Introduction: The Three Ingredients for a Perfect Picture
Have you ever wanted to take on photography but not know how to take a good picture without auto mode? Well, in this instructable, you will learn to go outside the boundaries of auto mode, and learn to take a good picture on your own.
Step 1: The Shutter Speed
So what is the shutter speed? Well, in your camera, there is a little thing called the shutter. When you press down the button to take the picture, the shutter opens and closes. How fast this happens is the shutter speed.
So what happens when the shutter speed is low? Well a low shutter speed (like 1/2 of a second) means that more light will pass through, and also that your picture will be blurry with any movement. Why is this? A low shutter speed means that the shutter is slower opening and closing. Because of this, the picture can get more light but also have a better chance of blurring the picture.
A high shutter speed is different. The picture will be crisp and sharp, however the amount of light brought through is very small.
Now that you know something about the shutter speed, the examples above will help you better understand how this works out.
Step 2: The Aperture
Basically, the aperture is the hole in your camera lens that lets in light. Think about your eyes; the cornea is like the front part of the lens (the part that lets in external light and bends it and passes it to the iris). Then the iris can either expand or shrink, depending on the amount of light in a given circumstance, controlling the size of the pupil. The pupil is a hole that lets light pass further into the eye: this is what the aperture is. The larger the pupil (or aperture) the more light passes through. The smaller the pupil, the less light passes through.
The aperture in photography is known as the f/stop; with numbers such as f/8 or f/22 or f/1.8. The larger the number, the smaller the aperture; the smaller the number the larger the aperture. For an example, look at the first picture above.
One other thing to mention, which is very important, is that the aperture directly relates to depth of field. A depth of field is the area of the image that looks sharp. A high f/stop means that all background and foreground images will appear clear. A low f/stop will result in only the focused part of the image look clear, everything else will appear blurry. Look in the 2nd picture: the left horse has much less depth of field than the one on the right.
This is the simple basics of aperture.
Step 3: The ISO
The ISO stands for the International Standards Organization - the main governing body that standardizes sensitivity ratings for camera sensors. Your ISO adjusts the camera's sensitivity to light. First of all, you should know that a higher ISO usually means a "grainy" or "noisy image, like in the first picture above. If you want to lower the ISO, then you need more light. Usually, you would want to stick to the "base 10" of your camera whenever you can. What is that? Well, every camera has its own "base ten", which can vary (like 100 or 200); but this produces the lowest ISO with the highest quality image. That is why you should typically use your base ten.
Low ISO (like 100): Good quality image, but needs light
High ISO (like 3200): Bad quality image, but collects more light.
Usually, base ten numbers double in value (100, 200, 400, 800, 1600, 3200, etc.), making their sensitivity also double. For example, 400 ISO is twice more sensitive than 200 ISO, or four times more than 100 ISO. What does being four times more sensitive mean? It means that it needs four times less time to capture an image!
ISO speed example:
ISO 100: 1 second
ISO 200: 1/2 second
ISO 400: 1/4 second
ISO 800: 1/8 second
ISO 1600: 1/16 second
ISO 3200: 1/32 second
*Keep this in mind: a lower ISO is always better when there is plenty of light. However, you should increase the ISO whenever there is not enough light. But before you take the picture, make sure that it is ok to have a little grain or "noise" in your image.
This instructable showed you the basics of shutter speed, aperture, and ISO. Although there is much more to photography, this is what a picture is made of.