find what you're looking for

Saturday, February 11, 2012

dSLR basics II

Before we go much further, I want to discuss the technical aspects of the camera. If you look at your screen, you'll see something similar to this:

This is actually exactly what my screen looks like, yours may look a little different. All the information is basically the same.

For our purposes today, please change to manual. It's this setting:

Your aperture determines how much light is let into the camera while the shutter's open. A smaller aperture (or F stop) lets in more light than a larger aperture. Also, a smaller aperture means that anything besides the subject you're focused on will be fuzzy. Like this:

A larger aperture will allow you to focus of more stuff. It's great for landscapes or for pictures of more than one person.

You can change your aperture by holding down this button:
while turning this knob:

 This also determines how much light you let in. A faster shutter speed means that the camera will take a picture really fast, not allowing much light in. It's great for action shots. A slower shutter speed just means the shutter is open longer. This is expressed in fractions of seconds. In the picture above, the shutter will be open for 1/4000th of a second. If you see a number with " behind it, that means whole seconds. So 3" is 3 seconds. If you use a shutter speed of 1/30 or longer, grab a tripod. At those speeds you risk a blurry picture if you hold the camera. This is changed by moving this is changed by moving a button:

Shutter speed and aperture together create an exposure. The chart that you see here is to let you know if you're under or overexposing your pictures. An underexposed picture means dark, even black pictures. This is on the negative end of the chart. An overexposed picture means "blown out", or almost white, pictures. This is on the positive end of the chart. You want the little dot to line up right in the middle. Most of the time, if I can, I get a picture that's lined up to the middle dot, then 2 more: one at the "-1" and one at the "+1" end. You have to remember the camera is a machine, not a magical device. Sometimes letting it do its thing is okay, other times you need to take control of the reins. The exposure can be changed by changing either the shutter speed or the aperture. If you want a certain aperture, set it first then change the shutter speed to get the right exposure. If you want a certain shutter speed, set it, then change the aperture to the right exposure.
Back in the day, before digital photography, you could buy different "speeds" of film. This referred to the ISO or sensitivity of the film. In digital photography, this translates to "noise". The higher your ISO the more noise you will get. This is what this translates to:
Source. The one on the left is 100 ISO, the one on the right is 3200. 
For the most part, I personally stick somewhere between 100-400. There's no need for me to go above that, but that doesn't mean you need to stick to that range. Experiment and see what happens.

 If you need to take rapid fire or just one at a time, it can be changed by pressing this button and scrolling to a different selection:

White balance removes any unrealistic color casts in pictures. For instance, if you take a picture under florescent lights, but don't change the white balance you could end up with this:

See how yellow her hand looks. If you change the white balance though to compensate for that yellow light, it would look more normal. You change change your white balance by pressing this button:

That's it for today kids. We'll go over some more stuff next week. Have a great weekend!

No comments:

Post a Comment