Electronic shutter: advantages and disadvantages

For the impatient - Dave was on the right track - I am now pretty certain that the issue with the photo I posted previously was that focus was adjusted during the exposure...

Dave Lively wrote:

texinwien wrote:

rurikw wrote:

Could imagine problems with handheld architectural photography: vertical lines becoming slightly wobbly or skewed. Anybody noticed anything like that?

Yes, I do believe you're correct here.

Out of several thousand photos I took with my E-M5 II on a trip to Tuscany earlier this summer, most with the E-Shutter, I have noticed a very small number of degraded results that I think are explained by the phenomenon you suggested.

Were you using continuous autofocus?

I was using S-AF + MF. But thanks for asking, and thanks for suggesting that I perform some tests. I wasn't really convinced with my previous theory, and hadn't been too motivated to test it, since I'd only come across a small handful of examples of the phenomenon.

An alternate explanation would be that if you were using CAF the camera focused past infinity halfway through the exposure and then pulled back but not enough. A lot can happen in 1/25 of a second.

Although I wasn't using C-AF, I'm now almost certain your thinking (focus adjustment during exposure) is the culprit.

I have taken photos with motion blur using the ES and they do not look like that. Motion blur usually has a smeared appearance and the right half of your sample looks soft all over. When using the ES I typically see motion blur in bands that vary and the right half of the photo is soft in a very uniform way. It would be very hard to generate constant motion blur like that. At 12mm and 1/1000 it would be hard to generate motion blur at all but you could see some artifacts from the electronic shutter.

Try taking a picture with a 300mm lens with a high shutter speed, using the electronic shutter, with IS off and without a tripod. I have done this and what you typical get is straight vertical lines (if you are in landscape mode) stay sharp but become squiggly or curved.

I just tested with my 75-300mm attached to my E-M5 II as you suggested. While I was testing, I double checked my AF settings, and a lightbulb went off in my head when I saw the 'MF' appended to the 'S-AF' -- maybe I accidentally bumped the manual focus ring on the 12-40mm during the exposure.

So I threw in a few tests with the camera in Low Speed Drive + E-Shutter mode where I locked AF on my target before depressing the shutter button and turned the focus ring slightly back and forth (still on my 75-300mm) while firing off the burst.

The proof is in the pudding. None of my initial test shots (wherein I wasn't adjusting focus) look like my initial example - they all seem to be uniformly blurry or sharp. The story is different for the ones I took while adjusting the focus ring - some of them look rather similar to my original example, with one half much sharper than the other.

As I mentioned in my first post, I was in an awkward stance when I took the sample photo, and I'll bet I simply bumped the focus ring on the 12-40mm inadvertently during the exposure.

Again, thanks for pointing me in the right direction and suggesting some good tests.