Why I enter "Live View" on my Nikon D5100, the mirror is locked up and I see a live view of whatever the CCD is seeing on the articulated screen just like a mirrorless system.
But when I go to take a picture, suddenly the screen shuts off, and I hear four separate noises. It sounds like the mirror is being lowered, then the shutter which has a kind of double "chaching" sound, and then another mirror which sounds like the mirror being lifted again.
But this makes no sense to me! The mirror has to be lifted to enter live view, as well as to take a picture. The shutter already has to be open for the sensor to capture light to be displayed on the screen. The image is already hitting the CCD as seems evident by the fact that it is being displayed on the screen. So why do I need to hear any noises at all? It's needlessly loud and delays the shot a bit. It seems like it should just record the shot. If I record a video it just does it without any extra delays or noise.
I looked in the manual and it says the screen will go off while the shot is being taken, but there wasn't any mention of this other nonsense. Why is this happening and how do I make it stop?