Back when, I started off in photography, I was fortunate to take a lesson from a seasoned Pro. I saw his images and was basically blown away by them. I called him up and the next time he was in my area, I paid him to spend a couple hours with me, so i could ask him everything i could think of about taking professional shots.
It basically came down to really understanding exposure time. Most of us use the automatic feature on our cameras and just shoot away ---which is fine if you want to take snapshots and not dynamic wow images.
The situation is this--All cameras when left to automatic exposure want to shoot everything at neutral grey. For example-Take a shot of snow and notice that the snow is blue and not white??
So why is it not white-It was white when i looked at it----So what do you do to make it look white. You have to open up the lens say one and 1/2 to two stops to let more light in--(The camera has to be set on Manual---anyone that wants to take dynamic pictures and be in control of the camera instead of the camera being in control of you need to be able to choose the exposure time and lens opening,
Lets look at it another way-say you are shooting something and you want the blacks to really be black--if you shoot it in automatic--it will be neutral grey, not black like you wanted. So what do you do---close the camera stops down 1 to 2 stops and let less light in.
To try this out go into your backyard and take some shots-Forst shoot something automatic where you want the whites to be white---then open the lens up a stop and notice the difference.
It will take time and lots of trial and error as to to correct exposures--both the lens opening and the time to get it the way you want. The goal is to look at a scene and have it come out the way you want t to come out.
There are tons of books on this subject---some of the best are by John Shaw.
My website is at www.dhphotoart.com