One of the questions I often get from people who have just bought a DSLR is, "What should I learn first?". There are a lot of things to learn when it comes to photography, but what I always suggest is to understand shutter speed, aperture and ISO. Setting these three values determines how much light comes into your camera. The correct amount of light will give you the proper exposure you're looking for.
Now, you can set your DSLR to fully automatic mode, fire off some shots and get a proper exposure most of the time. But, what happens when you look at the screen on the back of your camera and see this:
A great shot if you're trying to capture a nice shot of empty stands, but not so much if you actually want to see the face of #50.
I'll explain why the camera set this exposure in a future post. For now, it's an example of how fully automatic mode can fail you. Setting your camera to aperture priority or shutter/time priority would have given you the same results.
This is why I think this is the first thing you should learn. You have to know what to do to fix a shot like this. You can fire shot after shot in automatic mode and get the same result. Putting your camera into manual mode and adjusting your shutter speed/aperture/ISO values will allow you to expose this shot for the player's face (there's another way, but let's totally ignore that, since I'm trying to make a point here).
So, let's start with the easiest one to understand...
When I bought my first DSLR, the only thing I knew about camera settings is shutter speed. The faster the shutter speed, the better you can freeze the action.
No idea how fast or slow the shutter speed needed to be... heck, I didn't even know how to change the shutter speed.
The slower your shutter speed, the more light is let in to your camera. If your subject is stationary, you can set your shutter speed for multiple seconds, as long as you keep your camera steady. HOWEVER, if it's moving, then you'll have to figure out how fast your shutter speed needs to be to eliminate/lessen motion blur. I'll discuss some settings I go with for different situations in future posts.
I heard of aperture when I started, but all I knew was that it was some fancy schmancy word photographers threw around to make themselves sound smart. The aperture value is the size of the opening inside the lens that lets light into the camera. The lower the number, the larger the opening (for example, f/2.8 is larger than f/4) and the more light comes in. HOWEVER, the lower the number, the less area in front and behind your subject is in focus.
In the beginning, I went searching to find out what ISO stood for and quite honestly, I totally don't remember... and it doesn't matter anyway. The higher the ISO number, the more light your camera's sensor collects. HOWEVER, the higher the number, the more grain/noise appears in your image.
OK GENIUS, NOW WHAT?
Now that you understand the Holy Trinity of photography (or, now that I've totally confused you), take a shot with any values you want. Then, look at the result. Too bright? You can either speed up your shutter, make your aperture smaller, or lower your ISO. Too dark? Do the opposite. Take shots with your adjusted settings until you get a properly exposed shot.
You can now change one value up one click (settings are usually changed by rotating a wheel on your camera and one click changes the setting to the next value higher or lower), and another value down one click and the result is the same exact exposure. For example, if your settings are 1/250, f/4, ISO 400, you can make the shutter speed 1/320 (faster, less light), the aperture f/3.2 (larger, more light), keep your ISO at 400 and you'll get the same exposure.
Why would you need to change settings to end up with the same exposure? Well, that's what I'll talk about in my next post... hey, I need to space these things out, otherwise, I'll run out of things to blog about by the end of the month.