Understanding Exposure and The Exposure Triangle

Exposure

Exposure is the amount of light that is recorded on your image sensor or film. There are three things that affect your exposure when you're taking an image - your aperture, shutter speed and ISO. These three things all affect the amount of light that your sensor capture, but they also have secondary effects.

Aperture controls depth of field.
Shutter speed controls motion blur.
ISO controls sensor sensitivity and noise in images.

Balancing these three things is the key to making good images.


Back to Digital Photography 101 Index

What is ISO in Photography?

ISO is your sensors sensitivity to light. Low ISO values (e.g. ISO 200) make the sensor less sensitive to light, which means that you would need more light to expose an image than you would need if you use a higher ISO value (e.g. ISO 1600).

Back in the days of film, you could only use one ISO at a time and that was the ISO of the film that you were using. With digital cameras, we have the ability to change out ISO on the go depending on the lighting conditions that we are in.

Low ISO (ISO 100) - Accurate colors and free of noise

ISO also affects the amount of noise that you have in your image. Digital noise are the random specs of colored pixels that you see in some images. The higher your ISO is, the more noise you will get in your images, which is why it is not ideal to raise your ISO more than you have to. Using higher ISO values will also skew how your colors look, making them look a lot duller than what is actually there.

High ISO (ISO 3200) - Noise is introduced and colors are not acurate 

When given a lot of light, you should use the lowest native ISO that you can. Increase your ISO when your shutter speed and aperture are at the point where you do not what to change them anymore. The ISO is usually that last thing that you'll change out of the three things that affect your exposure.

Back to Digital Photography 101 Index

What is Shutter Speed in Photography?

Fast Shutter Speed (1/500th of a Second) - Action is Frozen

Shutter speed is the amount of time in which your exposure takes place for. The longer your shutter speed is, the more light hits the sensor. The faster your shutter speed it, the less light hits your sensor.

Shutter speed also affects motion blur in your shots. To freeze action, you'll want a fast shutter speed. Using a fast shutter speed will ensure that your subject will be tack sharp when you take your photo. Using a fast shutter speed will also ensure that any camera shake is not recorded because of how quick the exposure is.

Slow Shutter Speed (25 seconds) - Car Light Trails

Slow shutter speeds will show motion blur. While most people will want to get tack sharp images with their subjects frozen, there are times when slow shutter speeds can be used to create successful images. When you want to show movement in a shot, you might want to slow down your shutter speed a little so that you can see the motion of your subject. Other popular techniques using slow shutter speeds include capturing light trails and making water look silky smooth. When you slow down your shutter speed, camera shake will be introduced. To avoid this, a tripod is recommended for those longer exposures.

Slow Shutter Speed (1.3 seconds) - Shows Movement

Of course, you'll also have to take into account your aperture and ISO when taking a photograph.

Back to Digital Photography 101 Index

What is Aperture in Photography?

Aperture is the physical opening of the lens

Aperture is defined as the physical opening of your lens. A large aperture lets more light into your camera than a smaller aperture would. The aperture is measured by f-stops. Larger f-stop numbers (f/16) signify a smaller physical aperture. Smaller f-stop numbers (f/2) signify larger physical aperture. F-stops and aperture size can be a little bit confusing at first, but you'll get the hang of it pretty quickly.

Large Aperture / Small f-stop (f/1.8) - Shallow Depth of Field

Asides from controlling the amount of light that enters the camera, your aperture also helps to control your depth of field. Depth of field is how much of your image is in acceptable focus. Larger physical apertures, or smaller f-stop values, gives you smaller/shallower depth of field. This means that less of your image beyond your focus area will be in focus. A smaller physical aperture, or larger f-stop value, will give you a larger/deeper depth of field. This means that a large portion beyond your focus area will be in acceptable focus. 

Small Aperture / Large f-stop (f/7.1) - Deep Depth of Field

Of course, you'll also have to take into account your shutter speed and ISO when taking a photograph.

NEXT - What is Shutter Speed in Photography?

Back to Digital Photography 101 Index

Wacom Intuos Pen and Touch (2013) Unboxing and First Impressions

Wacom has made a lot of changes in the naming of their products and this includes the introduction of the new Wacom Intuos line of tablets, replacing the former Wacom Bamboo Tablets (the Bamboo name has now been designated to other products). This new lineup of pen tablets includes two Intuos Pen and Touch models (a small and a medium size), a Pen only model that comes in the small size and an Intuos Manga model (Pen and Touch bundled with different software). The new Wacom Intuos line is very similar to the outgoing Bamboo models, but Wacom has made a few changes in build quality and in features that make these new tablets appealing to those that are getting their first tablets.

UPDATE: The full review is available here.

The New Home of CamCrunch

Welcome to the new home of CamCrunch! After numerous problems with Wordpress, I've decided to come back to Blogger. I'll be developing the website over here for now. If the site ever grows to the point where Wordpress is needed again, I'll move it back over to that platform. For now, I think Blogger will be mere than enough to keep this site moving forward.

Shoot-Through vs Reflective Umbrella

One of the first pieces of kit that you will want to invest in when you start to do off-camera flash work is a nice umbrella. The umbrella is a type of modifier that can change the way the light from your flash looks like when it hits your subject. The reason why the umbrella is one of the first modifiers that people buy when they are starting off is that umbrellas are versatile, fairly compact and easy to use. There are two types of umbrellas - shoot-through umbrellas and reflective umbrellas. This short guide will run you through the two basic types of umbrellas that you will run into, what the benefits are of using one over the other and my personal recommendation as to which type of umbrella you should get as your first umbrella.