There are a lot of tips out there for getting your photos as sharp as possible. “Tack sharp” is just a way of describing how sharp the focus of a particular photo is. Out of focus photos are the worst; they’re all blurry and fuzzy, and no one enjoys look at them. One idea is to use a faster shutter speed.
This is how long it takes your shutter to open and close. The idea is to have a shutter speed that takes as little time as possible to open and close. If you have a shutter speed of 1/50 second, and you’re still getting blurry pictures, try a shutter speed of 1/75 or 1/80 second. You’ll get a much clearer picture.