What is the best digital camera to buy?

Short Answer: There is no such thing as the "best digital camera to buy".

Disappointed with this answer? Don't be! If you change your question slightly, you'll have the information you really wanted to have in the first place. Reading this article now will let you always know how to figure out which camera is best for you, and can save you hundreds of dollars and much frustration!

First thing you need to know: this is not a digital camera buying guide :)

You've probably heard words like "megapixels" and "wide-angle lens" thrown around before but what do they really mean? More importantly, with all these different cheap camera models out there what's the catch? What makes one manufacturer's camera better than another? If you want to know the answer, keep reading!

This article's goal is to make you aware of what you're getting when you buy a digital camera so that you're not disappointed with the final product.

This is not meant to be a super technical article. My goal here is to keep things simple and short, not to write an encyclopedia entry. That being said, sometimes you do need to know a few technical things if you don't want to be ripped off in life (for example, would you buy a car with a 1 horse power engine? That's a pretty technical term that really makes no sense by itself but most people know buying a car like that is a pretty bad idea!)

Fortunately in my experience there are really only three technical things you need to know about when buying digital cameras: the digital camera sensor, the camera shutter and the camera lens.

The is the thing in the camera that "sees" the outside world. It tells the computer chip in the digital camera exactly what it's seeing so that the computer chip can save that information into a digital photograph file. Film cameras didn't have digital camera sensors -- they had film :) This is what makes digital cameras "digital".

What does it "see"? Light of different colors! Just like your eyeball is made up of rods and cones that can detect different colors, sensors are made up of things called 'pixels' that can see different colors. Think of a pixel like a bucket that collects colors instead of water. By the way, a million of these pixel bucket things is called a "megapixel".

Sensors are sensitive! You can tell sensors to be more or less sensitive to light. Why would you do this? Well, if it's dark and there isn't much light around then you would want your sensor to be more sensitive to light. During the day you don't want the sensor to be as sensitive as it is at night -- otherwise your pictures will be too bright since the pixels will collect too much light!

ISO rating. There is a standard way to tell the sensor how sensitive to be. This is the "International Standards Organisation 12232:2006 standard". Since that's not a very practical name, people just shortened it to "ISO". The standard basically says that higher "sensitivity rating numbers" mean the camera sensor is more sensitive to light. So, an "ISO 200 rating" is twice as sensitive as an "ISO 100 rating". That means your picture will be twice as bright at ISO 200 than when it is at ISO 100!

Sensors come in different shapes and sizes! As you can see in the diagram here, you can get big sensors and you can get small sensors. You can get wide sensors and you can get square ones. The shape of the sensor is called the "frame" or the "format" of the sensor. Also, the more pixels a sensor has, the more detail you get in your digital photographs.

Sensor noise. Lurking in the shadows of all of the above is the digital camera world's ultimate bad guy: Sensor Noise. (Can somebody draw me an evil villian?) When you make your sensor more sensitive, the laws of physics mean that your sensor starts seeing things other than light. You've probably seen this with cheap cameras (especially cellphone cameras), or in night photos taken without a flash: the photos have ugly spots all over them. Camera manufacturers try to get clever and take the noise out of photos (this is called "noise reduction"), but it rarely works very well so don't depend on that.

Keywords: whenever you see these words, you now know that people are talking about digital camera sensors: sensor size, frame, format, megapixels, ISO, ISO rating, sensitivity, noise, noise reduction.

So light gets sucked into these pixels buckets sitting on the camera sensor, and all the light sitting in these pixels makes up a digital photograph. But there's a problem here. It has to do with the nature of light.

Consider these two scenarios:

1. You look at the sun for a brief moment and then look away. Your eyeballs hurt a bit but you're probably going to be OK.
2. You look at the sun for ten minutes and then.... at some point your eyeballs melt.

What changed? You were looking at the same object but got different results depending on how long you looked.

Pieces of light move one at a time! The problem is that light isn't something that is "just there". What's happening is that the sun is constantly shooting out bits of light. These bits of light move across space and bounce off various things in their way until eventually they end up getting sucked into your eyeball where they hit your rod and cone sensors.

After a while, you have collected too much light! The longer you look at the sun, the more bits of light hit your sensors. But since light particles carry energy, that energy needs to go somewhere when it hits the rods and cones, and it basically turns into heat energy. Eventually there's just too much energy and your eyeball melts. This is just like when you use a magnifying glass to start fires or to cook ants: the fire takes a while to get going -- it doesn't all happen at once!

Eyelids for your camera. Just as you can close your eyes with your eyelids to shut out too much light from damaging your rod and cone sensors, digital cameras have shutters that can shut light out from reaching the sensor. The amount of time the camera shutter stays open to let light into the camera is called the shutter speed.

The world is pretty big. The camera sensor is much smaller than the world it's supposed to see. That means the light coming from the world needs to be squished into something that will fit onto the sensor. That's what camera lenses do.

Telescopic lenses. There are many different ways to squish light. Some lenses squish light so that you can see things that are very far away as if they were right in front of you (these are called "telescope" lenses because they act like telescopes).

Wide lenses. The opposite of a telescopic lens is a "wide angle" lens. This just means you can see a lot more of what's around you, rather than a lot of what's far away from you.

Zoom lenses. Most lenses you find on consumer digital cameras aren't fixed as either a telescopic lens or a wide angle lens. Usually the lens starts you off at a wide angle where you can see lots of stuff, then lets you zoom in to see more detail of the scene. These are called zoom lenses. Lenses that can't zoom are called "fixed angle" or "prime" lenses. You don't want those unless you know what you are doing.

Focal length. Not a word you're probably used to using but the idea is simply that smaller focal lengths = wide angles, and greater focal lengths = telescopic angles. Look at the diagram and it'll make sense.

Optical vs. Digital zoom. A telescopic lens squishes light and lets you see stuff from far away as if it were close by. This is called "optical zooming" because the lens is zooming into something by squishing light in the right way. Another way to zoom is called "digital zooming". In this case, the computer chip in the digital camera looks at the light in the pixel buckets on the camera sensor and guesses what you might see if the sensor had more pixel buckets. Sound complicated or confusing? It is, and that's why it doesn't work. Digital zoom is bad. Avoid it.

What's normal? On small cameras, an optical zoom range of 2x to 5x times is common. Be very skeptical if anybody tries to tell you a camera has a 10x zoom and it's a really small camera. Make sure it's "10x optical zoom" and not "10x digital zoom" (marketing people have gotten sneaky and tried to invent something called "enhanced optical zoom" which is optical zoom but with less detail... don't take it seriously.)

Keywords: whenever you see these words, you now know that people are talking about lenses: focal length, telescopic, tele, wide, wide angle, zoom, zoom range, optical zoom, digital zoom, enhanced zoom.

That's about it! Taken together with the information in my other hub, Top 10 Myths and Misconceptions about Buying a Digital Camera, you should have a pretty good idea about how to make a digital camera buying decision!