If you like to study the way of taking pictures in Manual mode, maybe this eBook by Kimberly Gauthier might inspire you. Simple and straight to the point explanation from her will give you the straight answer. On her own word :
I write a photography blog for amateur photographers. I'm a self taught photographer and was surprised to find very few resources for people, like me, who were learning how to use their DSLR on their own. Today, I write a photography blog sharing everything that I've learned and I search for online camera deals, giveaways, and challenges for my readers. My first eBook, My Five Easy Steps to Shoot in Manual, is available for free on my photography blog and Facebook page.
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