Micro Four Thirds for Sport & Action Photography

Sport / Action with Micro 4/3 Cameras

Author  AndrewS  August 2012

Introduction  Most mirrorless interchangeable lens cameras (ILC) including all Micro Four Thirds cameras to date  use  Contrast Detect (CD)  autofocus technology.   DSLR's in viewfinder mode use Phase Detect (PD)  autofocus.  Canon EOS-M,  Nikon 1 (and soon Sony NEX)  ILC's use both phase detect and contrast detect AF technology.  Until recently it has generally been the case that PD systems were best for following focus on moving subjects while CD systems were more accurate with still subjects. 

M4/3 and sport/action  I wanted to find out if current model M4/3 cameras could be useful for sport/action photography. For the tests I used two camera bodies,  Panasonic GH2 and  Olympus EM5, both hand held for all shots, viewing through the EVF. Lenses used were Panasonic 100-300 mm and Olympus 75-300 mm,  mostly at the long end. For the follow focus tests  I  made hundreds of photos of three subject types, (1) Motor vehicles driving steadily towards and away from the camera at about 60 Kph, (2) Board riders catching waves, (3) Junior soccer.

Note on M4/3 "Focus Tracking"  Focus Tracking refers to a technology by which the camera establishes focus on a particular part of the subject which is then tracked and held in focus even when framing alters. I set focus tracking OFF with the EM5. You can find this in  Custom Menu A >AF/MF >AF Mode > C-AF,  not [C-AF+TR].

With the GH2, I set the Auto Focus Mode Dial to [1 area focusing],  Not [AF Tracking].

Several published reviews of the EM5 have commented adversely about it's "Focus Tracking" performance. The capability we are really looking for here is "Follow Focus" which is not the same thing as focus tracking at all. I would guess that some of those adverse review findings may have been the result of setting focus tracking ON . This forces the camera to make extra calculations on every frame, thus slowing it down.

High Jump  Prefocussed manually on the bar

Sport/Action technique   With respect to focussing there are two separate and distinct approaches to sport/action. The first approach is to prefocus manually on a selected location and wait for  the action to reach that spot. This strategy long predated autofocus and is still very useful in many situations. Any camera capable of manual focus can be used. M4/3 is very suitable due to the accuracy of manual focus  with MF assist. 

The second approach is to engage continuous autofocus (Oly C-AF, Pana AFC) and Sequential (Oly) or Burst Mode (Pana) Drive, then hope the camera can follow focus on the moving subject. The remainder of this article is about follow focus tests and results.

Camera Settings  Below are the settings I used for all the tests. The GH2 has several set and see dials and user assignable function buttons so can be set up for action using the hard control  modules directly.  I find the best way to set up the EM5 is to register a Myset once all the settings are in place.

*Mode Dial >S, shutter speed 1/800s - 1/1000s

*Autofocus:  Panasonic>Focus Mode Lever > AFC, Auto Focus Mode Dial >1 Area Focussing.    Olympus>C-AF  (not C-AF +TR)

*Drive Mode:  Panasonic >Rec Menu >BurstRate >M (nominally 3 fps).     Olympus >Custom Menu C >Sequential >L, 3.5 fps and, note carefully  >Sequential +IS OFF >OFF  This double negative is a bit of Olympus obfuscation without which the menu would be easier to comprehend. Anyway set this item to OFF to make IBIS ON with Sequential drive.

If you set the Burst/Sequential rates any higher the cameras will not be able to provide CAF, IS and  EVF preview on each shot.

*Image Quality> JPG Large/Fine (not super fine)

*Image Stabiliser ON. I used Panasonic IS1, Olympus IS1.

*Auto ISO

*AF area. I used single area, center position. Standard size (green square) on the EM5 and second up from the lowest size on the GH2.

*Memory Card: SDHC SanDisk Extreme Pro 95 MB/sec.

Cars at 60 kph Frame 1 of 11 EM5 Oly 75-300 CAF

Cars at 60 kph Frame 9 of 11 All frames between 1 and 9 were sharp

Setup notes

*It is important to avoid anything which will slow the camera down, for instance  a slow memory card, Focus Tracking, RAW capture or copyright data on the EM5.

*Focus Priority vs Release priority. Both cameras allow you to nominate focus or release priority. For the GH2 this is in Custom Menu >Page 2 > Focus priority on/off.  Presumably Panasonic focus Priority off  is equivalent to Olympus Release Priority on. With the Olympus it is in Custom menu C >Release > Rls priority S(ingle) or Rls Priority C(ontinuous).  I was not sure what to set so I did the tests with Focus priority on for the GH2 and for the Olympus [Rls Prio S] >off and [Rls Prio C] >on.

*Image Review. Auto Review, found in Setup Menu >Page 2,  is automatically greyed out with the GH2 in burst mode. For the EM5 I set Rec View >off  in the setup menu.

*EM5 EVF frame rate. I set this to High in Custom Menu J. The instructions say "Set high to reduce display lag".

*EM5 Vivid Picture Mode. There is a view circulating on user forums that C-AF works best with Vivid Picture Mode set. This may be so but I forgot about it while testing so had picture mode on the default and never got to test the effect of Vivid setting.

*Readers please note, if you are unable to reproduce the follow focus results reported here, go through your Menu settings/button functions/SCP/QMenu settings  with meticulous care, item by item. You may have inadvertently set some item which interferes with the follow focus process.

Burst Rate  With the settings above and the shutter held down the following actual burst rates were recorded by stop watch using 20 frames per burst:

GH2 with Pana 100-300mm lens: 2.2 frames per second.

GH2 with Oly 75-300mm lens: 2.5 frames per second.

EM5 with Oly 75-300mm lens: 3.5  frames per second.

EM5 with Pana100-300mm lens: 2.3 frames per second.

I noted the shutter cadence was quite lens dependent.

With the Oly 75-300mm lens the EM5 went ...chup-a-chup-a.....(double sound)

Both cameras +Pana100-300mm lens went ......click-a-da-click-a-da....(triple sound)

There is some characteristic, I know not what,  about the Pana100-300mm lens which slows both cameras down and produces a different shutter cadence.

Overall the Oly 75-300mm lens on the EM5 body had the best burst rate.

Cropped frame GH2 Pana100-300 AFC

Cropped frame GH2 Pana 100-300 AFC

Results, detail  I made many sequences of shots in each setting and rated each frame as  [Sharply in focus] or [Almost, but  not quite sharp] or  [Out of focus].

Cars driving towards and away, bright sun on subject

GH2 with Pana100-300: Sharp 21%, Almost 75%, Out 7%

EM5 with Oly 75-300: Sharp 58%, Almost 28%, Out 11%

Surfboard riders, some cloudy, some bright sun

GH2 with Pana100-300: Sharp 40%, Almost 51%, Out 8%

EM5 with Oly 75-300: Sharp 60%, Almost 38%, Out 2%

Junior soccer, Dull day, rain threatening

I only tried the EM5 + 75-300  as it performed best in the previous tests. I made 205 shots of which 5 were sharp (2.4%) and 50 Almost (24%). The rest were out of focus.

Dull day EM5 Oly 75-300 CAF

Results, summary   Clearly the EM5 with Oly 75-300mm lens gave the best results.  I was quite surprised to see how well the Olympus held focus  on  motor vehicles at  60 kph. I made many sequences of 9-11 frames in which all but the last one or two were sharply in focus. I used no special technique at all, simply stood by the roadside, hand held the camera,  centered  the radiator grille in the frame, half pressed the shutter release button for about half a second to allow the camera to acquire focus then fully pressed the shutter release button and held it down until the vehicle filled the frame or more.  The surfboard riders were more distant and much less predictable in lateral movement but quite steady in their speed of approach to the camera. Junior soccer on a dull day was by far the most difficult test. There were constant changes of speed and direction with  players running in and out of the frame all the time. No surprise I got few keepers that day.  

Conclusion  Some ILC's still lack any useful follow focus capability but M4/3 is starting to close the gap between ILC's and DSLR's, while continuing to provide  more consistently accurate single shot AF.    The Olympus EM5 plus Olympus 75-300mm lens can be used for sport/action photography with the reasonable expectation of a useful  percentage of in focus frames.  Results are best with subjects in direct sunlight travelling at a steady speed towards or away from the camera.   

 

Micro 4/3 Shutter Shock Revisited [OMD-EM-5]

MICRO 4/3  SHUTTER SHOCK  REVISITED

OMD-EM-5  with Olympus 12-50 mm and Olympus 75-300 mm lenses

Author AndrewS

Introduction   In May this year I published on this Blog an article titled "Micro Four Thirds Shutter Shake Syndrome S.S.S."  This described the problem with several Panasonic and Olympus lenses on a Panasonic GH2 camera. I subsequently bought and have been testing an Olympus OMD-EM5 camera with Olympus M Zuiko 12-50 mm and Olympus M Zuiko 75-300 mm lenses.   I have also had time to consider the issue, which I now prefer to call "Shutter Shock" in more detail.  The problem is not specific to the Micro Four Thirds sysyem but can or might be found in any mirrorless interchangeable lens camera if certain conditions are met.

The SLR  and mirror slap   Single Lens Reflex (SLR) and Digital SLR cameras have a mirror which, when the operator is using the eye level viewfinder, flips up just before each exposure. So the exposure sequence is Press shutter release button >Mirror flips up >Focal plane shutter opens > Sensor is exposed > Shutter closes >Mirror drops down.   The flipping up mirror sends a shock wave through the camera which can and does cause blurred pictures. My tests recently with a Canon EOS 60D camera showed that exposures using shutter speeds around 1/4 - 1/8 second are the most affected by mirror slap. These shutter speeds are rarely used in hand held photography but they are often used with the camera on a tripod.   The fix for mirror slap is Mirror Lockup.  The fact that mirror lockup does fix the problem tells us that the disturbance caused by the shutter opening is generally not sufficient to cause blurred results in (D)SLR cameras.

Mirrorless Interchangeable Lens Cameras and Shutter Shock  MILC's have no mirror therefore no mirror slap. Unfortunately they have a potentially more troublesome problem which I call Shutter Shock.  In the case of a DSLR the focal plane shutter is closed at the start of an exposure sequence. But the shutter of an ILC is open until an exposure is made.  The exposure sequence for most ILC's is Press shutter release button > Shutter closes >Shutter opens >Sensor is exposed >Shutter closes > Shutter opens. The first shutter close action, prior to the sensor being exposed, sends a shock wave through the camera and lens  which can cause blurred pictures sometimes with double imaging. My tests and many user reports have identified a shutter speed range from 1/20 - 1/200 second as being affected.  These shutter speeds are commonly used in hand held photography which is the reason shutter shock is potentially more troublesome than mirror slap.  The actual risk of shutter shock and the exact shutter speed range affected vary considerably with camera and lens makes and models.  By the way, the second shutter close/open sequence also sends a shockwave through the camera but of course, this happens after the exposure has been made.  The actual amount of disturbance produced by an ILC shutter is less than that of a DSLR mirror. I tried to demonstrate the shock produced in a Panasonic GH2 by sticking a thimble containing water onto the hotshoe then firing the shutter. This produced no perturbation in the water at all. But I know this camera (and others) can cause shutter shock with some lenses at some focal lengths and shutter speeds. Why ?

Fast and loose,  Focussing     ILC's use contrast detect autofocus. This requires the focus module of the  lens to be racked back and forth several times very quickly to enable confirmation of the point of highest contrast. To improve focussing speed, modern lenses have very lightweight AF modules, designed to be driven back and forth directly (not on a helical mount), quickly and easily with tiny, low power electric motors.  In a word, they are loose.  In consequence these focus modules are susceptible to being shaken by any source of vibration or shock including the action of a focal plane shutter.

Fast and loose,  Image Stabilisers  A key feature of modern cameras is the incorporation of image stabilisers. There are two kinds. Optical Image Stabilisers (OIS), if fitted,  are located in the lens and involve compensatory movements of one lens group.  In Body Image Stabilisers (IBIS)  require compensatory movements of the whole imaging sensor unit.  Both types require that the active module, when powered up , is  located by electro magnetic forces and  not held in place by physical constraints.  This technology allows the IS module to respond rapidly to camera movements in the service of reducing the effects of camera shake.  But the flip sided is that the IS units are loose and, like AF units are susceptible to being shaken by the action of a focal plane shutter.

Shake and Rattle   You can easily confirm if your camera gear contains loose elements by shaking it. When powered off, most of the ILC gear I have used will rattle when shaken. Powering on will stop the rattle.   Some lenses, such as Panasonic models with OIS,  rattle when shaken side to side. Presumably this is is due to the IS unit which can move side to side but not front to back. Some lenses, including the Olympus Zuiko M 12-50 mm, rattle when shaken front to back. This, presumably is due to unconstrained movement in the AF module. The Olympus EM5 body rattles when shaken side to side (IBIS unit) but not when shaken front to back.   The Olympus Zuiko M 40-150 mm lens does not rattle at all but does  exhibit blurring from shutter shock at shutter speeds from 1/80 - 1/200 sec when mounted on the Panasonic GH2.

Shutter Shock with Olympus EM5      I tested this camera with two lenses, the  Olympus M 75-300 mm and Olympus M 12-50 mm.

Olympus M 75-300 mm   I mounted the camera/lens unit on a tripod, set the focal length to 300 mm and made a sequence of exposures from 1/8 sec to 1/400 sec. Settings were IBIS off, Timer delay at 2 seconds. There was clearly apparent blur with double imaging from 1/100 - 1/200 sec.  Unfortunately I did not test the effect of Olympus Antishock (A/S) with this combination before selling the lens.  The  implication from these results is that with A/S off,  hand held shutter speeds with this combination should be faster than 1/320 sec and on tripod shutter speeds should be slower than about 1/50 sec or faster than 1/320 sec.

Photo 1,  12-50 mm lens Antishock off

Olympus M 12-50 mm   With this lens on the EM5 and set to focal length 50 mm,  I made four test runs: ( 1) Hand Held,  IS1, Antishock off   ( 2) Tripod mounted,  IS off,  Antishock off   (3) Hand Held, IS 1, Antishock on [1/8 sec]   ( 4) Tripod mounted, IS off, Antishock on [1/8 sec].    Shutter speeds ranged from 1/10 - 1/400 sec.   In the first run there was clear evidence of blurring from 1/40 - 1/125 sec with double imaging at 1/80 and 1/100 sec. The second run,  on tripod, with IS and  A/S both off,  produced good but not quite excellent  results across the whole shutter speeed range.  The most interesting set of results came from the third run, hand held with IS and A/S both on. This run produced good results right from 1/10 sec with no evidence of Shutter Shock and remarkably, no evidence of camera shake either, indicating that the EM5 IBIS is very effective at low shutter speeds.  More surprising was that from 1/60 sec and faster,  Run 3 results (hand held A/S on)  were slightly sharper than the results from Run 2 (tripod A/S off).   I should make it clear that I was pixel peeping test chart photos at 200%, thereby discovering small differences in sharpness which would probably not be noticed in general photography.  Predictably, all the frames in Run 4 were sharp.

Photo 2, 12-50 mm lens Antishock on

The interesting conclusion which I  reached is that for all practical purposes and to avoid having to remember which shutter speeds do and which do not produce Shutter Shock, the best course of action is probably to set Antishock [1/8 sec]  permanently with this body / lens combination.  Antishock delivers obvious improvement with hand held use and  shutter speeds in the 1/40 - 1/125 sec range. It also provides a small but useful  improvement with tripod mounted use. Of course you also get the unwanted side effect that every shot has a built in 1/8 second shutter lag which does take some gloss off  this camera's otherwise excellent performance.

Just for comparison I ran the same test sequence with the Panasonic 14-45 mm lens on Panasonic GH2 camera.  Antishock is not available on this camera.  I found no convincing evidence of Shutter Shock at all, handheld or tripod mounted, OIS on or off.  The most I could say is that at 1/100 sec and 1/125 sec both handheld and tripod mounted there was a slight hint of unsharpness detectable only with obsessive pixel peeping at 200%.

How can Shutter Shock be prevented ? 

Individual strategies

1. Know thy enemy. Run tests  like the ones described above with your  present equipment.  Discover what if any combinations of camera body / lens produce Shutter Shock. You don't need a fancy test chart for the photographs, a newspaper page with large, small and fine print pinned to a board will do just fine.

2. Avoid the affected shutter speeds. For handheld use choose faster speeds.  On the tripod,  select either faster or slower speeds depending on the conditions.

3. Use Antishock if you happen to own an Olympus camera with this feature and don't mind the shutter lag.

4. Use e-shutter on the Panasonic G5  (No flash, static subjects preferred).

5. Avoid buying or test carefully on your camera body before keeping lenses reported on user forums to have shutter shock issues. These include the Panasonic PZ 14-42 mm and  Panasonic PZ 45-175 mm.

Technology discussion  It seems to me that camera designers have or might develop the following strategies to deal with the Shutter Shock problem.

1) Using a mechanical shutter  If the camera has a standard ILC four action (close/open/close/open) focal plane shutter then Antishock appears to work quite well. The way Olympus Antishock works is as follows: Press shutter release button >Shutter closes >[Delay period occurs] > Shutter opens > Exposure occurs >Shutter Closes >Shutter opens.

The delay period allows vibrations caused by the first shutter closure to dissipate. Apparently the subsequent shutter opening does not produce sufficient disturbance to blur the photos. I found with the EM5 that the minimum available Antishock  [1/8 sec] works just fine. I assume longer delay periods would also work but have not tested them. If you have an EM5 camera you can easily see anti shock working by firing the shutter without a lens attached.

Notes for Olympus EM5 users:  To set Antishock, go to the Custom [gears] Menu E [Exp/ISO] > Scroll down to the last item > Antishock  >Select a time > Press OK to confirm > exit Menus. This takes 26 button presses. Now press OK to bring up the Super Control Panel (SCP) > Find the Drive Mode sub panel. The standard panel has options for single, continuous, timer etc. Once Antishock is set the options are all duplicated so there is one set with, the other set without, a little diamond shape to the left of the drive mode icon. The little diamond shape indicates Antishock is active. This is how you switch Antishock on and off.  Leave it set to "on" permanently in Custom Menu E.

Note about Mysets   Make sure you have all settings including  Antishock exactly as you want them before registering a Myset.

2)  Using a hybrid mechanical/electronic shutter  a.k.a. Electronic First Shutter   Some cameras have this technology. With the shutter open, exposure is commenced electronically then terminated mechanically with the physical shutter.  The Canon EOS 60D uses  this shutter type in Live View Mode.  My tests show it is effective in preventing Shutter Shock, at least on that camera.  Other cameras also use this technology but I have not tested them.

3) Fully  electronic capture  systems with no mechanical shutter  I am aware of two types of electronic shutter systems, progressive and global.

Progressive a.k.a. rolling  The Panasonic G5 camera (which I have not personally tested)  has the option of using a progressive system. If I understand it correctly the mechanical shutter is held open and data is read out from the sensor as you would read the page of a book, line by line.  This should eliminate Shutter Shock and early reports from G5 users indicate that is the case. But progressive sensor readout is very much an interim technology. It cannot be used with electronic flash because the flash duration is less than the time it takes the system to scan the sensor. It is also unsuitable when there is movement of the camera relative to the subject. This situation causes bending or other distortion of straight lines or other recognisable shapes in the subject.

The "Global Shutter"   This is the holy grail of electronic shutters. All the pixels on the sensor are read out simultaneously.  It is silent, eliminates Shutter Shock, works with electronic flash and does not distort subject shapes with movement.  I don't know of any actual camera which has this technology yet and even the soon to arrive Panasonic GH3 is rumored not to have it.

The Global Shutter appears to be the ultimate solution to the problem of Shutter Shock and it can't come too soon for me.

Samsung NX 20 Ergonomic Review

AN ERGONOMIC REVIEW OF THE SAMSUNG NX20 CAMERA

Contender or Pretender ?

Moving forwards or slipping backwards ?

Author  AndrewS  September 2012

 Introduction    After many years using SLR's  then DSLR's as my main cameras I bought my first (mirrorless) interchangeable lens camera, a Panasonic G1, in 2009. I was not  pleased with the G1's ergonomics so in 2010 I bought a Samsung NX10 which provided a nicer handle and a more user friendly control layout. I used the NX10 later followed by the NX11 (a very mild upgrade) for the next 2 years with a variety of Samsung NX prime and zoom lenses. I made thousands of photos with these cameras which proved very reliable and user friendly. However Samsung's image quality, EVF  and performance failed to keep up with advances made by Panasonic and Olympus in the Micro Four Thirds group, Sony NEX and other manufacturers. So I switched back to M43 in the form of Panasonic GH2 then Olympus EM5 and a selection of zoom lenses.  Then the Samsung NX 20 became available in Australia at a realistic price so I bought one, along with the NX 18-55 mm kit zoom, NX 50-200 mm tele zoom and an NX16 mm f2.4.  While testing the NX20 I was able to compare it with my experience of the NX10/11 and side by side with the Panasonic GH2 and Olympus EM5.

Market Position and buyer expectations  Samsung is marketing, to the extent the imaging division does any marketing in Australia, the NX20  as their "Premium" interchangeable lens camera. As such I think potential buyers would expect it to have a level of image quality, performance and ergonomics at least equivalent to premium ILC's from other brands.

Target User Group  The NX20 has specifications (like the 20 mpx sensor, RAW capture, EVF and swing out monitor) which might appeal to the "Expert/Controller" experienced photographer but also has features (like wi-fi, smart filters and selective color) which might appeal to the broader, snapshooting, smart phone savvy group.  The risk for a camera seeking to appeal to many is that it may satisfy none.

Review Priorities  This is an ergonomic review so I will concentrate on ergonomics and issues relating to the user experience. However brief comment about image quality is appropriate as this too, affects the user's engagement with the camera.  You can read elsewhere all the details about specifications and features. I have not tested video peformance for this review. Neither did I attempt to use the Wi-Fi feature, although I wonder how useful it would be with the 33-34 MB RAW files which this camera produces. 

Image Quality 

Resolution is potentially very high, even extremely high according to some reports.  But top grade lenses are required for full realisation of that potential. Unfortunately only one of the lenses I tested (the 18-55 mm kit zoom) came close to revealing the sensor's resolution potential and then only in the central area of the frame at some focal lengths.

Noise   Uncorrected RAW noise levels (straight off ACR 7.1 at default settings)  up to ISO 3200 were slightly less than the GH2 and slightly more than the EM5.  At ISO 6400 the NX20 gives you the option of very high noise levels (with hi ISO NR off) or mushy JPEG like images (with Hi ISO NR on). Neither appeals. This camera's characteristic tone curve is relevant to it's noise performance. I shot hundreds of photos of a variety of subjects using the NX20, GH2 and EM5 side by side. The EM5 typically delivers lighter mid tones than the other two cameras.  The NX20 files often produce a histogram skewed to the left. These dark tones have to be pulled up with the sliders in ACR/LR. The problem is that most of the noise resides in those dark tones so pulling them to the right increases the overall appearance of noise to the detriment of image quality.

JPG images show signs of overprocessing with smearing of details and watercolor effect at higher ISO levels.

Dynamic Range  My somewhat informal but practical method of testing DR is to photograph a set scene with high subject brightness range and check how well detail is revealed in highlights and shadows.  This test ranked the EM5 best followed by the GH2 then NX20. I lack the technical expertise to put a number on DR but DXO rates the GH2 at 11.3 stops, so the NX20 appears to deliver less than that.

Note that I am comparing the NX20 which has an APS-C (28mm diagonal) sensor to two M43 cameras each having a 21.5 mm diagonal sensor. One (the GH2) is 2 years old and about to be replaced. The NX20 with it's larger sensor should easily beat the M43 cams on all measures of image quality but does so only for resolution.

Performance 

Speed:  Samsung's very first ILC, the NX10, was slow to write data to the memory card.  I coped with this because I wasn't in a hurry most of the time. But I did miss the ability to snap off a series of shots in quick succession or follow focus a moving subject. Several firmware updates improved matters slightly but successive NX cams steadily fell behind M43 in overall operating speed. The NX20 is Samsung's eighth NX camera. One might reasonably expect the world's biggest electronics mega corporation to have fixed this pesky little problem by now.  Unfortunately the NX20 runs just like my NX10 with the initial firmware. AF is slower than that on M43. Changing settings such as ISO brings up pretty screens and funky noises but is laggy compared to the M43 cams. But the main problem is writing to the memory card.  My tests show that using RAW capture with image review turned off and a Sandisk Extreme Pro 95 MB/sec card the following are the shortest shot to shot times I could  achieve, with AF and  preview between each shot.

Shot 1>shot 2 = 0.3 sec. Shot 2>shot3 = 3 sec. Shot 3>shot 4 =4 sec. Shot 4>shot 5 =5 sec. It takes 17 seconds to make 6 consecutive shots and for most of those 17 seconds one is staring at a blank screen waiting for the cam to get on with it's job. The processing light continues to blink for a further 6 seconds during which time if you dare to try and adjust anything you will get the dreaded "Processing" message.  By way of comparison the GH2 can make 6 shots in 3 seconds.

The NX20 is advertised as being able to make 8 shots per second but that is only possible if you don't want AF or preview between each frame. The camera will make 8 RAW photos this way then put up the "Processing" sign for the next 30 seconds.

Continuous AF with Continuous Drive produces 6 frames in 6 seconds with image quality set to JPG Large Fine. The Olympus EM5 can run at 3.3 frames per second with the same image size and quality and keep focus on moving cars in the process.

Autofocus: In Single Shot drive, Single AF, Selection AF, autofocus is accurate and reliable in a wide range of conditions. My NX10 and 11 went for almost two years and many thousands of exposures with an AF misfocus rate of less than 1%. If the NX20 uses the same technology I imagine it will be equally reliable.  It operates at a decent speed  although not quite as fast as the latest M43 cams. The active AF area can be easily shifted around the frame. Continuous AF with continuous drive is best forgotten. This cam's overall operating speed is way too slow for continuous AF to operate usefully.

Auto ISO:  This is poorly implemented. The camera routinely sets an ISO and therefore shutter speed too slow for the focal length in use. The camera "knows" this because it puts up the shutter shake warning hand but fails to take the obvious next step and shift the ISO up to a higher level. This is particularly frustrating because other cams regularly get it right.

Ergonomics   I will review this using my standard headings for the four phases of camera use and the three main tasks of Capture Phase. For further explanation about this please refer to my discussion under multiple headings elsewhere on this blog.

Setup Phase  This mainly involves making settings in a main menu. Samsung's menu system is a model of clarity which other makers might do well to copy. It has (almost) enough options to do the job and is clearly laid out with no need ever to scroll down more than one page. Menus and submenus are clearly displayed. The lack of a "My Menu" heading for frequently used items is disappointing.

Prepare Phase Adjustments in this phase are made by a combination of hard modules (buttons, dials, scroll wheels) and the Fn screen. The Mode dial is of standard configuration and works well. The combination 4 way controller with rear dial is one of the best I have encountered. It is of rocking saucer design with a sharply defined circumference making it easy to find and operate by feel, without having to look at the module.  It is a vast improvement on the Panasonic "five button" arrangement used on the GH2.  There are two buttons on the top plate, just behind the scroll wheel . One goes to Metering Pattern and cannot be reassigned. If you don't change metering pattern often this becomes a wasted button sitting on a high value piece of camera real estate. The same comments apply to the adjacent green button. This is a carry over from the days when Samsung shared a DSLR platform with Pentax. It is a kind of universal reset button the function of which cannot be user reassigned. I use it to recenter the active AF area in Capture Phase but it is difficult to locate by feel so I end up having to take the camera down from my eye to locate the button visually.

The Fn screen is one of the best I have seen on any camera. It is very clear, easy to navigate and use. But OIS is missing from the Fn screen and can only be found in the main menu. When Samsung put their iFn button on the lens barrels, they removed the OIS on/off switch and failed to provide an alternative quick portal of access to this control. The iFn button cannot be configured as a quick OIS on/off control either.

Capture Phase, Viewing  Viewing arrangements on the NX20 are generally good. The monitor is of the versatile swing and swivel type and provides a clear, sharp view of the subject. The EVF is big improvement over that on the NX10/11, providing a clear sharp view with good shadow detail. Colors tend to be a little desaturated.  Key camera data are displayed clearly beneath the image preview in both the monitor and EVF. The only way to identify blown highlights in preview and review is the histogram, which is not always easy to read clearly. The only real problem with viewing is the excessive (compared to the latest M43 cams)  blackout time after each exposure. The EVF eyepiece is reasonably well shaped to fit the anatomical curve of the orbit in landscape or portrait orientation, but a  rubber eyecup would make viewing more comfortable.

Capture Phase, Holding  The NX 20 has an integral handle of the parallel type which I have found to be optimal for a camera of this size.  (please refer to my discussions elsewhere on this blog)  There is a thumbrest of adequate size.  This is a more natural and comfortable arrangement than the "projecting handle with shutter button perched on the end" which you find on the Panasonic G1/2 GH1/2.  So far, so good. However the spatial dynamics of handles and holding are subtle. When Samsung changed from the NX10/11 shape to the NX20 shape they altered several key ergonomic dimensions. The swing monitor takes up more width, leaving less width for the "control panel" area on the right side. In addition the designers chose, for reasons known only to themselves, to lower the shoulder height of the camera body and to alter the contour of the handle. People with small hands might find the new design an improvement, but my average sized adult male hands find the NX20 slightly less comfortable to hold than the NX10. In addition the horizontal distance between the center of the shutter button and the top scroll wheel has gone from 13 to 14 mm. Insignificant, you might think but the sum total of these changes in my hands leads to a slightly more awkward  user interface.

Capture Phase, Operating   Operation is generally straightforward with no dramatic faults. Both scroll wheels are readily located by feel and work well.  Most actions in Capture Phase including change position and size of AF area, can be carried out by touch while viewing through the EVF.  There are a few things which could be improved however. There are two buttons which are difficult to operate when you want them but easy to bump accidentally. One is the new red (video) button sitting under the right thumb. This is inset with a raised lip surrounding the button, presumably to prevent accidental activation. But some reviewers (not me) report they did bump it inadvertently yet it requires a firm push with the interphalangeal joint flexed to make it work on demand. The red button does not allow user reassignment of function. I would prefer this button  to be moved 10mm to the left so the thumb is not sitting on it in the basic hold position. It could be made slightly more prominent thus easier to activate when required and allow user selected configuration from a wide range of options for those who do not routinely use video. I would use it for AF start/lock. The other problem button is the AEL button situated on the thumbrest. This is in exactly the same place as it was on the NX10 and has the same problems. I find I constantly activate this while carrying the camera in my right hand because my thumb lies right over the button. But when I want to use it in the Capture Phase it can only be reached by releasing grip with the right hand, taking the cam down from the eye and locating the button visually. The camera would be better served if this button were deleted altogether and it's functions made assignable to a button on the top plate. Good ergonomic practice strongly indicates that  camera makers should not  place buttons in this location.

iFunction:  I am entirely underwhelmed by Samsung iFunction which I discuss in detail on another post on this blog.

Review Phase  Image review facilities are very good. It is easy to jump from one enlarged image to the next with the rear scroll wheel.

Lenses  Over the last two years I have bought and used a total of 12 Samsung NX lenses as follows:

16mm f2.4 (1), 20mm f2.8 (2), 30mm f2 (1), 20-50mm (1), 18-55mm OIS (3), 50-200mm OIS (4).   Three of these were purchased new with the NX20,  the 16mm, 18-55mm Mk3, and 50-200mm Mk2, all with iFunction. Readers please be advised that there is considerable sample variation between lenses. You may find yourself in posession of one which is better or worse than those which I have tested.

16mm f2.4: My copy of  this lens delivered mediocre performance at all apertures with resolution lower than the not very exciting 18-55mm kit zoom.

20mm f2.8: My first copy of this was soft at all apertures with severe flare against the light. The second copy was decently sharp in the frame center but still had the flare problem.

30mm f2: This was the best NX lens I have owned with near perfect performance at all apertures.

20-50mm (non OIS): This came with a NX100 body. My copy was a decent kit lens, quite sharp at the wide end, less so at the long end.

18-55mm OIS:  I have had three of these. The first was a Mark 1 with plastic mount, without iFn. It delivered a very decent performance at the wide and middle section of the zoom range, going a bit soft at the long end. The second, a Mark 2 with iFn was the best with good performance across the full range of focal lengths and apertures. The third one was a Mark 3 with metal mount and the worst performance of the three. It had a rough zoom action and a peculiar distribution of resolution. It was sharpest at the wide end but with strange soft sectors in the frame the like of which I have not seen in a lens before. Soft corners. The long end delivered good resolution on the test chart (close up) but gave very soft pix of more distant subjects at all apertures.

50-200mm OIS: I bought and used four of these in an unsuccessful effort to find one with good mechanical and optical performance. The first one (Mark 1) had a sticky zoom but was decent optically especially at the short end where it was excellent. The second and third were Mark2 's with a nice smooth zoom action but mediocre optical performance especially at the long end. Number four, also a Mark2 was the worst. The zoom action felt stiff with flexing of the outer barrel of the lens and excessive free play. Optically it was soft on the right side at 50mm, soft on the left side at 100mm and soft all over at 200mm.

Summary of  my experience with NX lenses  I think that 12 lenses over two years is a sufficient basis for some conclusions. My experience indicates poor sample consistency since the start of the NX line, with a recent decline in mechanical and optical quality.

Minor irritations 

Memory Card:   The NX10/11, GH2 and EM5 all locate the memory card behind a dedicated flap on the right side of the camera. But with the NX20 Samsung put the card in with the battery. Bad idea. Worse, the card sits very close to the opened battery cover making it awkward to remove. I have dropped the card many times as a result.

Caps:  Samsung body and lens caps (the body cap is the worst) have bevelled edges, preventing the fingers from getting a proper grip on them. This makes them awkward to remove from the body, lens or each other.

Shoot without lens:  The promotional material for the NX20 makes much of the camera's ability to shoot at 1/8000 of a second (something which I don't recall ever wanting  to do)  due to the availability of an electronic first shutter. I have "E Shutter" in the menu set to "on" but I can't work out if it operates with the most commonly used shutter speeds because the shutter will not fire without a lens. I do hear four distinct shuter sounds with the slower speeds indicating that E Shutter is probably not active at those speeds. Who cares? There is a phenomenon which I call "Shutter Shock Syndrome" (see my report about it on this blog) which does affect the NX cameras and which might be eliminated if E Shutter were available at all shutter speeds.

Conclusion   At the start of this review I put  two questions which the NX20 needs to answer.

1. Is the NX20 a contender for serious consideration by the expert/enthusiast photographer seeking high performance from a flagship camera and lens system ?  In a word, no.  The NX20 cannot match the latest offerings from M43 with regard to image quality, performance, ergonomics, lens selection or lens quality.

2.  Does the NX20 move the NX system forwards or backwards, relative to it's competitors ? In my assessment, backwards. Samsung is gradually improving it's camera offerings (but not the lenses at present)  but in piecemeal fashion so every time the NX cams move forward, the opposition has moved further.

Comment and opinion  I really don't understand why Samsung bothers with NX series cameras. They make about 200 million !!!!!  smart phones per year. Output of NX cameras last year has been reported at about 100,000 units which is 0.05% of the smartphone production.  Maybe Samsung wants to be  a player in every imaging sector.  The NX line at present is long on attributes which are secondary to the process of making good photos (cute looking bodies, special effects, funky colors, i-function, wi-fi) and short on imaging fundamentals (image quality, performance, lens quality). Samsung's latest camera releases, significantly branded "Galaxy" appear to be hybrid smart tablet/camera devices with an emphasis on connectivity. It would appear this is the way Samsung is headed with it's imaging products.