So, I'm sure you have heard the famous quote from American photographer and environmentalist, Ansel Adams, " You don't take a photograph, you make it". These words couldn't be truer! Many people rely on chance or on the "photo Gods" to capture a great moment. This means carrying a camera 24/7, kinda being on stand-by and hoping for an awesome moment to occur so that hopefully they can snap the shutter and.. Boom, you just got yourself a pretty great shot! If you follow the law of chance, you can continue to do this and perhaps 1 out of every 1,000 frames you take might end up being a worthy image. The problem here is, you're at the mercy of luck and not yourself.
That is why the most famous photographs are not the result of luck, instead they were carefully planned out. Much thought goes into MAKING a great photo; timing it to the exact minute according to the positioning of the sun, the lighting needs to be just right. Photography is, of course, all about light. The photographer will have a pre-visualized image in their head, that is what they are aiming for. The awesomeness of a DSLR camera is, YOU are in control, YOU tell the camera what to do, YOU set the mode and make it happen.
When I shoot, either in studio or outdoor, I have an image in my head of the final outcome. I determine the possibilities according to my lighting situation. Is it a sunny day, are there clouds diffusing the light, does my location have trees to give shade? I know how I will want to edit the image, composition, cropping, overall mood and style. Once I am in place with my subject ready, I manipulate several exposure settings in my camera, it's literally a balancing act: