None of what I shot that day has any real value, but what I shot that day did show that I had a way of seeing things that lent toward the capture of interesting images, and what I shot that day showed that I had a natural tendency toward good composition. But I didn't know squat about photography. With the camera set to auto I was pretty much at the mercy of the machine to set the exposure for me. Aperture, shutter speed, and ISO weren't no part of my working vocabulary. Yet an understanding of these variables, and how to use them, is critical to consistently creating great images, no matter how much a love the photographer has, or how much raw ability the photographer has in the art of seeing. Go to any photo forum and you'll find posts galore about the technical dooditties of photographic equipment. While it can be useful to know about all the techno-wizardry of modern cameras, this stuff is very much of secondary importance in a photographer's bag of knowledge. Taking great photos ain't about your pixel count.*
When it comes to the technical aspect of the craft, what is of primary importance is setting the proper exposure. What began my real education in photography (besides just going out and doing it) was reading Understanding Exposure, by Bryan Peterson. Illustrated with beautiful photographic examples, he writes simply and clearly about how to adjust your aperture, shutter speed, and ISO in order to create the exposure you choose so as to capture an image in the way you wish. If you set the camera to auto, you'll sometimes get an exposure you want, sometimes not.
It seems so simple. You have only three variables for creating the proper exposure. But they interplay with each other in ways that can be a little complicated at first, and takes time to understand, requiring the photographer to play with the variables in many different kinds of photographic situations in order to master them. Bryan's book gave me years of learning in a matter of 158 easy to read pages, loaded with great example images. If you don't know what exactly an f-stop is, but would like to, or even if you don't, but want to take your photography to a higher level, Understanding Exposure is a great place to begin. The fundamentals of any craft are necessary to learn for anyone who wishes to create consistently good results. This book is an excellent course on the fundamentals of photography.
After having read this book, I now almost always shoot in manual. Sometimes I select aperture priority, sometimes I shoot in shutter priority, but most of the time manual. It's about being in control of the exposure so I get an image according to what I want it to be, not according to what the camera thinks it should be.
*Understanding pixels can help you understand and hone your final image output, but does nothing for image quality if you don't know how to handle the camera. More isn't better. It's just bigger, and maybe you need it and maybe you don't.
Glossary
Aperture priority: camera setting where you choose the aperture, and the camera selects the shutter speed to get the exposure it thinks is accurate.
Manual: camera setting where you choose both the shutter speed and aperture, and the camera obeys.
Shutter priority: camera setting where you choose the shutter speed, and the camera selects the aperture to get the exposure it thinks is accurate.
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