand held in good light, which is remarkable considering the angle of view is only 4.1 degrees.

3. OIS does extend the useful hand holding shutter speed range of each lens by a small amount.

4. The most important factors in achieving sharp photos hand held are, in order of importance as indicated by the results of my trials:

a)  Good camera hold and shutter release technique. This includes posture, breathing, holding and finger movement control.

b)  Sufficiently fast shutter speed.  The old rule which says go no slower than  the reciprocal of the focal length (x2 for M43) is still useful.

c)  OIS can provide a small but potentially useful downwards extension of the useful hand held shutter speed range, but it is not a panacea for poor handholding technique.

5. I am at a loss to explain the bimodal effect of OIS with the 100-300 mm lens.

Panasonic GH2 Camera Ergonomic Review

MICRO FOUR THIRDS PHOTOGRAPHY

Ergonomic evaluation of the Panasonic GH2

Author  AndrewS   May  2012

This is a user report after several thousand exposures in general photography settings, mostly hand held, mostly outdoors, with a selection of Panasonic and Olympus M43 lenses.

The mission of this blog is to increase consumer awareness of ergonomic issues in camera design, so most of the report is about ergonomics, however I will touch briefly on features, image quality and performance of the GH2.

Description and Features (highlights)  This is Panasonic's top M43 body clearly aimed at Level 3 (Expert/Controller, occasional use) and Level 4 (Expert/Controller, frequent use)  users. It also has a high level of video capability, not reviewed here, as there are many differences between the still and video user experience. The video button is located in a high priority zone just behind the shutter button and disappointingly, cannot be user tasked to any other function. So if I am not shooting video the button is blocking prime camera real estate which I would like to use for a primary exposure parameter such as ISO.

Photo 1 GH2 Top Plate

Some features of the GH2 are worthy of note.  The multi aspect ratio sensor has proven more useful and gets more use than I expected. I have allocated AR selection to the fn1 button on the top plate and raised the height of this button by 1.5 mm by adding a little disc of stainless steel fastened by super glue. Now I can locate and operate this button by feel (which I could not do previously) while looking through the EVF. 
The AF/AE Lock button can be set to start/lock AF. This separates AF from exposure which is often desirable especially when using the focus and recompose technique.
The top plate has two Set and See dials and two Set and See levers allocated to Prepare Phase camera operation. This represents the best use of Set and See UIM's and works very well in practice. I can see  directly and quickly change what shooting mode and drive mode are set and see directly what focus mode and exposure area are set.  Photo 1  shows the set and see UIM's.

Some of the UIM's allow user set functions. This is highly desirable as no camera maker can predict all the permutations of UIM function which an individual photographer might prefer. Panasonic and all other makers would do their customers a big favour by extending user configurability to most UIM's, providing a choice of almost all functions of which the camera is capable. 

Photo 2 Blown highlights

Image Quality  I rate IQ as acceptable for the target user group. Matters most needing improvement are (1) Noise, which is present even at ISO 160 in shadows, particularly in the blue channel (2) Dynamic Range which is just acceptable with many subjects but if greater would lead to less (3) Highlight clipping which is a frequent occurrence especially outdoors in Australia where scenes with  high subject brightness range abound.  Otherwise I have some reservations about this camera's color reproduction with several images not quite rendering the subject as I saw it at the time.  Photo 2  illustrates blown highlights on the wheat silo structures.

Performance  With one shot still photography performance is very good.  AF is sensitive, fast and very consistently accurate, much better than any of the many SLR and DSLR cameras I have used over the years. Manual focus is well implemented, easy to perform with automatically magnified view and very accurate although the absence of distance scales on the lenses is lamented. It is not possible to preset a specified focus distance.   Shot to shot times  are quick, with good overall responsiveness.

Continuous shooting/AF mode is much less satisfactory. The AF system can keep slowly moving subjects in focus, but  EVF blackout after each frame is significant. As a result tracking a moving subject is difficult.
Exposures are generally excellent. The camera regularly makes auto exposure judgements which make best use of the available dynamic range.

Ergonomics   The three elements of ergonomics are Holding, Viewing and Operating.

Photo 3 Relaxed Natural Hand Position

Holding   The GH2 has the shape of a DSLR with a hump on top and a projecting handle, but reduced in size.  This camera's existence and identity depend on it being different from a  DSLR so why the product development people at Panasonic gave it a DSLR shape is an abiding mystery to me. Whatever the reason, that decision has a big effect on holding and operating characteristics. The projecting handle design works on larger cameras because the right hand is opened up when gripping the handle. But on the GH2 (and G1,G2,GH1) the projecting handle is much smaller so for adults with average sized hands the handle shape and UIM locations are at odds with the natural half closed holding position of the hand.  The photos tell the story more clearly than words.   One benefit of  the projecting handle design is that it makes the camera easy to carry in the right hand, ready to go.

Photo 4 GH2 Attempted Natural Grip

Photo 3   Shows the natural, relaxed half closed hand position. Best design practice would shape the camera to fit the hand in this position.

Photo 4  Shows an average sized adult male hand holding the GH2 in the nearest possible approximation to a natural grip. You can see the index finger is looking for a shutter release button somewhere in space and the thumb is nowhere near any of the UIM's.

Photo 5  Shows what the same hand is forced to do in order to place the index finger on the shutter release button and the thumb on the AEL/AFL/AF Start button. The whole palm of the hand has to lift away from the camera leaving only the middle finger actually holding the handle.

Photo 5 GH2 Forced Grip

Photo 6  This shows one of the mockups I have built. This one is the same height as the GH2, a little less deep and 20 mm wider.   It fits easily into the same compartment in my camera bag as the GH2. It is much more comfortable and secure to hold than the GH2. All primary and secondary exposure and focussing parameters can be adjusted in the Capture Phase of use without shifting grip at all.

Photo 6 Mockup Designed For Natural Grip

Viewing   Viewing arrangements on the GH2 are generally very effective.  The monitor is of the swing out type, which is handy in many situations and protects the screen when closed. The EVF is large, bright and clear, with excellent data under and overlays and plenty of user configuration.  There are newer and arguably better EVF's now available but that on the GH2 is still very usable in single shot mode.

Operating   For the photographer who makes occasional pictures the GH2 will very likely be quite satisfactory. But for the user who wants to make several hundred photos per day, the GH2's operating systems may become frustrating.

The shutter button is perched top and front on the projecting handle which is not where the index finger wants to find it.

The Main Control Dial (MCD) is incorporated into the thumb rest and is operated by the right thumb. On the G1 and GH1 it was top and front on the handle where it was completely obstructed by the middle finger of the right hand. So they moved it to the back where at least you can now reach and operate it. However this involves derotating the thumb metacarpal and flexing the thumb interphalangeal joint, so as to bring the tip of the thumb to bear on the dial. All this means the user cannot effectively hold the camera with the right hand and operate it at the same time. This means one has to support the weight of the camera and lens with the left hand while operating it with the right hand.  While not disastrous this does provide a suboptimal user experience which could easily be improved with better ergonomic design. The MCD has a "Push-Push"operation.  Push to change it's function from controlling Aperture or Shutter speed (depending on shooting mode) to Exposure Compensation. Push again to return to the former function.  This is clever and it works.  However my own experience is an exposure error rate of about 5%, rising to 10% when I am working fast, caused by inadvertently activating Exposure Compensation by pressing slightly too hard on the dial while turning it. This problem can be removed with the Custom Menu, Page 5, Top line, Expo Settings > Switch by pressing the LVF/LCD button.

The rear control panel is very small. In consequence all the buttons are tiny and all but the AF/AEL button are either recessed or smoothly rounded.  Despite several month's diligent practice I  cannot reliably locate the buttons on the 4 way controller by feel while looking through the EVF.  This in turn means I often have to look at the buttons to find and operate them. In the case of the ISO and fn2  (to which I have allocated AF area selection) these initiate Capture Phase tasks which should be easy to complete while looking through the EVF but are often not.  The other problem in this part of the camera is that I often bump the WB button by mistake due to it's location very close to the edge of the camera.  I tried to raise the tactile profile of the 4 way controller buttons by placing a drop of clear epoxy on each. This has been partly successful but the basic problem persists.

The ON/OFF switch is acceptably accessible. Having used cameras with O/I switches almost everywhere I find those around the shutter release button can be operated by touch, without having to look at the camera to determine whether it is on or off and to switch from one state to the other.   The Q Menu is a good idea which could have been much better implemented  by allowing the user to choose the items allocated to that button.

Summary  As a stand alone item the Panasonic GH2 is a good, but not outstanding,  product with acceptable features, image quality, performance and ergonomics for a Level 3 user.

The main appeal of the GH2 is that it provides an entry point into the M43 system with a substantial and growing selection of lenses, a thriving on line community and prospects for future development.

The Way Forward   Operation of the  GH2 in it's existing form could be somewhat improved with the following minor changes:  1) Make function of the video button  and all 4 way controller buttons user assignable from a long list of options, 2) Make contents of the Q Menu screen user assignable, 3) Slightly modify the thumbrest and main control dial for easier access and operation, 4) Replace the 4 way controller buttons with a "rocking saucer" type controller which is much easier to locate and operate with the right thumb by feel.  

However if Panasonic wants to become a "First Choice" option for  Level 4 users, then I believe major changes are required.  It is possible to design a camera about the same box size (w x h x d) as the GH2 but with greatly improved ergonomics.  I know this because I have been researching, designing and building camera mockups for the last two years. Details can be found in previous posts on this blog site.  

This work has led me inexorably to the realisation that for any given box size (w x h x d) the best ergonomic result is given by the flat top, "Rangefinder Style" design as shown in the photograph. This puts the viewfinder in the optimum position for the 90% of people who use the right eye and is no worse than the "hump" location for left eye users.  It allows a higher, fully contoured anatomical parallel type handle providing full five finger grip. It allows the shutter button to be located where the index finger wants to find it and the main control dial to be located just in front of or behind the shutter button.  All the other controls can be much larger and easier to operate by feel.   There is no functional or ergonomic downside to the "Rangefinder Style" body design for a mirrorless interchangeable lens camera.

Micro Four Thirds Shutter Shake Syndrome S.S.S.

MICRO 4/3 CAMERA PRACTICE

SHUTTER  SHAKE SYNDROME  [S.S.S.]

Author AndrewS  May 2012

This week I have been running tests to compare the Panasonic 100-300 mm lens with the Olympus 75-300 mm, both on my Panasonic GH2 camera in a variety of situations and shooting conditions.  Somewhere in the middle of several hundred test photos I discovered some which exhibited marked blurring with  double image effect.  So I had to embark on a tangential line of enquiry to figure out the cause of these highly unwelcome fuzzy frames.

Blurred  frame with double imaging

I ran tests on the Panasonic 45-200 mm and Olympus 40-150 mm lenses as well as the two longer zooms. My findings are:

1. S.S.S. Occured with the camera on a sturdy tripod, well grounded, shutter activated by wired remote or timer delay. Outdoor shots were made on a calm clear day with no wind. Indoor shots used a test chart and the same tripod. The tripod head was attached by the socket on the camera body.

2. The phenomenon occured with OIS (only relevant to the Panasonic lenses) switched ON or OFF.   It also occurred with Olympus lenses (no OIS) on the Pansonic body (no IBIS)  so it cannot be attributable to any form of IS. All four M43 lenses are good copies, working properly.

3. Image blurring appeared with all four M43 lenses in the shutter speed range 1/20 second to 1/200 second, with the worst examples around 1/100 second. Mysteriously, most but not all frames at the critical shutter speeds were affected. Most severely affected were the longer lenses at their longest focal length.

4. I tried holding on to the camera while it was on the tripod in an attempt to dampen vibrations. This did not improve matters at the higher end of the S.S.S. range (1/100-1/200 sec) and made things worse at the lower end of the range ( 1/20 - 1/60 sec).

5. I ran a series of test shots with the GH2 plus 100-300 mm lens @ 300 mm, on a monopod, OIS  ON. Obviously slow shutter speeds gave blurry results. But at the upper end of the critical range for S.S.S, the pix were blurred up to about 1/200 sec, worst at 1/100 sec, coming good at 1/250 sec and faster. 

These findings indicate that I cannot get reliably sharp shots between 1/30 sec and 1/200 sec with the Panasonic 100-300 mm or Olympus 75-300 mm lenses on the Panasonic GH2 body, by any means at all.

This is relevant for the work which I want to do with these lenses which is telephoto landscape and cityscape.

6. I ran the tripod mounted  tests with a Samsung NX11 and NX 50-200 mm lens. This combination also showed some S.S.S.  in the 1/60 - 1/200 sec shutter speed range. My notes describe the images in this range as "a bit soft".  In other words the S.S.S. effect was present but not as noticeable as the GH2.

7. Next up was the Canon 60D with EF 70-200 mm f4 L IS lens.  On the tripod without mirror lock up (MLU) images were extremely blurred at 1/4 and 1/8 sec due to mirror slap, but good at slower and faster speeds.  In live view mode  with the mirror up I saw no convincing evidence of S.S.S.  One frame at 1/200 sec was soft but this could have been due to unreliable focussing which plagues this camera. This camera uses electronic exposure start in live view mode. The mechanical shutter is used only to end the exposure. I would therefore expect no problems with S.S.S and found none.

My hypothesis is that the the quadruple action shutter used on the GH2  (and other mirrorless cameras) is the cause of the problem. This has a close>open>close>openaction on each exposure. The initial close>opensequence produces vibrations which occur during the exposure and can easily be felt with a hand placed gently on the lens.  If  I am correct, an electronic first curtain shutter should eliminate the problem.

I wondered initially why OIS was unable to prevent the blurring then on reflection realised that OIS is designed to compensate for instability caused by manual handling which produces relatively large, slow movement cycles. But the shutter produces a short, sharp shock (another S.S.S. !) which passes through the body/lens mass before for OIS can respond.

So, while waiting for the next GH camera iteration, hopefully with a different shutter system, I will try to remember that I must avoid firing solutions (Aperture, ISO, Shutter Speed) which produce speeds in the S.S.S danger range.

Note: Last year I bought a Panasonic G3 and 45-175 mm OIS lens. This combination produced a very severe case of S.S.S. at almost all shutter speeds such that the lens was not serviceable so I returned it to the vendor.  I believe there was probably a fault in the OIS module of that lens making it excessively sensitive to shutter vibration with the OIS switched ON or OFF.  OIS appears to be working normally on the Panasonic 45-200 mm and 100-300 mm lenses tested for this report.

Evaluate Your Own Camera's Ergonomics

CAMERA ERGONOMICS

D.I.Y. ERGONOMIC EVALUATION

How to rate the ergonomics of your own camera

Author AndrewS

Abbreviations    HMI = Human Machine Interface

                            UIM = User Interface Module (buttons, dials, levers)

1. Know thyself     What kind of photographer are you ?  From the perspective of HMI (Human Machine Interface) requirements I would identify four levels of camera user.

Level 1, Snapshooter, occasional use.

Level 2, Snapshooter, frequent use.

Level 3, Expert/controller, occasional use.

Level 4, Expert/Controller, frequent use.

The occasional snapshooter will be well served by a very small compact or phone cam. The key requirements are very compact size and easy, fully automatic operation.   Some shapshooters take lots of photos but don't want to be bothered by shutter speeds, apertures and the like. The key requirements are simple, fully automatic operation, responsiveness, decent image quality and  conveniently compact size.

The expert/controller will want a camera which provides much greater opportunities for user control over the camera's functions, with decent viewing and holding as well.    For the occasional user, suboptimal performance and ergonomics may be acceptable as a  tradeoff  for lower size/cost.

The frequent expert user wants the lot. High image quality, excellent performance, good handling, good viewing qualities and excellent operating characteristics. The frequent user will accept higher cost and size to get improved viewing, handling and operating qualities.

The point of this is that a camera which is acceptable to one user could be intensely frustrating for the next.      A camera suitable for user levels 1 and 2  will be of little  interest to a level 4 user. However a camera with all the controls to satisfy  level 4 operation  user could suit level 2 users very well when set to one of it's fully automatic shooting modes and will be very satisfactory for level 3 users in any shooting mode.   For the remainder of this presentation I will be referring to cameras suitable for the level 4  use.

Photo 5, Natural Hold

2. Describing ergonomics  It is possible to describe, classify and rate the ergonomics of a camera with reference to characteristics which can be observed by anybody who understands what to look for.  This exercise can be carried out completely independent of a person's likes and preferences.  In order to do this the reviewer needs to become aware of the language and principles of ergonomics. For a full discussion of these matters please read Parts 1-12 of my discourse on camera ergonomics in this blog. At the very least please read Part 11 and the summary "Ergonomics in a Nutshell".

There are three main descriptors of a camera's capability: image quality, performance and ergonomics. The first two have a very well developed technology, language and principles by which these capabilities can be  measured and described. But the current state of ergonomic analysis is inadequate, as is the ergonomic capability of many new camera models.  Early reviews of new camera releases have much to say about image quality and performance, but appreciation of ergonomics may require long term use, with little reporting of insights thus gained.

3. Complexity and information overload    My first "serious" camera was a Pentax Spotmatic.  This camera allowed  you to adjust shutter speed, aperture, focussed distance  and nothing else.   You could adjust film speed when loading a new roll of film and that was yer lot. By comparison the modern electronic camera presents it's user with hundreds of adjustable parameters leading to information overload every time  a photograph is made.  This presents a huge ergonomic challenge to the designers of modern cameras. You will not be surprised to find that some makers respond to this more effectively than others.  But you might be surprised and perhaps disappointed  to discover that camera makers who have been in the business a very long time are no more successful than recent arrivals on the camera making scene. This means you cannot rely on a brand name to deliver good ergonomics.

Photo 1 Top

4. First acquaintance  One of the first things you do with a new camera is look at it.  With experience, this can reveal a lot. Is it a DSLR ? With this type of camera you can have eye level view or live view on the monitor but it's either/or, with each view type providing a different user experience and focussing technology. You can't segue seamlessly from one to the other. Sony SLT cameras use a type of SLR technology which does allow the same type of operation in eye level and monitor view. Is the camera a mirrorless type (MILC) designed to look like a mini DSLR with a hump on top ? There is no functional requirement for this shape so I have to assume the makers use it for marketing reasons, perhaps believing buyers will recognise this as the shape of a  "proper" camera.  If they used the flat top "rangefinder style" shape with the same dimensions and EVF located near the top left corner, Leica style, they could achieve a dramatic ergonomic improvement, with more natural viewing using the right or left eye,  lens axis shifted to the left (as viewed by the user), a taller and more anatomically shaped handle, much larger rear control panel and much more user friendly interface modules (buttons, dials, levers etc).  Are there "Set and See" dials and/or levers on the top plate ?  If well designed, these can be extremely handy for adjustments required in the Prepare Phase of use. Are there buttons on the left side of the body ?   These can be useful for Prepare Phase adjustments but are incompatible with smooth operation in the Capture Phase.

Photo 2 Rear

4. Setup Phase     Before taking photos with a new camera it needs to be set up to suit your individual requirements.      There can be a multitude of parameters requiring attention with some cameras having more options than others. Items typically include time and date, language, file and folder settings, display settings, color space, RAW capture, sounds, user interface module (buttons, dials, levers) tasking, aspect ratio, sensor cleaning, monitor and EVF display settings, AF priority, MF assist, focus peaking, analoge distance and depth of field display, EV steps, AEB settings, noise reduction, AF assist lamp, video modes and options, ......etcetera......etcetera.

Does you camera have an instruction manual ?  Is it useful ?  Does your camera have a menu system which is clear, logical, and easily accessible ?  Does the camera have user interface modules which allow easy scrolling and selection of items ?  Is there quick access to a user configurable "My menu" for frequently used items ?  Are menu items grouped in a way which makes sense to the user ? Some cameras have a convoluted menu system in which a change to one item in one folder of the menu system can force unexpected and sometimes inexplicable changes to other items in different folders.

Are most UIM's user configurable from the full list of camera functions ?  Configurability is extremely important in an electronic camera with hundreds of  adjustable parameters and potentially thousands of combinations. Be very wary of cameras with manufacturer set single functions on UIM's.   

Are the UIM's for Setup Phase located in a low priority area of the camera, where they should be ? Or has the maker put the Menu button in a high priority area which would have been better allocated to a Capture Phase control ?  See "Locations" on this blog for more about camera real estate.

5. Prepare Phase  Now you want to start making photos.  The Prepare Phase of use  refers to the minutes just prior to image capture. You need  to adjust camera settings for the current assignment, be it landscape, potrait, sport/action, flash indoors or whatever.

Cameras and users vary of course but typical parameters requiring adjustment at this stage include setting P,A,S or M shooting mode, drive mode, flash mode, OIS, video mode and dynamic range control. Also in this group are tertiary exposure parameters including metering mode and white balance. Then we have tertiary focussing parameters including focus type (phase detect/contrast detect) AF mode (single/continuous/tracking/predictive) AF area/type (selection/multi/face detect) AF/MF. There may also be lens based  focus controls including Stabiliser ON/OFF, stabiliser mode, AF/MF and focus distance limiter.

For optimum ergonomic operation the user should be able to make all adjustments in this phase without having to enter a menu.  "Set and See"  dials/levers are very useful for this stage as settings can be seen at a glance and adjustments made quickly. Other UIM's, such as buttons,  for this phase need to be located in a medium priority zone on the camera. There needs to be a quick, effective means of scrolling around then selecting options in this phase.

Some cameras use a "Quick Menu" for access to Prepare Phase adjustments. This can work decently well provided that the access module (usually a button) is located in a high/medium priority zone, contents of the Q Menu are fully user selectable and scrolling/selecting options is fast and efficient. A well located and designed JOG lever can be faster than the ubiquitous 4 way controller for this purpose.  It is desirable to give users the option to "set" selections either by pressing a specified button or half pressing the shutter button.    Some cameras only offer  manufacturer preset options in the Q Menu. From an ergonomic perspective, this can be extremely irritating as the review screen will usually be cluttered with items you personally do not want, while other items you do want on the Q Menu are not to be found.

6. Capture Phase   Now we come to the sharp end of ergonomics.  A photographer who wants to take control of the process of image capture has a great deal to do in a very short time.  He or she must note and consider numerous data inputs then make a series of decisions leading to immediate actions at the point of sensor exposure. The process requires an operator with knowlege and practice. It also requires a camera designed  by photographers  to ensure it is optimised for ergonomics.  There are three main tasks in this phase, holding, viewing and operating.  At the risk of labouring the obvious, I would point out that all three tasks must be performed simultaneously. Unfortunately,  too many modern cameras make the job far more difficult than it needs to be.

Photo 3 Set and See Dials

Holding  Please refer to Parts 4, Functional Anatomy, 6, Hands and Fingers and 7, Handles and Holds,  for detailed discussion.  Please find the time to read these chapters of the story of ergonomics as they contain much information. A fully sculpted, anatomical handle and thumb rest allow the user to obtain a secure and stable hold on the device. This is the functional platform which forms the base for good operation. Good handle and thumbrest design is not something which can usefully be stuck, like an appendage, onto some pre-existing camera shape. For optimum ergonomic function the handle and thumb-rest need to be an integral part of the total design from the ground up.      Please refer to Parts 10, Operating Systems and 12, Mockups, for more discussion on these issues.

Questions to ask when evaluating your camera's holding include: Does it have a comfortable, anatomically sculpted handle and well shaped and positioned thumb rest ? Does the camera encourage the user to hold it with the natural "half closed' position of the right hand ?   Can you operate the main Capture Phase controls without disrupting grip with either hand ?

Viewing  Please refer to Part  9, Viewing systems for detailed discussion.  The total spectrum of viewing systems on modern cameras is very complex. As a user you need to view two completely different cognitive categories of information. The first is preview/review of the image captured. The second is camera status data. 

Questions to ask include: Does my camera have a monitor screen and eye level viewfinder ? Each has it's uses, not always interchangeably.  Is there a seamless segue from one to the other ?  Can the monitor be tilted/swung/swivelled ? Is camera status information displayed beneath (easier to see) or superimposed on (harder to see) the image preview/review ?  What is the quality of the preview image ?  Can the display be user configured ?  What range of options is available ?  Is the effect of adjustments made with UIM's immediately evident on the monitor and eye level viewfinder ? Does this include both the image preview appearance and data readouts ?  Is the image preview accurate as to boundary and appearance?  Are there "Set and See" dials on the camera body giving instant access to camera status information ? 

Photo 4 Natural Hold 1

Operating  Please refer to Part 10, Operating Systems and Part 12 Mockups, for detailed discussion.  The main operating tasks in the Capture Phase involve evaluating then adjusting as required, primary and secondary exposure and focussing parameters. All this needs to take place in a few seconds so the ergonomic design requirements are very stringent.

Primary exposure parameters are Time Value (shutter speed), Aperture Value (f stop) and Speed Value (ISO). Primary focussing parameters are Start/lock autofocus or Operate manual focus. Some cameras allow both simultaneously.

Secondary exposure parameters are exposure compensation and program shift (in P Mode). Secondary focussing parameters are autofocus area position and autofocus area size.

My research leads me to the conclusion that for a conventionally shaped hand held camera driven like a sports car by a practiced operator an excellent way to achieve smooth ergonomic flow for the above tasks  is as follows:

Left hand holds and supports the lens, operates zoom and operates manual focus if selected.

Right index finger operates four UIM's, controlling primary and secondary exposure parameters:  shutter button, main control dial, ISO and exposure compensation, without having to move a muscle of any other finger of either hand.

Right thumb operates two UIM's, controlling primary and secondary focussing parameters. These are Autofocus Start/lock (using a back button AF start module) or AF lock and Active AF area position/size (using a JOG lever).

Obviously there is no general agreement among camera makers or users that the schema detailed above is the best or even most desirable ergonomic solution to the camera control problem. But I want you to think about this: If you test drive a motor car which you have never seen before, you will be able to get in and drive it right away. No need to consult the instructions, cars have a steering wheel, pedals and hand controls which all work essentially the same way.  Camera designs are by comparison floundering about all over the place, with no general agreement on anything. If cars were designed like cameras every one of them would crash in about three seconds.  

However back to your camera, dear reader.  The questions you might want to ask include:  Can you easily see status indicators of primary and secondary exposure and focussing parameters in the monitor and/or viewfinder ?  Can you, while viewing the subject continuously in the viewfinder and without shifting grip with either hand, easily and smoothly adjust those parameters by feel without having to stop the process to look at one of the UIM's ?    Are the UIM's for Capture Phase adjustments located in High value areas of the camera ?  Are UIM's for Setup, Prepare or Review Phase located in high value positions, thus displacing Capture Phase controls to less desirable positions ? 

More generally does the process of making adjustments to exposure and focussing controls become second nature with practice allowing you to concentrate your attention on the subject ?  Or are there irritating roadblocks in your way every time you want to take a photo ?

Specific ergonomic issues 

* On /Off switch.  Over the years I have used cameras with O/I switches, levers and buttons all over the place.  I have found  that one of the best is a lever around the shutter button.  This allows the user to see or even better to feel, while carrying the camera, whether it is on or off and to change the setting by feel, using only the right hand, without having to look at the camera.

* The eye level viewfinder  Most cameras do not have one of these. However there are several circumstances where an eye level viewfinder is essential or at least highly desirable. In bright sunny conditions I have never yet encountered a monitor which allowed me to clearly see the image preview and all the camera data on or below the screen image.  Telephoto lenses and low light levels require the camera to be held steady, a task greatly helped by pressing the camera against the bones of one's head.   Eye level viewing helps the user separate from the distraction of his or her surroundings and concentrate on the subject. 

* Touch screen controls  These are very popular at the moment (May 2012).  I own and use several cameras with this feature, which I have subjected to careful ergonomic analysis. They are inaccessible and therefore useless with eye level viewing.  With monitor viewing they are accessible but involve getting fingers over the subject preview and disrupt holding. Furthermore it is cognitively disorienting to use one set of UIM's when eye level viewing but an entirely different UIM set when monitor viewing.  Tripod mounted is the only condition in which touch screen controls can be ergonomically harmonious with the process of image making.

* Lens based UIM's    Ring type UIM's work well on lenses for Capture Phase tasks. They are easy to locate by feel in landscape or portrait orientation and easy to operate with the left hand under or over the lens.  Buttons, sliders and levers can be appropriate for Setup and Prepare Phase adjustments where you can look at the UIM to operate it. Buttons and levers on lenses are extemely frustrating (because you can't find them by feel)  if you want to use them in Capture Phase and also want to use portrait orientation and/or switch from under to over holding. 

Photo 6 Forced Hold

* User interface module design  Please see Parts 4, Functional anatomy, 10, Operating Systems and 12, Mockups for discussion about this. The precise shape, size, configuration and position of UIM's is critically important for good ergonomics.

* Main control dial:  index finger or thumb ?    Some cameras locate the main control dial for use by the right index finger, others locate it for use by the right thumb. Some cameras have both, some have neither, some locate the dial where no human appendage could usefully reach it.  One recent camera release has three unlabelled dials each operated by the thumb with no dial allocated to the right index finger.  As with most things ergonomic there is obviously no general agreement. My research shows that the right index finger is the only finger which is allocated entirely to operating duties with no gripper duty at all. Logically it follows therefore that the right index finger is the most appropriate one to operate a main control dial.  Please note this ergonomic analysis is unrelated to  any person's likes, preferences or experience. For the record, I have owned and used cameras with main control dials in a variety of different places and have made mockups with the main control dial and other UIM's in a variety of places often moving them by as little as one millimeter to find the best location. My conclusion from this research is that:

IF, and it is a big if, the shutter button is optimally positioned, the best  location for a main control dial  is about 13 mm behind and at the same height as the center of the shutter button, angled to align with the position and movement of the right index finger.  A reverse configuration would also work well, in other words, switching positions of the shutter button and control dial.  

The two worst places I have encountered are: (a)  On the upper part of the front of the handle where the control dial is covered by the right middle finger and therefore inaccessible without completely releasing grip with the right hand.  (b)  Right under the thumb at  rest position which prevents you from holding the camera securely without bumping the dial.

If the camera has a well designed, configurable quartet of UIM's available to the right index finger and a JOG lever easily reached by the right thumb, then only one control dial is required.

Photos 1 and 2  ( NC indicates a button which could usefully be user configurable but which is not)  These illustrate an exercise in UIM   analysis of a camera based on photos of  the device and perusal of the user's manual.  This superzoom camera with 19 buttons and 2 dials,   is clearly aimed at the Level 4 user and will generally be used with the EVF, as maximum stability is required for the long lens.             There is a decent handle and a thumb rest which appears to be of adequate size. The area occupied by the Made in Japan words is the rest position for the thumb, properly devoid of any UIM's. So at least you can hold it properly without accidentally pushing a button or dial. The function of two buttons, fn1 and fn2, can be set by the user.  Unfortunately the other 17 buttons on this camera are not configurable and can only carry out functions preset by the maker. There are five buttons on the left side of the monitor. This is a satisfactory location for UIM's required in the Setup, Prepare and Review Phases. However 2 of them, ISO and AF are required in Capture Phase.  To use them the operator has to drop the camera down from the eye, take the left hand off the lens, press the button, return the left hand to the lens, shift  the right hand from the grip position, operate the control dial or four way controller, return the right hand to capture position then at last take the shot. If most of the buttons on the right side, particularly those in the highest priority zone adjacent to the shutter button and assigned to  +/-and Continuous shooting were user configurable, you could allocate ISO or AF to one or both of these and dramatically improve the ergonomic experience.  There are many other issues with this camera's HMI. There is plenty of space for a JOG lever but none is provided. There appears to be no option (I might be wrong about that) to assign AF start to one of the back buttons. 

This camera is large enough and has enough UIM's to have been capable of excellent ergonomics with more thoughtful HMI design and function allocation. Instead it represents a missed opportunity to create a really good user experience.

Photo 3, Set and See Dials  This camera has easily visible, quickly adjustable Set and See dials and levers on the top plate for adjustments in the Prepare Phase of use. This represents optimum ergonomic use for Set and See modules  All is not wonderful with this camera however. The red dot button, which is located in a high priority zone easily accessible to the right index finger,  cannot be assigned to anything other than movie start.  The silver button behind it does have user assignable function but is flush with the surface, making it almost impossible to find by touch. 

Photo 4 Natural Hold 1

This is a small camera with a Projecting Handle.  This type of handle works reasonably well on medium sized DSLR's, but shrinking the handle to fit a smaller camera does not shrink the hand which holds it. If the hand is held in the "Natural Half Closed" position as shown here the index finger does not fall onto the shutter button and the ball of the thumb is not on the thumb rest or the AEL/AFL button.

Photo 5 Natural Hold 2

The mockup shown here is actually smaller than the real camera but was designed around the "Natural Half closed" hand position. In other words the design process started from the hand and it's functional anatomy, not from any preconceived idea of style, shape or size. As a result it fits comfortably in that hand with the fingers exactly where they need to be to operate the key controls in capture Phase.

Photo 6 Forced Hold

In order to operate the camera in Photo 4 it has to be held this way.  This is ergonomically suboptimal with a weak grip and cramped hand position.