Focus Lock is a very simple technique and one of the first things to learn. If used correctly it enables the photographer to take sharp pictures every time and to control which part of the picture is in focus.
Imagine You are in Egypt - visiting the Pyramids. You want to take a picture of your best friend with the Pyramids in the background. You also want to make sure he is sharp but not blocking the view. Point your camera at your pal and gently press the shutter button. Wait till you see the focus lock symbol (a red dot or green rectangle or square ). You might hear a beep as well. This tells you that the focus is locked and you can now take the picture. Oh no !! Henry is sharp but because he's in the middle of the picture - he's blocking the view and you can only just see the Pyramids. Try Again This time, do the same thing until you see the Focus Lock symbol and then KEEP your finger on the button and re-frame the picture. The camera will hold the focus point that you selected as you move the camera to put Henry to the side of the frame and press harder to take the picture - with the Pyramids - and loads of camels and some of those Egyptian sailing boats gliding by.
The Cupcake Challenge 1 Front focus 2 Back Focus 3 Repeat 4 Eat