Kamis, 22 Agustus 2013

3 Way Holiday Camera Shootout Part 7, Ergonomics


Lumix G6 with 14-140mm lens
 
Summary of ergonomic concepts applicable to cameras   Ergonomics is the study of designing equipment and devices that fit the human body, it's movements and it's cognitive abilities.
Camera operation can be considered in four Phases, Setup,  Prepare, Capture and Review. Ergonomics devolves to Holding, Viewing and Operating in each of these Phases but particularly Capture Phase in which there is the highest requirement to carry out specific actions in a limited time.
General Observations  Each of these cameras offers at least acceptable ergonomics and none is without fault.
Holding  The lighter cameras are easier to hold than the D5200.  They require less constant support under the lens by the left hand and less gripping force by the right hand.  The D5200 and V2 each have a reasonable handle but a poorly located and shaped thumb support. The G6 allows the right hand to adopt a holding posture which is closer to the ideal "half closed, relaxed" position which I described in the post on functional anatomy of the human hand. There is enough space on the D5200 for a better thumb support which could be like that typically seen on Canon DSLR's. This would mean re-arranging control modules but that would not be difficult. I have also designed and built a mockup with the same dimensions as the V2 but with a much more user friendly layout.
Overall the most comfortable and secure kit to hold is the G6 followed by the V2 then the D5200.
Viewing  The modern electronic camera has complex viewing requirements. The user has to preview/review the image in the eye level viewfinder and also on the Monitor. In addition a user selectable menu of camera data must be visible on or beneath the eye level and monitor image. It is desirable that the viewfinder and monitor be configured to look the same and present the same data in the same format. This makes for a seamless segue from one to the other. In this regard, the mirrorless cameras have an advantage.
In my experience a fully articulating monitor (as found on the G6 and D5200) can be very useful. But performance with D5200 monitor view is sluggish.
In bright sunny conditions the D5200 optical viewfinder (OVF) provides the most appealing subject preview with the best shadow detail but the camera data can be almost invisible. Image playback is not available on an OVF.
In bright sun the G6 EVF is rather contrasty with blocked up shadows but the camera data are always easy to read.
The V2 EVF presents a slightly soft blue tinted image which is adjustable for brightness but nothing else. The V2 eyecup is a bit small, allowing light to impinge on the viewing eye, making clear preview difficult.
In Low light levels  The D5200 OVF gets quite dark. The EVF's on the two MILC's gain up in low ambient light to present a steady bright view in all conditions. In extremely dark conditions the G6 EVF is subject to jitter when panning but that is uncommonly seen in regular photographic practice.
In any conditions the very functional and fully articulated monitor of the G6 is  useful and practical. I have found that having become accustomed to this type of monitor on several Lumix cameras over the last two years I do not want to go back to a camera with less functional monitor live view or a non articulated or just pivoting monitor.
So the D5200 and V2 each have their viewing strengths but overall the G6 provides the best viewing experience, followed by the V2 then the D5200.

On the left, Nikon 1 V2. On the right my wooden mockup with the same dimensions.  This has raised shoulders and a completely revised user interface with JOG lever, providing excellent ergonomics.
Operating  Modern electronic or hybrid mechanical/electronic cameras (like DSLR's) are very complex machines. This poses a challenge to designers. How can they pack into the device the multitude of functions and capabilities which are expected these days while maintaining a user interface which ordinary humans can understand and operate efficiently ?
I will just mention some of the highlights and problems with each camera as a full discussion of operating characteristics would be too complex for this blog post. I have posted detailed discussion about analysis of camera operation in early posts on this blog.
 D5200  In eye level view operates reasonably efficiently.
ISO can be adjustable via the Fn button if it is so tasked. But the Fn button is difficult to locate by feel. The D5200 implements ISO/Auto ISO in a fashion which I find strange and frustrating. In the Shooting Menu, or My Menu if so allocated, you can select to switch Auto ISO On or Off.  If  set  On then you cannot set a specific ISO via the Fn button or the menu.  You have to switch Auto ISO Off.
In the other two cameras the Auto ISO setting is contiguous with specific ISO settings which is a much more coherent arrangement.
Exposure Compensation is available via the +/- button behind the shutter button. With some practice this is easy enough to find by feel.
Direct Focus Area control is available on the Multi Selector. This is easily accessible to the right thumb and this function works well, except that the active AF area is confined to the central part of the frame. MILC's can use the whole frame.
AF start can be allocated to the AE-L/AF-L back button in proper DSLR fashion. But this capability is oddly implemented. If AF start is allocated to the back button, it is disabled from the shutter button. I can more or less see the logic of this but in practice I find it irritating and I don't like cameras which irritate me.
If you want to adjust Image Quality, AEB, WB, Focus Mode, AF Area Mode, Meter Pattern or Flash Mode you have to stop using the OVF, lower the camera, open the monitor (if it was closed) press the [i] button, press the [i] button again then scroll around to your desired setting with the Multi Selector, make the adjustment then return to eye level viewing. This workaround is partly a consequence of operational constraints built into the basic SLR design and partly a result of the "semi-beginner-style" user interface of the D5200.
 Compare this to the G6  which can be user configured to be able to make a comprehensive list of adjustments by feel, while continuously viewing through the EVF.

Nikon 1 "V3" mockup being held in the right hand. I needed my left hand to make the photo. I rate this as being the smallest camera size which can accommodate a fully ergonomic shape and control module layout.
V2  The designers of the V2 have deliberately restricted the number and range of features, functions and adjustments available. This is not such a bad approach as it makes the camera the easiest of the three to set up and learn to operate effectively. It can manage most of the requirements of most beginner to enthusiast users. The dials are well designed and turn with the right amount of  resistance and clicky feel. The V2 is a vast improvement over the incomprehensibly crippled V1. The F button could be implemented much better if it was configured like the Q Menu on current Lumix cameras.
I have designed and built a wooden mockup camera having the same dimensions as the V2. This is a proof of concept exercise which shows that within the dimensional envelope of the V2 it is possible to design a fully featured pro style camera with excellent ergonomic efficiency.
G6  My interest in ergonomics was provoked by Panasonic's first "G-Micro" camera, the G1, which superficially looks like and is aimed at the same user demographic as the G6.  But I found the G1 to be a really frustrating thing to operate with many ergonomic deficiencies. The G6 shows that the details of user interface implementation are of the utmost importance. The G1 was, in my view, an ergonomic kludge while the G6 is a pleasure to use for the snapshooter or expert alike. Press the [iA]  button for  a simple point-and-shoot user experience. Or switch to one of the user control modes, access the Fn button options and build a camera with a sophisticated user interface designed to individual requirements.
All the functions which need to be adjusted in Capture Phase can be made with the eye to the viewfinder, by feel, without breaking the flow of image capture activity.
The downside of this sophistication is that the G6 is more daunting for the novice at the Setup phase of use.
So the G6 is the most efficient camera to operate, followed by the V2 then the D5200.
Comment about ergonomics, DSLR-vs-MILC  A well designed and implemented MILC can provide a streamlined, integrated user interface which no DSLR can match due to the presence of the flipping mirror. This was one of the very best ideas of mid 20th century mechanical camera design but it is unable to seamlessly integrate the complex requirements of a modern, multi view, multi function electronic camera device.
Sony tried to deal with this problem with it's SLT (Single Lens Translucent) range of DSLR style cameras. These cameras have a fixed mirror which allows about 60% of the incoming light to reach the sensor and the remainder to reflect up to the PDAF module in the hump. This technology does provide operational and ergonomic benefits over the standard DSLR type. However these cameras are forever stuck with a mirror sitting between the lens and sensor, blocking a substantial part of the light, gathering dust and preventing reduction of the flangeback distance. It appears from rumor sites that Sony will probably move it's entire interchangeable lens camera lineup to MILC type quite soon.

Ergonomics, ranking

1. G6/14-140mm

2. V2/10-100mm

3. D5200/18-200mm

Next, Video User Experience

 

3 Way Holiday Camera Shootout Part 6, Performance and Speed


D5200, 18-200mm lens. You can see the orange in this photo is bolder than in the photo below. The one below is probably more accurate.
G6, 14-140mm lens. Different aspect ratio from the M43 camera. Apart from this and the different color rendition I see little substantial difference between these photos.
 
Published Camera Tests  Many published camera tests just regurgitate manufacturer specifications and present this as an evaluation of camera performance. For instance I was recently reading a comparison between two cameras, one of which could shoot continuously at 9 fps, the other at 5.3 fps. The faster one was declared "better". But the reviewer just got this information from the spec sheets without testing to discover if 9 fps actually delivered any benefit over 5.3 fps.  Delving further in to the specs, it appears that both cameras claim to be able to do continuous AF, Continuous Drive at 4.2 fps. But again we have no idea how effective either camera might be in terms of the data which really matters, namely the percentage of frames in sharp focus.

Real World Performance Testing  I subjected all three kits to a series of tests, evaluating the relevant ones by checking the resulting photos at 100% on screen.
General remarks  All three cameras (Except the D5200 in Live View Mode)  delivered very good performance. I think most users would be well pleased with any of them. They each switch on and operate in a brisk and responsive fashion. A missed shot will rarely be due to any deficiency in the equipment.
Autofocus Speed  For this test I focussed back and forth between a near object and a far object, acquiring focus with a half press of the shutter button and waiting for the beep plus green AF area. I used the central area in each case. I did not fire the shutter.
Camera
Outdoors, dull overcast
focus actions per second
Indoors low light
Focus actions per second
D5200, OVF View
1.5
1.1
D5200, Monitor (Live) View
0.3
0.2
G6
2.2
1.3
V2
2.5
1.0

 Comment on Autofocus Speed   Outdoors the V2 is the AF speed champ, just beating the G6 by a small margin. The D5200 is by no means slow and will please most users but it can't keep up with the two MILC's.
Each camera slowed indoors but the V2 was slowed the most by low light. I believe this is because it switches from PDAF to CDAF in low light and Nikon CDAF is slower than Nikon PDAF.
Of the three the G6 was almost fastest outdoors and was the fastest indoors.
Turning to the D5200 in Monitor (Live) view mode we discover that the word "speed" does not apply in any sense at all. The camera switches from Phase Detect (PD) to Contrast Detect (CD) which does the "5 step dance" on every shot even when the subject distance has not altered. It goes eee...errr...eee...errr...beep (Yay! look at me, I did it !!) Presumably exhausted by this effort, the screen goes black for 2-4 seconds before the camera is finally ready to make the next shot. That might be just acceptable for landscape and similar work but the Monitor AF is error prone as well as slow. If this sounds bad it is better than the last DSLR which I owned which was a Canon EOS 60D. This thing did an eight step dance to achieve Live View focus and still made mistakes. I suspect that in most cases pre-setting focus distance by scale would be more satisfactory for Live View photography.
You may read opinions on the net by various photo sages that DSLR's focus faster than MILC's as if this were a statement of indisputable fact. My testing shows this is not so.
You may also read that CD autofocus is slower than PD autofocus. This is only true to the extent that CD AF in current model DSLR's  is slower than PDAF in those same cameras. CDAF in current model M43 cameras is very fast indeed, faster in fact than the PDAF in many DSLR's. It is also in my experience and testing, more consistently accurate.

D5200 with 18-200mm lens
G6 with 14-140mm lens
 
Shot to Shot Times  For this test I pointed the camera at a fixed target and in Single AF, Single Drive Mode, center AF Area, repeatedly pressed the shutter to make an exposure. The camera did not have to refocus between shots but it did have to confirm correct focus.
Camera
Shot to Shot time, seconds
D5200, OVF View
0.65
D5200, Live View
4.1
G6
0.5
V2
0.25
 

Comment on Shot to Shot Times  Like it's namesake in Peenemunde in 1944, the V2 goes like a rocket.  The G6 and D5200 in OVF Mode are by no means disgraced however and will suit most purposes just fine. The D5200 in Live View Mode is best suited to subjects firmly bolted down and immobile.
Continuous AF, Continuous Drive, Predictive Autofocus  For this round of tests I used cars driving along a suburban road and a person walking towards the camera at close range. The cars were in mixed light varying from sunny to shaded. The walker was in partly open shade  requiring a high ISO for adequate shutter speed.
The task for each camera/lens kit was to hold focus on the moving subject at 4 or 5 frames per second, and in the case of the V2, 15 frames per second.  The V2 has a huge buffer of 72 RAW frames at 5 fps. The G6 can manage 6 RAW frames before slowing, the D5200, 4 frames. So I used Fine JPG capture for all tests. With JPG files the G6 and D5200 could run off 50+ frames per run, more than enough for my purposes. I used single center AF Area, AF Continuous and a 95 MB/Sec card.  The D5200 and V2 were set at 5 fps, the G6 at M Burst which gave 4 fps. I ran the V2 at 15 fps in a separate test. The V2 is as far as I am aware the only camera at any price which can do predictive AF at 15 fps.
I set each lens at or near it's longest zoom position. I used the eye level viewfinder for all shots.
I used cars and the walker to be reasonably sure that each camera had the same task to perform in the same conditions, making the test fair. I did not test sports as this would introduce many uncontrolled variables.
I downloaded the resulting many hundreds of files and inspected each at 100% on the computer screen. I rated each as being Sharply in focus, Just out or Unsharp.
The User Experience  In reasonably bright light outdoors, the most pleasing camera to use in Continuous AF is the V2.  It has a muted shutter sound. The EVF appearance is that of continuous streaming video even though the camera is actually making stills. There is no perceptible EVF blackout. The image preview appears steady in the EVF.   The RAW buffer is huge. If you want, the camera can run silently at 5 or 15 fps with AF on every frame.
Next best to use is the D5200 which operates just like other DSLR's with a short blackout between each shot as the mirror flips up and down.
The G6 has the longest viewfinder blackout after each frame. It is usable and with practice the subject can be maintained in frame easily enough. It would be nice however if the Panasonic guys got the system in the V2.
Results 
Camera
Cars, Frames sharply in focus average over several runs
Walker, Frames sharply in focus. Average over several runs
D5200, 5fps
86%
95%
G6, 4fps
85%
93%
V2, 5fps
66%
76%
V2, 15 fps
65%
Not tested

 Comment on Predictive AF Results  Each of these consumer level cameras performed surprisingly well at predictive AF. All three cameras got a majority of frames in sharp focus.
The V2 is the absolute speed king however when we look at the percentage of frames in focus the other two perform a little better.
I found no significant difference between the D5200 and the G6 both of which performed at a level which would have been considered excellent in an expensive professional DSLR just a few years ago, and maybe even today.
You may read in the online photographic commentariat that
a) DSLR's do predictive AF better  than MILC's
b) MILC's are useless for predictive AF
c) Phase Detect AF is better for predictive AF than Contrast Detect AF
Each of these assertions is incorrect as to fact.
I think what is correct is that
a) Contrast Detect AF in DSLR's with PDAF optimised lenses is unsatisfactory for predictive AF. These lenses have  helical focussing mechanisms which were once considered fast but are really very slow compared to the direct drive AF mechanisms in modern M43 lenses.
b) The latest MILC cameras and lenses, particularly those for the M43 system can do predictive AF very well indeed. However M43  EVF refresh technology needs to be upgraded  to match that of the Nikon 1 system.
Performance Ranking  This is a bit difficult to determine due to the mixed results achieved.
The V2 is the nicest to use and is capable of the fastest shot to shot times and frame rates in good light outdoors where most predictive AF work will be done. But the percentage of sharp frames is not up to the other two.  In addition its speed drops substantially in low light indoors.
The D5200 works well and delivers a good result in all the test conditions (with eye level viewing).
The G6 does predictive AF  much better than some commentators and testers would have you believe. Some of these testers may have set the Autofocus  Mode on M43 cameras to "AF Tracking" which does NOT produce effective predictive AF.  Continuous AF is available with the monitor swung out, a handy feature not available on the other two.
In the end I have decided not to call a winner of the Performance /Speed criterion. Each does a good job but each has a different spectrum of capabilities.
The very fact that I am not able to call a winner with any confidence is actually very significant. Two years ago any mid range DSLR from Canon or Nikon would have easily outperformed any MILC.  It is intriguing to see how the march of technology has altered the balance between DSLR's and MILC's, or at least the Nikon 1 and M43 systems.
I have little doubt that MILC technology and performance/speed will continue to advance. But the DSLR has just about come to the end of it's evolutionary journey.  The main arena for performance advances in DSLR's lies in the Live View side of their operation. But any advances in that direction will potentially be of even more use to MILC's. I am thinking of Canon's incorporation of PDAF on every pixel of the imaging sensor, being introduced in Australia as I write on the EOS 70D. Canon wants it to improve smooth continuous AF during motion picture recording. But if the idea really works well why bother with all the mechanical paraphenalia of a DSLR ?  It might be even more suitable for a MILC.  

Next: Ergonomics

 

Rabu, 21 Agustus 2013

3 Way Holiday Camera Shootout Part 5, Picture Quality

G6 with 14-140mm lens

D5200 with 18-200mm lens

 
Technical Image Quality vs Picture Quality   There are several internet sites which publish data about camera image quality using technical terminology. A well known one is DXO Mark (dxomark.com). DXO reports overall image quality, Color Depth, Dynamic Range and Low Light ISO. DXO also reports a range of other technical measurements such as signal to noise ratios at various ISO levels. These measurements are made in highly controlled conditions in a laboratory style environment using test targets designed to reveal specific imaging characteristics.  I have no doubt these results form a useful part of an overall evaluation of the capability of a camera.  For want of a better term, I refer to the figures produced by this type of testing as "Technical Image Quality".
But when we use a camera it is never in a highly controlled environment. Real world use introduces many variables which intervene between the technical capability of a sensor and the final picture. I call this final result "Picture Quality".
Factors Influencing Picture Quality   Some of the factors which might and in fact often do influence actual output picture quality include:
* Camera Movement. Some users can hold a camera steady, others don't do so well. Some camera/lens kits are easier to hold steady than others.
Some cameras have Auto ISO algorithms which keep shutter speeds in the acceptable range for hand held use, others allow shutter speed to fall to levels which can cause unsharpness.
Some users watch their shutter speed readout and increase ISO setting if the shutter speed falls too low.
Some cameras/lenses have some kind of image stabiliser which can help steady the camera/lens unit.
* Lens quality.
* Exposure. Some cameras have exposure metering systems which allow highlights to become overexposed (blown out), others protect highlights assiduously.
* Color rendition. Cameras differ in the way they render colors.
* Focus accuracy.
* Aperture and depth of field. A camera with a large sensor will have to use a smaller lens aperture to achieve the same depth of field as a camera with a smaller sensor. This in turn requires a higher ISO setting and/or slower shutter speed both of which could have a negative impact on picture quality.
Real World test procedure  I made hundreds of photos of a wide range of subjects, shooting the same subject in the same light at the same time with the three kits. I used both the Auto setting and one of the P,A,S,M settings, usually Aperture priority. I used Auto ISO most of the time as that is what I and I suspect most users do. I noticed that each camera typically used a different Auto ISO setting and therefore  a different shutter speed.
Subjects were in bright sun, front lit and back lit, shady bright light, outdoors, indoors, in medium and low level lighting, natural and artificial. I shot people, single and groups,  landscapes and  buildings inside and out. I shot JPG and RAW files. I uploaded selected shots to the computer and compared images side by side on screen. I looked at JPG's, unmodified RAW's and RAW's processed to "best result" in Adobe Camera RAW 8.1.
G6 with 14-140mm lens

D5200 with 18-200mm lens

 
Defining Picture Quality 
* Color rendition    Some people like saturated colors, others prefer a more natural rendition which may be less saturated.  Cameras often differ in the way they place output colors in the spectrum. For instance one camera might render blues slightly cyan, another might render blues slightly violet. The accuracy of each can be measured with suitable test materials but the individual photographer might not be overly concerned with accuracy. The cameras in this test do render colors differently but I had a hard time deciding if any one of those representations was better than another.
* Highlight and shadow detail  It is easy enough to evaluate the amount of highlight and shadow detail in a JPG or RAW file on screen or in print. This is not the same as technical Dynamic Range which is measured in a specific way, generally by photographing a transilluminated step wedge.  I found that although the D5200 has a higher technical Dynamic Range, this was not reflected in actual pictures.
* Resolution/sharpness  I looked at resolution and sharpness in the center, at the edges and corners of test shots. I found that lens quality, focus accuracy and auto selected shutter speed had a big influence on sharpness.
* Noise  I looked at noise levels in each of the comparison photos.
The cameras on test, real world results  If you review the technical image quality data in Part 2 of this comparison series you will see that the D5200 scores best, followed by the G6 with the V2 scoring lowest on DXO Mark ratings.
You might expect the D5200 would easily beat the G6 for picture quality but that is not the case in the many hundreds of photos which I made for this comparison test.  However both the G6 and D5200 made better pictures than the V2 in almost all comparisons.
* Color:  There are differences in color rendition between the three cameras but I could not say one is better than the other. Another observer might have a preference for one or the other. For instance the D5200 typically delivers more saturated colors than the other two.
* Highlight and shadow detail: the D5200 and G6 are both very good and very similar. Even in subjects with a high brightness range I could not proclaim one to be better than the other.  By comparison the V2 suffers from less highlight and shadow detail than the other two when subject brightness range is high.
* Resolution/sharpness:  In the  frame center there was not much difference between the three kits. One might have expected the D5200 with a lot more pixels to excel here but that was not often  the case when actual photos were examined.  At the edges and corners the 18-200mm lens let the D5200 down,  producing consistently softer peripheral resolution than the other two lenses. The V2 in lower light levels often selected a low Auto ISO level presumably to keep noise levels in check. But this also produced a low shutter speed which fairly often led to unsharpness due to camera shake.
 I don't understand why the D5200 did not deliver better sharpness/resolution in the frame center. The 18-200mm lens works well in the center and the camera has more pixels than the others so one might expect it to beat the others easily. I did not have the time, money or motivation to test the D5200 with a better lens.
* Noise: The D5200 produces less noise at high ISO levels than the G6 which in turn is less noisy than the V2, which exhibits noise even at base ISO.  In actual photos the D5200 would typically set the highest Auto ISO level, followed by the G6 then the V2.  As a result the noise superiority of the D5200 was often countered by the higher ISO setting. With the camera on a tripod and with matched ISO settings the D5200 was able to demonstrate it's superiority. V2 pictures were always more noisy than the other two.
Summary My overall ranking for picture quality taking into account all the real world factors is:
1. G6/14-140mm.
2. D5200/18-200mm. With a better lens the D5200 would be the winner.
3. V2/10-100mm

Next: Performance

 

 

 

 

Selasa, 20 Agustus 2013

3 Way Holiday Camera Shootout Part 4, User Experience


Nikon 1 V2, 10-100mm lens at 100mm
 
Camera Reviews  Many camera reviews provide a long list of specifications and features. Several also provide a detailed description of all the various User Interface Modules (UIM, meaning buttons, dials levers, touchscreens etc), describing the location and function of each.  No doubt this "shopping list" approach to evaluation has it's uses but reviews like this leave the reader with very little insight as to whether the device is user friendly or not.
User Experience  In my family and I suspect many others, devices of all  kinds which do not work in harmony with the user get left in the drawer depreciating in value. If a camera is not user friendly it will not be used and so it's real world image quality and performance will be nil.
Notes on the single lens reflex camera  (SLR)     For 50 years SLR's  used film as the recording medium. There was no hint of digital capture, monitor viewing or motion picture capability.  With the advent of the digital era the SLR morphed into the DSLR but retained it's basic architecture and flipping mirror operation. Still  image and motion picture preview on the monitor require the mirror to be flipped up and locked. This blocks the optical viewfinder and exposure metering unit. It also disables the phase detect autofocus module beneath the mirror. So in monitor view the DSLR has to use a completely different system for exposure and autofocus, taking data from the imaging sensor itself, just like a MILC. In effect the modern DSLR is two cameras in one.
Notes on the MILC  Mirrorless interchangeable lens cameras were designed for all electronic operation from the start. Focussing, exposure and capture all use the imaging sensor. The camera works the same way with eye level or monitor viewing. This enables a seamless transition between these two viewing modes, either of which can be used for still and motion picture capture.
Monitor viewing and motion picture are fully integrated electronic functions of the MILC but are an afterthought to the SLR's basically mechanical operation.
In addition MILC's, having dispensed with the flipping mirror, mirror box and pentaprism  can be much more compact than DSLR's with the same sized sensor.
Price  Before  using a camera one has to buy it. The D5200/18-200mm  is sufficiently more expensive than the other two kits to give one pause about buying. If this camera had markedly better picture quality or performance than the other two kits this extra cost might feel justified.  The G6/14-140mm costs more than the V2/10-100mm but it does deliver better image quality.
Size, Mass   Although it is not terribly evident from the product comparison photographs, the D5200/18-200mm feels significantly more massive in use than the MILC's, which feel very similar.
Features  I have to confess being rather skeptical about many of the features which festoon modern cameras. This trio has some which could be useful and others the appeal of which eludes me. The G6 has touch screen operation, focus peaking and Wi-Fi connectivity to name just a few from the long list available. The V2 can shoot with predictive autofocus on every frame at 5 or 15 frames per second, a huge buffer and continuous streaming EVF view.  On the other hand the V2 has some faddish features which I suspect will be three day wonders for many users. These include Motion Snapshot Mode and Best Moment Capture Mode.

User Interface  For the novice or snapshooter each camera has an Auto mode. The D5200 has an additional Auto [No flash] mode. Auto Mode works well in each case, allowing easy point and shoot operation.
The D5200 allows user set function of the Fn button on the front of the camera. In practice this will likely be allocated to ISO as there is no other place for direct access to ISO adjustment. Unfortunately the Fn button is difficult to locate by feel as it is immediately adjacent to the lens mounting index marker and close to the identical flash pop up button.

The V2 offers a user interface with reduced content compared with the other two cameras. This might suit the less adventurous user quite well but could be frustrating for an experienced user. The V2 offers no control modules with user selectable function.

The G6 has by far the most user configurable control interface with 6 hard buttons and one lever all enabled for user selectable function. In effect the moderately advanced user can build the  interface to suit personal requirements, then change it as those requirements evolve over time. In addition the G6 has three Custom Modes where a group of user configured settings can be saved and reused at any time. This high level of user control does make the G6 appear somewhat intimidating for the novice wanting to move beyond iA mode. Making best use of  all that user control does  require some thoughtful consideration about how a camera works and how the individual user wants it to function.
Holding, Handling  The D5200 feels unbalanced, with a relatively heavy lens on one side and a somewhat inadequate thumb support on the other side. I found it always necessary to apply substantial gripping force with my right hand and also fully support the lens with my left hand. There is enough space on the back of this camera to fit a more prominent thumb support which would allow the right thumb to lie diagonally across the back of the camera for easier holding  with less gripping force.  The G6 achieves this with a smaller body, showing that it can be done. The V2 has a prominent handle and gets away with the poor thumb rest by being so small and light.
Operating  Both the MILC's offer seamless integration of stills and video, eye level and monitor viewing. The G6 allows the monitor view and EVF view to be configured to the same layout so the transition from one to the other involves no cognitive disconnect. The MILCs allow an extensive and user selectable list of camera data to be displayed on or beneath the EVF/Monitor preview/review image. The G6 offers the most options.
Both the MILC's operate smoothly and quietly. The mechanical shutter of the V2 is particularly unobtrusive. Both can be set for silent operation using an electronic shutter. The D5200 operates with audible whirring and clunking as the AF motor, shutter  and flipping mirror do their thing.
Family appeal  Part of my testing process has been to give each of the cameras to various family members to hold and use. None of them selected the D5200 as the camera they would like to take on a family holiday. Of the two MILC's, my pick for user experience is the G6 as it has the best ergonomics. But others selected the V2 for various reasons. It is the smallest and (just) lightest, it is the most quietly unobtrusive in operation and (this is not a joke) the shiny white surface is not easily marked by ladies' makeup.
My ranking for user experience is
1. G6/14-140mm
2. V2/10-100mm
3. D5200/18-200mm

Next:  Picture Quality

 

 

Senin, 19 Agustus 2013

3 Way Holiday Camera Shootout Part 3, Lenses


Nikon 1 V2 with 10-100mm lens
 

Introduction  Lens quality is a key determinant of overall picture quality. No camera can perform better than the lens mounted onto it.
Superzoom Lenses  These have the advantage of versatility and for most purposes, remove the need for changing lenses. But they have a complex design with many elements and at the consumer level as with the three lenses in this review, are built to a price. This means they do not deliver the same optical quality as less ambitious zooms and are more prone to sample variation and decentering.
Each lens extended to it's longest focal length. On the left the Lumix G6/14-140mm. In the center the Nikon D5200/18-200mm. On the right the Nikon 1 V2/10-100mm.  
 
Description
1. For the D5200 DSLR, we have the Nikon AF-S Nikkor 18-200mm f3.5-5.6 G II DX ED VR. Yikes, just the name of the thing takes almost a line of type. This is the MkII version of this lens, dating from 2009, although it has the same optical construction as the MkI version. This is a solid feeling, apparently well built lens with double extending barrel. It is the only one of the three to have  physical distance scale, located  beneath a transparent window in typical DSLR lens style. This means you can manually set a chosen focus distance by scale.
It zooms smoothly enough. The external barrel is bristling with switches for Zoom Lock, AF/MF, VR On/Off, VR Normal/Active. The zoom does creep without the lock. There is audible clicking and whirring from the lens as it focusses. Although by no means a large or heavy lens by DSLR standards it feels much more bulky and weighty  in the hands then either of the other two lenses.
It appears to be a parfocal design, which means it stays in focus while zooming.
2. For the G6 we have the Lumix G Vario 14-140mm f3.5-5.6  Asph Power OIS. This is a new for 2013 and completely different version of the Lumix 14-140mm lens. The original version dating from 2009 was larger, heavier, had a smaller aperture range of f4.5.8 and cost more on introduction. Early reports indicate the new version is also optically superior. Everything improved, Wow!  This is the lightest lens of the three and is only 4 mm longer than the Nikon 1 lens. It has a single extension inner barrel with the smoothest zoom action of the three lenses and no zoom creep. It has an OIS On/Off switch on the outer barrel. Despite it's light weight it feels well made with no detectable free play of the barrel, unlike the other two lenses which do exhibit a little movement.
It is a varifocal design which means it has to be refocussed after zooming.
3. On the Nikon 1 V2 we have the Nikon 1 Nikkor 10-100mm f4.0-5.6 VR. this is also a second version of the Nikon 1 superzoom theme. The original Nikon 1 10-100mm PD superzoom is a much larger and heavier lens with 72mm filter size, designed, I believe mainly for motion picture duties. Like the other two lenses this one feels very well made and operates smoothly although the double extension inner barrel zoom action does have a little hitch in it's progress about half way through the range. This lens is of semi collapsing type to reduce it's closed length. To extend the lens for use you press a button on the lens barrel then twist the outer barrel until it clicks. This action also switches the camera on, ready for action. This might sound a bit clumsy but in practice works well and soon becomes second nature. Unfortunately this lens does not have a manual focus ring just as all but one of the Nikon 1 lenses at the time of writing lack a manual focus ring. OOOps !! Did it not occur to the Nikon product development people that enthusiasts might be interested in a system camera which can do predictive AF at 15 frames per second ???
This is also a varifocal design.
Sizing Up
Lens
Min
Length
mm
Dia
mm
Box
Vol
cc
Filter
Dia
mm
Focal
Length
mm
Diag
Angle
View
Degrees
Mass
Min
Foc
Dist
Wide
mm
Min Foc Dist Long
mm
Nikon 18-200
97
77
575
72
18-200
76-8
565
250
460
Lumix
14-140
75
67
336
58
14-140
75-8.8
265
300
500
Nikon
10-100
71
61
258
55
10-100
77-9.2
298
350
650

 Comment on DimensionsAs you would expect, the DSLR with the largest sensor needs the biggest lens and the Nikon 1 V2 with the smallest sensor has the smallest lens. However the two MILC lenses are quite close in dimensions, while the jump up in size and mass to the 18-200mm is more apparent in use.
The Minimum focus distance is measured from the subject to the sensor plane.
Mechanical function  Each lens has optical image stabilisation which appears to work well. My subjective impression is that VR in the Nikon lenses appears to stabilise the viewfinder image more effectively than OIS in the Lumix.
Mirror Slap and Shutter Shock  I ran numerous systematic tests for these unwelcome phenomena, using shutter speeds from 1/10-1/400 second. In this range I found no evidence of blur due to mirror slap with the D5200 (mirror down) and no evidence of blur due to shutter shock with the D5200 (Live View) or the V2 with mechanical shutter. Nikon's engineers appear to have tamed shutter shock quite effectively.
With the Lumix 14-140mm on the G6 I did find evidence of shutter shock in the shutter speed range 1/100 to 1/160 second with the mechanical shutter.   There was no problem with the E-Shutter in use.
Decentering  With so many lens elements it is not surprising that they are not always assembled with absolute precision. Each of the lenses in this test showed some evidence of decentering, particularly evident at the long end in each case but also apparent at the wide end of the 18-200mm.
Manual Focus  There are marked differences in manual focus operation between the three kits.
Worst is the V2 which can do MF but the procedure is so convoluted and the  determination of In/Out focus so difficult, that the whole exercise is hardly worth the bother. You have to press the Feature  button, scroll to the Focus icon, press OK, scroll to MF, press OK again, then rotate the Multi Selector to change focus. Press the OK button again  to zoom in and rotate the Command Dial to zoom some more.
With eye level viewing the D5200 allows FTM (Full Time Manual, enables manual focus while autofocus is active).  This works well at the long end of the zoom but at the wide end it is almost impossible to pick the in/out  focus transition and there is no focus assist (no peaking, no electronic zoom). That is just a characteristic of  typical APS-C optical viewfinders. You get what you get.  In Live View the D5200 also offers FTM with the option to zoom in using the Zoom In and Zoom Out buttons. However it is still very difficult to evaluate the In/Out focus transition at wide angle lens settings. In addition you have to be very dextrous or better, use a tripod, to juggle the Zoom In/Out buttons while pressing the shutter button and operating the manual focus ring while supporting the camera and lens.
By far the best manual focus arrangements are to be found in the G6/14-140mm. First you have FTM with eye level or monitor view and it works the same with both. Just acquire AF with the AF/AE Lock button or half press the shutter button and simply start turning the focus ring on the lens. The view zooms in automatically and can be zoomed further by turning the rear dial. Focus peaking springs into action and makes picking the in focus position easy.
Or you can go to the Q Menu while using eye level or monitor view and select MF. This is easily done by feel without having to look at any of the buttons. Either way the process is fast and accurate.
The only thing you don't  get with any M43 camera to date is the ability to preset a chosen distance by scale.
Optical Performance
 Note that these results are valid for the lens samples which I tested. Due to sample variation different results could be given by other copies of the lenses.
Resolution   I ran many tests for resolution using a test chart and many real world subjects of different types, photographing the same subject with each kit side by side. I won't bore you with the minutiae of my findings but here is a summary of the results:
The D5200/18-200mm was best or equal best in the center at all focal lengths [except for issues with focus variation, see below]. This kit delivered the worst edge/corner performance at all focal lengths.
The G6/14-140mm was equal best (or better when the 18-200mm did not focus correctly) with the 18-200mm in the center on several of my test runs and was best at the edges and corners at all focal lengths on all test runs.
The V2/10-100mm was equal to the 14-140mm in the center on some runs and second to the 14-140mm at the edges and corners on most runs.
Overall the Lumix 14-140mm had the best all round resolution taking into account center, edge and corner sharpness at all focal lengths.   Next was the V2/10-100mm and  last was the D5200/18-200mm, let down by poor edge/corner performance.
Flare  Each of these lenses is prone to flare with the sun in frame and at or near the frame edge. This is normal for this lens type. In use each should be protected from sun on the front element, if possible.
Chromatic Aberration (CA) and Purple Fringing (PF)  These issues are quite common with superzoom lenses. The G6/14-140mm utilises automatic, in camera CA correction which is very effective to the extent that CA in photos from the G6  is almost nil. There is some residual PF in some very high contrast scenes.
The D5200/18-200 is very prone to CA and PF.  For RAW files there is a Profile for this camera lens combination on Adobe Camera RAW (ACR) (or Lightroom) which rectifies the CA quite effectively.
The V2/10-100mm is also quite prone to CA and PF but there is no profile at the time of writing. CA can however be removed manually in ACR.
Distortion  The 18-200mm and 10-100mm lenses have plenty of barrel distortion at the wide end. This is corrected with the ACR profile for the 18-200mm. The 14-140mm probably also has substantial distortion but if so it is largely corrected automatically in a M43 camera.
Focus Variation All autofocus systems are prone to error with some subject types. These are described in the D5200 Reference Manual although I couldn't find much about this in the G6 or V2 Manuals.  In the many hundreds of photos which I made during the comparison testing process, I found some frames incorrectly focussed, as indicated by center of frame unsharpness. The proportion of these not-quite-in-focus frames was higher with the D5200/18-200mm in both eye level view (PDAF) and monitor view (CDAF).
Summary   By the time my lens tests were complete a clear ranking had become apparent.
1. Overall the Lumix 14-140mm is the best lens of this trio, followed by
2. The Nikon 1 10-100mm, with 
3. The 18-200mm bringing up the rear.
Comment on the rankings  The Lumix 14-140mm is the newest design of the three, the Nikon1 10-100mm not quite so new but recently released. The 18-200mm is by several years the oldest.  It does appear that the design and manufacture of consumer zooms has improved considerably in the last few years.
And to finish on a little aphorism: "Dont judge a lens by it's size or price".
Next: The user experience