Silent Shutter and Fastest Flash Sync Speed
Page 173: 1/15 sec in the E-M1 pdf manual
Found a Panasonic discussion - here is the link. http://m43photo.blogspot.com.au/2014/03/gm1-shutters.html
It would be similar to the E-M1 silent shutter.
Choose Silent when
a. I am doing Street Shooting discreetly, or for other times when a shutter sound is intrusive.
b. I want fastest high shutter speed 1/16,000 when I want brightest aperture for max background blur
I would chose mechanical when
I shoot electronic flash - the fastest sync speed for silent is 1/15 sec. In fact it appears like the only way to activate the flash with silent shutter is to activate Focus Bracketing. The minimum number of exposures you can set here is three, the shutter speed will be fixed at 1/13 sec. and the flash is fixed at Manual 1/4. (from Hans van Veluwen)
when I want an obvious sound to tell myself easily the shot is done or how many shots in a high speed burst.
to avoid risk of jello motion effect
allthough I don't normally use Full time AF, it is not available with silent.
Max ISO of Silent shutter is 3200. If I want higher than that I have to use Mechanical Shutter
If I want Focus Confirm Beep, for patient macro shots, Silent Shutter forces that to switch off.
Silent shutter has a slowest time of 1/8 sec. Mechanical Shutter has a slow limit of 60 secs
Olympus is typicallly using CMOS sensors = Rolling Shutter