Lumix GH3 Review Part 9, Stop The Shakes

LUMIX GH3 REVIEW PART 9,  STOP THE SHAKES

How to get really sharp photos handheld or on tripod

Author  AndrewS  April 2013

Circular Quay Sydney. GH3 with 35-100mm lens on lightweight tripod, 1 sec @ f4.  Shutter Delay used. This frame is sharp but several others in the sequence were slightly unsharp due to the breeze causing camera movement on the light tripod.

Introduction  SLR and DSLR cameras can produce unsharp photos at certain shutter speeds due to a phenomenon called "Mirror Slap". The flipping mirror shakes the camera as it lifts up just prior to the exposure. DSLR's avoid the problem by using mirror lock up. Mirrorless ILC's have no mirror slap of course but they do have a potentially even more troublesome problem which I call Shutter Shock.  The standard mechanical shutter on a MILC cycles through four movements with each exposure, like this:

Press shutter button>Shutter Closes>Shutter Opens>.....Exposure Occurs...>Shutter Closes>Shutter Opens.

A DSLR shutter only has 2 movements in SLR viewing mode, The sequence is: Press Shutter Button>Mirror flips up>Shutter Opens>....Exposure Occurs...>Shutter Closes>Mirror drops.

Shutter Shock    It appears that the initial MILC Shutter Close  action sends a shock wave through the camera and lens which can cause unsharp pictures typically in the shutter speed range 1/20 to 1/200 sec. Not all lenses are affected and some lenses are affected more than others. I have written about this at length in previous posts on this blog in May and September of 2012. The mechanical shutter also produces a small but palpable shock from the first Shutter Open action. Does this also degrade image quality ? I don't know but presumably it is less a problem than the shutter close action.

The camera makers know all about it but they have not, as far as I am aware, referred  directly to the problem in their communications to consumers or in the published owner's manuals. I find this most disappointing. If they openly acknowleged there is an issue and engaged consumers with information about effective strategies to deal with it they would make many friends, I feel sure.  Failing to deal openly with problems is a sure fire way to alienate actual and potential customers. I would very much like to see Panasonic and Olympus come out and discuss this matter frankly.

However since it seems that is not happening, I hope this little article fills the void and will help you  Stop The Shakes and fully realise the imaging potential of your GH3 (and other M43 cameras) and lenses.

A recent reminder  I have recently been using and testing the Lumix 35-100mm f2.8 lens which is capable of extremely sharp results but only if used in such a way as to allow the lens to deliver it's full potential. More about that when I publish the lens test but it mostly consists of achieving exactly correct focus and making sure the camera is still at the point of exposure.

Palm Beach, Sydney. Lumix G5 with Lumix 45-150mm lens, hand held, OIS on. I included this to show that very high quality results can be obtained even with a middle level camera and budget zoom lens.

Hand Held Camera

Techniques  There are several camera work techniques which increase the likelihood of sharp photos. They could apply equally well to any camera.

* Slow down.  Hold the camera securely but not tightly. Do a little muscle relaxation exercise before a photo session. Mini meditate with some slow breaths in and out to slow the pulse and reduce muscle tremor. Look through the eye level viewfinder which helps stabilise the camera. Achieve focus with back button or half press of the shutter button. Breathe in, then out and smoothly squeeze the shutter button at the point of maximum exhalation.

* Manual focus if the subject and circumstances permit. Think about which part of the subject should be the focus point. Think about depth of focus and aperture required.

* Use the optimum aperture of the lens.

* Watch the shutter speed readout in the viewfinder and change ISO as required to keep it at or faster than the reciprocal of the lens focal length x 2.

If your lens is or might be one of those subject to the shutter shock problem, avoid shutter speeds in the 1/20 to 1/200 sec range.

Don't know if your lens is one of those ? Try asking a question on dpreview.com Micro Four Thirds Talk Forum, or one of the Mu-43.com forums. Somebody will know.

Crop of the photo above. The time is 1045.

Technologies

* Optical Image Stabiliser (IBIS in Olympus cameras) There has been much debate on M43 user forums about the value of  OIS, with some users and reviewers reporting a degradation of image quality at some shutter speeds and some lenses with OIS switched on.  There appears to be no general consensus about this so I generally leave OIS  ON for hand held photography. Some users routinely leave it  OFF.  Be aware that neither OIS or IBIS are truly OFF when the camera is powered up. The Image stabiliser module, which is  either a lens group in the case of OIS  or the entire Sensor module in the case of IBIS does not assume correct operating position until it is powered up continuously. It is held in the correct place by electromagnetic forces not mechanical restraints.   I can only suggest you conduct your own experiments if you think there may be a problem with the OIS on one of your lenses.

 * E-Shutter is, at this time,  available on the G5 and GH3 cameras. E-Shutter eliminates shutter shock but has some side effects and causes some limitations to camera performance.

E- Shutter is an electronic process which scans the image frame line by line in 0.1 seconds, something like an electronic focal plane shutter moving up the sensor reading out one line or group of lines (I don't know which) of pixels at a time.  As a result if the camera is panned horizontally or the subject moves horizontally during the exposure the shape of the object becomes distorted.

Images made with the E-Shutter can show alternating horizontal lines of light and dark with certain pulsing light sources which interact with the scanning action of the E-Shutter. I have encountered this with fluorescent lights but I believe other types can have the same effect.

E-Shutter limits available ISO to 1600, I have no idea why.

E-Shutter limits the longest available shutter speed to 1 second.

Flash is not possible.

Apart from all the above it works really well and I find that in many situations it is my preferred shutter type. I have it allocated to the Fn5 button on the GH3 for quick access. For further information about E-Shutter see http://m43photo.blogspot.no  

Luna Park, Sydney
GH3, 35-100mm lens at 100mm, 1 sec @ f4. Lightweight tripod. Shutter Delay, 2 sec. You can see individal rivets on the Harbour Bridge 900 meters from the camera.

Tripod Mounted Camera

Techniques

* Understand the relationship between aperture and depth of focus.

* Focus manually where possible.

* Use remote or delayed shutter actuation, see below.

* Avoid shutter speeds between 1/20 and 1/200sec with the mechanical shutter.

* Switch OIS  OFF.

* Never forget the benefits of the proverbial Sturdy Tripod.  I was doing some evening shots in the city recently using a lightweight Velbon Max i 343E (0.9 Kg) tripod, which I selected because I did not want to carry the larger Velbon Carmagne 630 with it's sturdy, ancient and long out of production Manfrotto 3 way head (1.9 Kg). There was a light breeze that evening which was enough to cause several of my shots with the Lumix 35-100mm lens to show definite signs of camera movement. There is nothing wrong with the Max i 343E in calm conditions, it's one of the best sub 1Kg tripods ever made, but in wind, there is no substitute for size, rigidity and mass. 

Technologies There are three ways to achieve indirect shutter actuation.

* Wireless, via Wi-Fi using a smart phone.

* Wired shutter release cable, DMW-RSL1, genuine Lumix or copy, they all seem to work OK.

* Self Timer. I usually find 2 seconds delay is sufficient.

* E-Shutter works well on the tripod, but is not available for exposures longer than 1 second.

* Shutter Delayis a new feature on the GH3, not seen on previous Lumix cameras. You find it in the [Rec Menu, page 3/6].  Shutter Delay cannot be allocated to the Q Menu or to a Fn button. You can however include it in a group of settings allocated to a Custom Mode. It works as follows with the mechanical shutter:

Press shutter button or activate shutter by self timer or wired or wireless remote> Shutter Closes......The set time passes......Shutter Opens>......Exposure Occurs......Shutter Closes>Shutter Opens. 

Shutter Delay can be set to 1, 2, 4, 8 seconds or Off.  It works  like Antishock on Olympus cameras but with a longer time delay. The briefest delay available with Olympus Antishock is 1/8 second.  The purpose of both technologies is to allow vibrations from the first shutter closing action to dissipate.

You can combine Shutter Delay with one of the indirect shutter actuation methods.

Note that Shutter Delay is also compatible with E-Shutter. In this case it delays exposure by the set time after actuating the shutter button, directly or remotely.

All this leads to two suggestions for operating method with the camera on a tripod.

Method 1, Shutter Speed less than 1 second.  This method gives a stable camera without the need for a wired or other remote.

* Timer 2 sec delay [Drive Mode set and see dial]

* E-Shutter ON. [Allocate to Q Menu or a Fn Button]

* Press the Shutter Button.

Method 2, Shutter Speed Greater than 1 second.  This method also allows stable operation without remote shutter actuation.

* E-Shutter OFF

* Drive Mode to Single Shot.

* Set the Shutter Delay to preference, 2-4 seconds is generally satisfactory.

* Press the Shutter Button.

To streamline access to the Shutter Delay setting, you can prepare the camera before the shooting session. Set [Menu Resume] ON, Setup Menu, Page 4/6. Next go to Shutter Delay in the Rec Menu, Page 3/6. Leave the setting to OFF until you need it and close the Menu Screen. Then when you next go to Rec Menu, it will open at Page 3 with Shutter Delay already selected ready for you to change.

Technology not found in M43 cameras  Some cameras offer the so called "Electronic First Shutter" technology. If I understand this correctly exposure is started electronically and ended mechanically. I have tested this in a Canon EOS 60D and found no evidence of shutter shock with live view shooting. I have no idea why it is not offered in M43 cameras. Patent issues ?

 One day, I hope to see the advent of the long hoped for "Global Shutter" a technology which promises to make most of the complicated strategies in this article redundant.

Summary  Extremely sharp photos can be made with the GH3 and other M43 equipment. The percentage of sharp shots will increase if the techniques and technologies described here are used.

Lumix GH3 Review Part 8, Image Quality

LUMIX GH3 REVIEW PART 8  IMAGE QUALITY

Good enough for almost anything

Author AndrewS  April 2013

Evening in Sydney. The GH3 has done a good job with long exposure and extreme subject brightness range. Only the streetlights and headlights are blown out.

Introduction  Early 4/3 and M43 format cameras struggled with image quality plainly inferior to that available in cameras with APS-C sensors, both DSLR's and Mirrorless ILC's.

Sony to the rescue  With the EM5, Olympus used a sensor made by Sony in preference to previous sensors made by Panasonic.  The result was an immediate improvement in image quality. Olympus used the same sensor on subsequent Pen models and the Lumix design team is rumored to have used the same sensor on the GH3.

Good enough image quality  Regardless of the origins of the sensor, most reviewers find the image quality of the GH3 to be  the same as or extremely similar to that of the EM5.  Most users posting  impressions of personal experience appear to indicate they find the GH3 image quality good enough for most purposes. My own experience is that this is the first M43 camera which I will take with confidence into almost any photographic situation having a high level of expectation that the photos will be correctly focussed and exposed and deliver good enough image quality for magazine reproduction at the very least and often good enough for large poster size prints.

Snow Cones, anyone ?  With help from ACR, the GH3 has retained detail in the clouds, the little girl's hat and the lady inside the shop, albeit with quite a bit of  grain visible on her face.

Comparison GH3-vs-GH2-vs-G5   I won't bore you with a lot of grainy pictures of books on shelves which is what I used for my basic comparison testing. A summary of the results is:

* Looking at RAW conversions straight from Adobe Camera Raw 7.3, I found that in the ISO 3200-6400 range, the GH3 advantage over GH2 was about 2/3 stop less noise. The GH3 advantage over G5 was about 1/2 stop less noise.

* I also found that the default RAW conversion by ACR produced files with noticeably different mid tone and shadow brightness. The GH2 files were the darkest in the mid tones and shadows, and the GH3 files lightest in the mid tones and shadows. The G5 tone curve lay between the other two.  The point here is that to adjust a GH2 file to match a GH3 file in mid tone brightness, I had to use the sliders in ACR to lift the darker tones. Those darker tones contain most of the noise. So the final outcome is that the GH3 improves on the GH2 by one stop of noise in the ISO 3200-6400 range and is 2/3 stop better than the G5.

* Highlights are less often blown out with the GH3 than the other two.

* GH3 colors are more accurate right across the ISO range than the other two.

* Resolution is the same with all three cameras.

* If a particular photo requires substantial highlight and/or shadow recovery in ACR, the GH3 files cope with this better than the other two cameras with less artefacts at the bright end and less noise at the low end.

iDynamic and iResolution  These functions appear as active in the Rec Menu with RAW or JPG files. With JPG files iDynamic applies a negative exposure compensation to the normal exposure for that scene then lifts the dark tones for an end result having better detail in both light and dark tones than a standard single exposure. With RAW files iDynamic just applies the negative exposure compensation and nothing else.

I ran a number of tests with iResolution on different scenes and have to confess I never quite convinced myself that it did anything that I could see.

Dynamic Range  I lack the technical expertise to evaluate this scientifically. In general photography in conditions with high subject brightness range there does appear to be a slight advantage to the GH3, but it is subtle.

I rarely need to resort to HDR strategies with the GH3, even in conditions with very high subject brightness range. There is almost always enough information in RAW files for ACR to give me a satisfactory level of detail in shadows and highlights.

Watching Telly, ISO 6400.  As usual, with help from ACR, the colors are reasonably accurate, surprising given the mixed nature of the light sources,  grain is moderate and detail quite reasonable for a high ISO shot.

High ISO  With judicious work in ACR I find even ISO 6400 files good enough for magazine reproduction with most subjects.

Summary  You can look up all the technical data at  dxomark.com  or  dpreview.com  and I would  recommend that anyone with an interest in image quality do so. However from a user's perspective the GH3 does a fine job right across the spectrum of imaging conditions from low to very bright light and low to very high subject brightness range.

Lumix GH3 Review Part 7, Ergonomics

LUMIX  GH3 REVIEW PART 7  ERGONOMICS

Holding, Viewing, Operating

The best M43 camera yet but can improve further

Author AndrewS  April 2013

GH3 Rear view

Introduction   The Lumix design team has been gradually improving the ergonomics and user interface of it's G-with-built-in-EFV cameras since the original G1 of 2008.  In fact the G1 design triggered  my interest in camera ergonomics and led to the creation of this blog. The G1 was so awkward to use I sold it and spent two years with a Samsung NX10. This camera was some way from ergonomic perfection but had a more user friendly basic design and layout than the G1. The GH2 delivered clear ergonomic improvements, with further upgrades in the G5, leading to the GH3 which represents a big step up in holding and operating compared to previous Lumix models.

Elements of ergonomics  In this article I will discuss Holding, Viewing  and Operating.

Natural half closed hand position. The hand takes this position with minimal muscle tension. The ideal camera will be designed to fit into this hand position. The GH3 comes close to that ideal.

Holding  The GH3 is 20% larger than the GH2 by box volume. This has allowed the designers to use a completely different handle and thumbrest design which conforms much better to the natural shape of the adult hand.  Human hands have not changed shape in the last 20,000 years. Camera designers just needed to adapt their products to fit the hands which use them, not the other way around.  With the GH3 they got it right. At last. Better late than never. Holding this camera feels very comfortable and secure, without strain.

Right index finger on shutter button.  The hand position is close to ideal.

Shutter buttonThe center of the shutter button is now inset 27mm from the right side of the handle.  This allows a more natural index finger position than on previous models.  The GH2 shutter button is only inset 15mm.

These numbers and descriptions will not mean much until you have a chance to hold these cameras and play with them for a while when the benefits of the new design will become readily apparent.

Right index finger on front dial. The finger moves easily onto the position required to operate the dial.

Right index finger on the ISO button. Here the index finger has to stretch to it's maximum angle away from the middle finger in order to reach the ISO button.

Viewing  I discussed the GH3's EVF at length in Part 2 of this series. Over the years I have used fixed, swing up/down and fully articulated Monitors. The GH3 uses the fully articulated type which I find to be the most versatile and useful. You can hold the camera at waist level in landscape or portrait orientation, hold it at low level or above the head. The Monitor readily enables all these shooting positions.  It can also be turned inwards as seen in the photographs to prevent damage to the screen when carrying the camera or using the EVF.

Transition from eye level to monitor viewing is seamless, with the same information presented the same way on both viewing devices. Both provide a 100% accurate view. Both can be set up to provide key camera data on or beneath the image preview. Both can be configured with maximal or minimal data overlay at the press of the Disp Button. You can have an electronic 2 axis level guide, histogram, Expo Meter display, choice of grid lines, etc...etc.  

The GH3 allows the user to clearly see readouts for the primary and secondary exposure  and focussing parameters. It has the control systems in place to allow each of these to be quickly and easily adjusted.

Rear view. Thumb in comfortable hold position, angled across the back of the camera not squeezed up on the extreme right side as required by some cameras.

Rear View. Thumb has been moved across onto the rear dial which it can operate without having to flex the interphalangeal joint. This maintains a stable grip on the camera with the base of the thumb.

Operating  Overall this camera provides a very well designed user interface allowing fast accurate operation.

Set and See Modules  The On/Off switch, Main Mode Dial, Drive Mode and Focus Mode functions are all on set and see modules. These allow the user to see at a glance and change as required, without having to turn the camera on which Main Mode, Drive Mode and Focus Mode is set.

Operating the Control Dial. This is no different from other cameras having a 4Way controller/Control Dial in this position. It is workable but disrupts grip on the camera with the right hand.

Mode Dependent Scroll Wheels  These are the Front (top) Dial, Rear (upper) Dial and Control (rear lower) Dial. These are a huge improvement from the arrangements on previous G, other M43, and indeed most DSLR cameras which I have used.  The first thing you will notice is that there are three scroll wheels. To a user unaccustomed to this many, three may seem overkill but in practice works extremely well. I was previously a proponent of the single scroll wheel approach but having used the GH3 I am now a convert to the multiple scroll wheel system.  It allows users to select whether they want to use the front or rear dial for routine adjustments such as changing aperture in Aperture Priority Mode.

Location  At last they put the front dial in the right place !!  which is just behind the shutter button. The dial is well positioned, 12mm behind the center of the shutter button and slightly angled down and across the camera body. 

The rear dial has also arrived at the right place, where it can be operated by the thumb without having to flex the interphalangeal joint. At last, they got it right. Excellent !!

The Control Dial is now large, has knurled edge and is easy to find and operate by feel. Some reviewers have complained that in their (successful) efforts to prevent accidental activation the Lumix designers have recessed this dial a little too much. I can see their point but I have found that with a little practice the dial is easy to operate. It is much better than the G5 on which I am forever accidentally hitting the WB button by mistake.

Design detail  It is often said that the devil is in the details and that is true of camera design. Previous Lumix scroll wheels were deeply recessed into the body and  had rounded serrations. Those on the GH3 protrude  more prominently from the body and have sharper serrations. The combination of correct position and improved detail design makes them very much easier to use than anything I have previously used from M43 or, indeed any other camera system.

Pressing the Disp button. This is  easy enough with a little practice. However this button has to be pressed to reset  active AF area to the center position. This is not a bad arrangement but a JOG lever  between the AFL and Motion Picture buttons would be faster and smoother with less disruption to grip on the camera.

Buttons Most of these are well located and designed, with one partial exception, see below. Most are user configurable however I would like to see all of them capable of user choice as to function. The Playback, Motion Picture, WB, ISO and EC buttons could all have user selectable function. It is just a firmware issue. Most of the buttons are well sized and shaped although I think most could be just a fraction larger (in diameter, they are 6mm and I think could go up to 7mm) and more prominent (they could I think, usefully project about 0.5mm more from the camera body surface).  The Disp button has to be recessed so it is not accidentally activated, which is fine, but it too, could be just a little larger.  The exception is the top trio of WB, ISO and EC. These are in a row 23mm behind the center of the shutter button. Reaching them with the index finger without disrupting grip with the right hand is possible but only just and it's a bit of a stretch. These buttons could be 2-3 mm closer to the front scroll wheel and angled across the camera more to better follow the line of the right index finger. They could also sit up slightly higher with the center one being more prominent than the others and having a different shape to make it easier to locate by feel without looking.

All these picky little details about buttons add up to make the total user experience and are important.

Operations  All the actions required to take control of the camera's function are easily and quickly carried out. The camera does not get in the way of the image capture process but works with  the user in getting on with the job.

I would just say that if the Lumix guys (they do all seem to be guys) want to make the GH line the best cameras in the world they need to fit the next model with a JOG lever, located just between the existing AE Lock and Motion picture buttons (which would have to be relocated of course). If this were implemented optimally they could create a category killer camera design.

Summary The GH3 represents a big step up in ergonomic capability for the M43 system. Panasonic now has a camera and system which make a very good case for DSLR users to change camps.

 

 

 

Lumix GH3 Review Part 6 Sport/Action

LUMIX GH3 REVIEW PART 6  SPORT AND ACTION

It does a better job than many reviewers realise

Author AndrewS  April 2013

Don't try this at home. GH3, 35-100mm lens.  This type of shot would be difficult for any AF system. The subject is backlit, the background is brighter than the subject which is only about 15 meters from the camera. The horse is galloping. The camera could keep the subject in focus at Burst Rate M up to about this point in the arena but as they horses got closer they became progressively less sharp.

Introduction    Mirrorless ILC's [MILC] use contrast detect autofocus [CDAF] taking data directly from the imaging sensor. DSLR type cameras use phase detect autofocus [PDAF] operating from a separate AF module located beneath the mirror box, or in the case of Sony SLT cameras up near the viewfinder. In the early days CDAF systems were slower than PDAF types, but the latest versions are very fast indeed with single shot AF.  Until recently however mirrorless cameras have had  difficulty achieving follow focus on subjects moving towards or away from the camera with AF continuous and  Burst/Continuous drive at several frames per second.

GH3 with 35-100mm lens. Hang Gliders are easy subjects to photograph as they glide gently across the cliff top. In AFC  the GH3 will get almost 100% of frames sharply in focus if I frame accurately.

MILC focus systems   Manufacturers have used various strategies to improve focus speed  for MILC's. Most  have designed completely new style focussing mechanisms in MILC lenses utilising direct, low friction electro magnetic drive of the focussing lens group. This allows the lens focus to be racked back and forth at a much higher speed than was the case with previous technologies.   Another strategy, used by Canon, Nikon, Fuji and Sony, has been to allocate some 10,000 or so pixels on the imaging sensor to PDAF. The idea is to use the PDAF function to bring the lens quickly to near the correct focus point then locate the exact point with CDAF on the same sensor. From reports, this technology appears to have been implemented successfully by Nikon with the 1 Series, with the other makers to a greater or lesser extent playing catch up at the time of writing.

The conventional wisdom has been that CDAF could never match PDAF for sport/action use. However the Lumix  and Olympus M43 cameras have stuck with CDAF and are in fact making significant progress with follow focus capability.

GH3 with 35-100mm lens. This subject was handled easily by the GH3. This is one of a burst of 13 frames, all but the last few with the cars very close to the camera, were sharply in focus.

Note on "AF Tracking" often referred to incorrectly in user forums as "Focus Tracking"

Readers please note: There is much confusion about this in user forums.  There is no option called "Focus Tracking" in the lumix M43 Menu list.

AF  TRACKING  IS NOT THE SAME AS FOLLOW FOCUS

AF Tracking is a specific AF Mode in the GH3 and other  M43 cameras. In the GH3 it is selected via the [Fn3/AF Mode] button. The other AF Modes are Face Detection, 23 Area, 1-Area and Pinpoint.  It refers to a technology by which you ask the AF system to remember a specific subject element in the frame, such as a person's face,  your pet dog, or whatever, and continue to maintain focus on that subject element when it moves laterally within the frame. If you are really lucky your dog might stay in focus as it moves towards or away from the camera as well.

Follow Focus  This is a term which I use. It refers to the process by which the camera's AF system can sustain focus on a subject moving towards or away from the camera, using AF Continuous and Burst/Continuous Drive Mode. In this case it is the operator's duty to keep the active AF frame on the chosen subject to ensure the AF system is following the desired subject.

This article is about FOLLOW FOCUS   

I do not use focus tracking as it relinquishes to the camera an essential aspect of control over the focussing process which I want to keep myself. That is: On which part of the frame do I want the AF system to focus ?  I would be quite happy if the Lumix product team quietly dropped  "AF Tracking" from the list of AF Modes.

Readers please note:     The term "Follow Focus" does not appear anywhere in the Lumix list of focussing options.

It is the term I  use in connection with the process of autofocus on subjects moving towards and/or away from the camera. I always use and recommend setting [1-Area] AF Mode for this purpose.

I suspect that many of the adverse reports about this camera's AFC performance may have been due to the reviewer having set AF Mode to [AF Tracking] in the mistaken belief that this was appropriate.

Successful follow focus depends on optimal setup, preparation, technique and practice.

GH3, 35-100mmm lens. Large, steadily moving subjects in bright sunny conditions are managed easily by the GH3. Over several sequences totalling 50 frames, one was unsharp. 

Setup

Rec Menu

Page 1,

* Photo Style--Standard (only applies to JPG)

* Aspect Ratio--Any, I usually use 4:3 which provides the most opportunity for post capture cropping which is almost always required.

* Quality--Any. I use RAW. The GH3 has a fast procesor and big buffer which makes RAW capture very possible. Previous M43 cameras with slower processors and a smaller buffer required JPG capture for a sustained burst.

* Metering--Multiple.

Page 2,

* Burst Rate-- M or L.  M is the fastest rate which provides Image Preview [Live View]  on every frame.  The camera will focus on each frame at Burst Rate H but preview on each frame is  lost. Burst rate L obviously gives less frames per second but in many situations is quite adequate. The advantage of Burst Rate L is that the ratio of  Live View Time to Blackout Time is higher which makes the subject easier to follow in the EVF.

* i-Dynamic and i-Resolution--Off. You want to relieve the camera of any unnecessary data processing which would slow down frame rate performance.

Page 3,

* E-Shutter.    Burst Mode and AFC work with E-Shutter on however I usually leave it off because of the "rolling shutter" effect which can cause distortion with moving subjects or a moving camera and you will generally have both with sport/action.

Page 5,

* Shading Comp--Off

* Color Space--Adobe RGB

* Stabiliser--On--Standard

* If you are shooting JPG you can select Ex.Tele Conv or Digital Zoom here. Ex. Tele Conv works best as it allows full control of the position and size of the active AF area. Note that Ex.Tele Conv only works if Image Size is set to M (Medium, 8Mpx) which gives 1.4x, or S (Small, 4Mpx) which gives 2x.

Page 6,

* Face Recognition--Off.

GH3, 35-100mm lens. Same situation as the top photo.  Both frames are cropped.  I got about 50% of these sharply in focus which I consider a very good result in the circumstances. 

Custom Menu

Page 1,

* AF/AE Lock--AF-On. This allows the operator to start AFC with the back button if desired.

* Shutter AF--On

* Half Press Release--Off

Page 2,

* Quick AF--Off

* Eye Sensor AF--Off

Page 3,

* Direct Focus Area--On

* Focus Release priority--Focus.

Page 4,

* Histogram--Off

* Expo Meter--Off

Page 5,

* LVF and Monitor Style--Set to the style which places main camera data in a black strip beneath the preview image. You do not want anything cluttering up the preview image and you do need to monitor the shutter speed in particular without the distraction of having the data readouts overlaid on the preview image.

Page 6,

* Auto Review--Off.

Page 7,

* Eye Sensor--Auto. Some people prefer to have direct control of the EVF and prefer manual switching using the LVF/Fn5 switch.

* Touch Settings--Off.

GH3, 35-100mm lens. Pilot and photographer doing it easy.

Disp Button  Cycle this until the preview image is clear of all camera data. You need to have clear view of the lens aperture, shutter speed and ISO in the data strip beneath the preview image. The only items overlaid on the preview image are a minimal two line grid, if desired and the active AF area square.

Drive Mode Dial--Set to Burst.

Main Mode Dial-- Set to P or S. Depending on the lens in use and the subject a shutter speed of 1/500sec or faster will usually be required.   Another possibility is to make a Custom Mode setting after all the camera settings for Sport/Action are in place.

Focus Mode lever--Set to AFC.

Auto Focus Mode (AFMode/Fn3Button)--Set to [1-Area] Not AF tracking

ISO-- Usually set to Auto, however if you have set P Mode there may be situations where Auto Iso does not give a fast enough shutter speed in which case you will need to set a high ISO manually or switch to Shutter Priority Mode or both.

White Balance--Auto

Exposure Compensation--Usually nil. However there may be situations such as ice or snow when exposure compensation is required.

Preparation 

This is a camera user review not a camera use tutorial, however readers are advised that the follow focus performance of the GH3 or any other camera is highly dependent on user preparation and skill. Aspects of preparation include:

Lens Selection  Some lenses, particularly older ones operate more slowly than newer models. By this I mean they deliver a slower frame rate for any given camera settings. Presumably this relates to slower AF and aperture diaphragm operation. The Lumix 100-300mm OIS is unfortunately about the slowest I have tested which is a pity as it would otherwise be a first pick for sport/action. It is quite suitable for subjects which move fairly slowly and steadily in good light, such as board surfers. The Lumix 35-100mm f2.8 is faster but obviously suitable for a different subject profile due to the wider angle of view. The Lumix 45-150mm runs decently fast.

Shutter Speed/Aperture/ISO   When preparing to make action photos run some preliminary frames, keeping a close eye on your shutter speed and aperture. Make sure the ISO is high enough to give adequate shutter speed. The keeper rate will increase if you use an f2.8 lens at f5.6. So the camera focusses at f2.8 and captures at f5.6 for a bit more depth of focus.

Check the Light and the Background  All autofocus systems of any description look for areas of the frame with high brightness and/or contrast. Try to take a camera position to locate the light source behind or on one side of the camera and try to avoid bright/cluttered backgrounds. As you might expect AFC works best in bright light with subjects having a high brightness range ("contrast").

Technique

Zoom in to frame the subject but not too tight. Once the action starts you need to leave plenty of room to cope with the inevitable variations in framing accuracy. View through the EVF. You need to hold the camera as steady as possible and exclude non subject distractions.

Adjust the size of the AF box so it is no larger than the subject. You can shift position of the AF box also but I usually leave it in the center.

Don't zoom during capture bursts. I have tried this but it appears to throw the camera off target.

Start AFC with either back button press or half press shutter button and hold this for half a second or so for the AF system to acquire target. Then start capture by fully depressing the shutter button and hold it down for the duration of the burst.

In many situations Burst Rate L will be perfectly adequate and is easier to use than M rate as there is a greater proportion of viewing time to blackout time.

Performance-- Speed

The GH3 with Lumix 35-100mm lens, RAW capture, AFC, Burst Mode M, giving Live View and AF on each frame, using a Sandisk 95 MB/sec card, will capture 28 frames in 6 seconds [4.6 fps] before the frame rate slows suddenly. If capture is stopped at this point, the buffer clears in 7 seconds.

With the same settings and  Burst Rate L  the camera will continue to shoot RAW capture at 2.8 frames/sec for 50+ frames without slowing. If capture is stopped at 50 frames the buffer clears in 8 seconds.

This camera has a much faster/ higher imaging throughput capacity than previous M43 cameras and has more capacity than most cameras of any description.

Performance--Accuracy

The percentage of frames sharply in focus  is dependent on circumstance and operator skill.

Here are some examples :

Subject	Lens	% Sharply in Focus	% Just unsharp	%Blurred	Comment
Cars accelerating 15-40 kph	35-100mm @100mm  f2.8	75	22	3	*1
Cars accelerating 15-40 kph	35-100mm @ 100mm f5.6	78	20	2.5	*1
Cars at 60 kph	35-100mm @100mm	90	8	1	*2
Cars at 60 kph	100-300mm @250mm	52	34	14	*3
Board surfers	100-300 @300mm	68	28	4	*4

Comments

*1. Closing down the aperure from f2.8 to f5.6 gave a slightly higher rate of frames sharply in focus.

2.  All frames had to be cropped after capture as each car was not large in the frame.

3.  This test was run from the same camera position as the one above. The 100-300mm lens had a more difficult task as all the cars were larger in the frame so the change in focus position from one frame to the next was greater.

4. On a bright sunny day most surfing frames will be sharply in focus.

General Comments:

Most of the out of focus frames are those at the end of a burst when the car or other subject has come very close to the camera such that the change in focus from one frame to the next is beyond the camera's capability.

See the photo captions for further comment.

Conclusion  The Lumix GH3 is a moderately competent sport/action camera. I would place it approximately at the level of upper entry or mid range enthusiast DSLR for follow focus capability.  There are many types of subject in motion which it can manage quite easily with a high percentage of frames sharply in focus.

 

 

 

 

Lumix GH3 Review Part 5 Field of View

LUMIX GH3 REVIEW PART 5  FIELD OF VIEW

GH3  has less than GH2 and G5

Author AndrewS  April 2013

Introduction  Sometimes, in the course of testing photographic equipment,  one encounters an unexpected observation. While testing the Lumix 35-100mm f2.8 lens, using the Lumix G5, GH2 and GH3 cameras, I noticed that test chart pix with the GH2 and G5 included a larger area of the chart than those taken with the GH3.

The test  I use a simple kind of  test chart which is useful for comparing some aspects of the image quality of one camera or lens with another, but does not give absolute readings for technical matters such as resolution. I run the test chart pix in 4:3 image aspect ratio.  I found that with the same lens at the same focal length on the same tripod at the same distance from the chart, the horizontal field of view [HFOV] given by the GH2 and G5 was 2.5% more than that given by the GH3. I re ran the test with different lenses at different focal lengths but always came up with the same result. I used zoom lenses at the end of the zoom range to ensure there was no change in focal length from one test to the next. Unfortunately I did not have an Olympus OMD available for comparison testing.

Same lens, focal length and distance of focal plane from the test chart. The G5 and GH2 include 2.5% more horizontal distance as measured on the chart than the GH3.  In this case I used the 35-100mm lens at 35mm.  Actual HFOV  measurements were GH3 1026mm, G5 1053mm, GH2 1050mm. Viewfinder and Monitor view appeared to be 100% of the final output in each case

What does it mean ? 

1. For any lens at any given focal length and focussed distance the GH3 gives a slightly smaller HFOV than the GH2 and G5.

2. The actual imaging area of the GH3 sensor has to be smaller than that of the GH2 and G5.  Note that we know the total size of the GH2 sensor, also apparently used in the G5, is larger than most other M43 sensors because it was developed to be used with the multi aspect ratio facility of the GH2. I ran all the tests at 4:3 aspect ratio which I had expected would give the same HFOV with any M43 camera. Apparently not.

Published Data  The following tables have been compiled from various data sources, mostly the manufacturer or elsewhere as noted.

Sensor dimensions in millimeters and megapixels

Model	Nominal sensor dimensions, mm	Stated total M pixels	Stated Camera effective M pixels	Image size in pixels @ 4:3 AR
GH3	17.3x13	17.2	16.05	4608x3456
G5	17.3x13	18.31	16.05	4608x3456
GH2	17.3x13	18.31	16.05	4608x3456
GX1	17.3x13	16.68	16.0	4592x3448
EM5	17.3x13	16.9	16.1	4608x3456

 Notes: 

* All the sensors are given as the same nominal physical size of 17.3x13mm which is presumably not literally the case. 

* The GH2 and G5 appear to be using the same sensor.

* The numbers don't add up. 4608x3456 = 15925248, not 16.05 or 16.1.

* Camera data gives the pixel dimensions for 4:3 AR as 4608x3456 for the GH2, GH3, G5 and EM5.

* DXO Mark gives a slightly different set of numbers. [dxomark.com]

Model	Pixel Pitch	Camera effective pixels	Resolution as pixels
EM5	3.73	16.11	4640x3472
G5	3.74	16.05	4624x3472
GH3	3.74	16.05	4624x3472

What can one make of all this ? Probably that the technology is beyond my limited grasp.

Logically it seems to me that the pixel pitch of the GH3 should be slightly less than that of the G5 but they are given by DXO as the same.

My observations remain however, namely that the GH3  gives a bit less HFOV with any lens than the GH2 or G5.