MICRO 4/3 CAMERA PRACTICE
SHUTTER SHAKE SYNDROME [S.S.S.]
Author AndrewS May 2012
This week I have been running tests to compare the Panasonic 100-300 mm lens with the Olympus 75-300 mm, both on my Panasonic GH2 camera in a variety of situations and shooting conditions. Somewhere in the middle of several hundred test photos I discovered some which exhibited marked blurring with double image effect. So I had to embark on a tangential line of enquiry to figure out the cause of these highly unwelcome fuzzy frames.
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| Blurred frame with double imaging |
I ran tests on the Panasonic 45-200 mm and Olympus 40-150 mm lenses as well as the two longer zooms. My findings are:
1. S.S.S. Occured with the camera on a sturdy tripod, well grounded, shutter activated by wired remote or timer delay. Outdoor shots were made on a calm clear day with no wind. Indoor shots used a test chart and the same tripod. The tripod head was attached by the socket on the camera body.
2. The phenomenon occured with OIS (only relevant to the Panasonic lenses) switched ON or OFF. It also occurred with Olympus lenses (no OIS) on the Pansonic body (no IBIS) so it cannot be attributable to any form of IS. All four M43 lenses are good copies, working properly.
3. Image blurring appeared with all four M43 lenses in the shutter speed range 1/20 second to 1/200 second, with the worst examples around 1/100 second. Mysteriously, most but not all frames at the critical shutter speeds were affected. Most severely affected were the longer lenses at their longest focal length.
4. I tried holding on to the camera while it was on the tripod in an attempt to dampen vibrations. This did not improve matters at the higher end of the S.S.S. range (1/100-1/200 sec) and made things worse at the lower end of the range ( 1/20 - 1/60 sec).
5. I ran a series of test shots with the GH2 plus 100-300 mm lens @ 300 mm, on a monopod, OIS ON. Obviously slow shutter speeds gave blurry results. But at the upper end of the critical range for S.S.S, the pix were blurred up to about 1/200 sec, worst at 1/100 sec, coming good at 1/250 sec and faster.
These findings indicate that I cannot get reliably sharp shots between 1/30 sec and 1/200 sec with the Panasonic 100-300 mm or Olympus 75-300 mm lenses on the Panasonic GH2 body, by any means at all.
This is relevant for the work which I want to do with these lenses which is telephoto landscape and cityscape.
6. I ran the tripod mounted tests with a Samsung NX11 and NX 50-200 mm lens. This combination also showed some S.S.S. in the 1/60 - 1/200 sec shutter speed range. My notes describe the images in this range as "a bit soft". In other words the S.S.S. effect was present but not as noticeable as the GH2.
7. Next up was the Canon 60D with EF 70-200 mm f4 L IS lens. On the tripod without mirror lock up (MLU) images were extremely blurred at 1/4 and 1/8 sec due to mirror slap, but good at slower and faster speeds. In live view mode with the mirror up I saw no convincing evidence of S.S.S. One frame at 1/200 sec was soft but this could have been due to unreliable focussing which plagues this camera. This camera uses electronic exposure start in live view mode. The mechanical shutter is used only to end the exposure. I would therefore expect no problems with S.S.S and found none.
My hypothesis is that the the quadruple action shutter used on the GH2 (and other mirrorless cameras) is the cause of the problem. This has a close>open>close>openaction on each exposure. The initial close>opensequence produces vibrations which occur during the exposure and can easily be felt with a hand placed gently on the lens. If I am correct, an electronic first curtain shutter should eliminate the problem.
I wondered initially why OIS was unable to prevent the blurring then on reflection realised that OIS is designed to compensate for instability caused by manual handling which produces relatively large, slow movement cycles. But the shutter produces a short, sharp shock (another S.S.S. !) which passes through the body/lens mass before for OIS can respond.
So, while waiting for the next GH camera iteration, hopefully with a different shutter system, I will try to remember that I must avoid firing solutions (Aperture, ISO, Shutter Speed) which produce speeds in the S.S.S danger range.
Note: Last year I bought a Panasonic G3 and 45-175 mm OIS lens. This combination produced a very severe case of S.S.S. at almost all shutter speeds such that the lens was not serviceable so I returned it to the vendor. I believe there was probably a fault in the OIS module of that lens making it excessively sensitive to shutter vibration with the OIS switched ON or OFF. OIS appears to be working normally on the Panasonic 45-200 mm and 100-300 mm lenses tested for this report.
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