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| Mechanical shutter 1/80sec |
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| E-Shutter 1/80sec |
All Micro Four thirds cameras to date have a mechanical shutter. All of those which I have tested to date can produce unsharpness with or without double imaging with some lenses at some shutter speeds.
In order to prevent the occurrence of this nasty little problem recent Panasonic cameras have an Electronic shutter and recent Olympus cameras have an "Antishock 0" setting, which has been reported to utilise an electronic first curtain.
On my testing Panasonic E-Shutter completely eliminates blurring due to shutter shock. I have not tested Olympus Antishock 0 but it is also reported to be effective.
I have no idea why Panasonic does not offer electronic first curtain shutter operation. Several other manufacturers do and it is reported to eliminate the shutter shock problem with no adverse effects as far as I am aware.
The benefits of Panasonic E-Shutter are the result of there being no mechanical parts thus allowing
* Silent operation, with or without beeps as set in the Custom Mode.
* No vibration and therefore no blurring due to shutter shock.
The disadvantages of E-Shutter are largely due to the fact that the process of scanning the sensor electronically takes 1/15 second. The GH3 E-shutter takes 1/10 second.
* Incompatible with electronic flash.
* ISO limited to 3200. (1600 in the GH3).
* Longest shutter speed available is 1 second. For vibration free exposures longer than 1 second set Shutter Delay page 4/7 in the Rec Menu.
* Subjects moving in relation to the camera may be distorted in shape.
* There have been reports that E-Shutter on the GH4 may provide only 10 bit capture. Panasonic M43 cameras have 12 bit capture with the mechanical shutter. The trade off for the faster scanning speed on the GH4 may be a lower bit rate.
The Panasonic GH4 has a faster mechanical shutter than the GH3 which allows a faster shutter speed to be used with flash (1/250 sec vs 1/160 sec) and a faster top speed (1/8000 vs 1/4000) which can be useful in bright light when a wide lens aperture is desired. I was wondering if it also causes more problems with shutter shock than the GH3 and other Panasonic M43 cameras.
So I ran my usual test procedure which is:
* Select camera body, lens, focal length for testing.
* Set up a suitable test target. I use classified adverts from a newspaper as this provides clear differentiation between sharp and unsharp frames and readily shows any double imaging if present.
* Mount the camera on a sturdy tripod. This is to eliminate camera movement as a source of any unsharpness.
* Use remote shutter release, wired or wireless, for the same reason.
* Switch OIS or IBIS off. This is recommended by the manufacturers for tripod use.
* Set Shutter Priority auto exposure and auto ISO.
* Focus with AF or MF. Run some preliminary tests to ensure your equipment is focussing accurately.
* Make a series of exposures from 1/4 sec to 1/500 sec. Use the mechanical shutter for the first run then the E-Shutter (or Olympus Antishock 0) for the second run.
* Look at the results at 100% on screen. Any unsharpness or double imaging will be clearly evident.
On this occasion I used the Panasonic 14-140mm lens set at 140 mm. I had previously determined that this lens at this focal length is affected by unsharpness due to shutter shock with the GH3 and G6 camera bodies.
* Select camera body, lens, focal length for testing.
* Set up a suitable test target. I use classified adverts from a newspaper as this provides clear differentiation between sharp and unsharp frames and readily shows any double imaging if present.
* Mount the camera on a sturdy tripod. This is to eliminate camera movement as a source of any unsharpness.
* Use remote shutter release, wired or wireless, for the same reason.
* Switch OIS or IBIS off. This is recommended by the manufacturers for tripod use.
* Set Shutter Priority auto exposure and auto ISO.
* Focus with AF or MF. Run some preliminary tests to ensure your equipment is focussing accurately.
* Make a series of exposures from 1/4 sec to 1/500 sec. Use the mechanical shutter for the first run then the E-Shutter (or Olympus Antishock 0) for the second run.
* Look at the results at 100% on screen. Any unsharpness or double imaging will be clearly evident.
On this occasion I used the Panasonic 14-140mm lens set at 140 mm. I had previously determined that this lens at this focal length is affected by unsharpness due to shutter shock with the GH3 and G6 camera bodies.
Results I got essentially the same results with the GH3 and GH4. With the mechanical shutter, speeds of 1/15 sec or lower were no problem. From 1/20s to 1/50s there was some blurring visible. From 1/60s to 1/200s there was blurring with double imaging. 1/250s and 1/320s were slightly soft. 1/400s and faster were sharp.
When using the E-Shutter all the frames were sharp.
Recommendations for use With the 14-140mm lens I always use the E-Shutter for general photography and have no problems at all.
If I want to use a shutter speed of 1/500 sec or faster which is usually for moving subjects, sport/action and the like, I set E-Shutter OFF which causes the camera to revert to the mechanical shutter.
If I need to use a shutter speed longer than 1 second, with the camera on a tripod, I set Shutter Delay to ON. If I am firing the shutter remotely a delay of 2 seconds is plenty. If I press the shutter button it can take longer for the camera to settle down so I use 4 seconds.
The only problem with these usage strategies is that you have to keep an eye on the shutter speed and remember when to switch the E-Shutter on or off.
Some in the camera commentariat have proclaimed the E-Shutter to be "useless" because of it's limitations. But I use it all the time with no problems at all. One just has to be aware of the limitations and work around them as described above.
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