Only the basics have been presented here in this tutorial.
The main thing is that you should have enough information now to be able to take some control of your camera.
Take lots of photographs and after a little bit of practice setting ISO, aperture and shutter to obtain the results you want will become second nature.
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However there is still a lot more to learn and there will be more tutorials similar to this one.
Here are some references to help build your skills.
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(1) "Understanding exposure" by Bryan Peterson - ISBN 0-8174-3711-8 or ISBN 0-8174-3712-6 (Paperback)
......... I feel an excellent guide to the concepts of exposure. It is not camera dependant.
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(2) For Canon Digital Rebel (300D-350D & 400D ) users. The Digital Rebel Field guide by Charlotte K Lowrie.
... ISBN-13: 978-0-7645-8813-6 or ISBN-10: 0-7645-8813-3
..... A good extension of the camera manual.
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(3) And most important - The book that came with your camera!
Remember - Rule # 1 - Read the book! - the one that came with your camera.
Some exercises.
(1) Take a series of hand held photographs (at different focal lengths if you have a zoom lens) to see how slow of shutter speed you can use and still get a sharp photograph
(2) Take two photographs showing creative use of depth of field, at both extremes