Originally Posted by
Dave Humphries
For the Shutter of most Nikon DSLRs released in the last oooh, probably 10 years, they have had a "Quiet" shutter mode which when engaged seems to muffle the shutter and mirror slap noises, mostly by spacing them out from each other.
Test Case on my D7100: if the shutter speed is say 1/100s, but you keep your finger on the shutter release for one whole second (bear with me) ...
a) In normal "S" mode, you get the typical rapid "mirror up, first curtain, second curtain, mirror down, shutter re-cock" all in quick succession
b) In "Q" or "Quiet" mode, you get mirror up, followed by first and second curtains, but the mirror doesn't go down and shutter re-cock, until you let go of the release shutter. So it also gives you more control over when to make some of the noise, if you see what I mean. According to the manual, which I read after my test, it also disables any beeps ('AF success' I assume they mean).
I don't use it often, but it can be useful on occasion, although as you can tell, it has limitations.