Cameras 101
Ok, I know it looks long, but I tried my best to make it witty and entertaining. Grab a cup of coffee and be prepared to learn all there is to know about digital cameras.
Let’s face it, you need a new camera. You are either trying to take pictures with your cellphone or using one of those ancient floppy-disk-fed monstrosities from the 90s (see Figure 1). It’s 2007, ladies and gentlemen, and it’s time to catch up with today’s camera technology. Fortunately for you, cameras these days are cheap, powerful, and compact. Many have argued that camera technology has reached its peak. So it doesn’t matter if you want a full-fledged SLR or a simple point-and-shoot, now is the time.
Here I will outline what to look for in a camera. Megapixels, optical zoom, startup time, focus time, aperture, size, etc. There are actually many things to look for, but lucky for you it’s my job to clear it up. No, I’m not going to tell you to buy the most expensive one you find (most people only need a midrange model with a good sized memory card, and maybe a case if you’re prone to dropping things).
First thing I’ll explain is Megapixels (MP). As most people know, a camera contains a sensor made up of millions of capacitors that respond to light (you did know that, right? If not, look at Figure 2). Each capacitor is responsible for one pixel of light. So technically speaking, more sensors = better picture, yes? Actually, no. As the number of pixels increases, capacitor size has to decrease in order to fit in the same area. As they get smaller, they become less accurate and more susceptible to noise, the grainy artifacts you see in those crappy cell phone cameras. There is a sweet spot though, and most people say 5-7MP. Personally I find 5MP to be just fine. Beyond that and you will be limited by the quality of glass the camera uses.
Speaking of glass, this is the second most important thing to look for. If you use low-quality lenses, the light shining onto the sensor will be bjorked, leading to a crappy picture. Find something with OPTICAL zoom, preferably 3x (the industry standard). Digital zoom is a poor substitute; it crops the picture in order to “zoom” in. You should keep this option turned off (you will get better images cropping them later on your computer).
Another aspect of lenses is Aperture. An aperture is like the iris in the eye, it opens and closes to vary the amount of light. The bigger the aperture, the more light can be let in. This value is expressed as f/x.x, meaning the smaller the number, the bigger the aperture (see Figure 5 for an explanation). Most cameras have a maximum aperture of f/4. Shoot for something with f/2.8 or better.
Another thing to look for is ISO Sensitivity. This value is similar to that of film, a higher ISO means the sensor is more sensitive to light, and thus it requires less exposure time. In other words, your night shots won’t be as blurry. Find a camera with an ISO value of 800 or 1600.
There are also lesser factors that may or may not matter to you. These include startup time, focus time, video capabilities, screen size and overall size. If you like to take candid shots, you’ll want a camera that turns on instantly and focuses quickly. There’s nothing worse for a photographer than seeing the perfect shot disappear while your camera was trying to focus. Size is also relative to one’s needs. Obviously, you want it to be small, but you don’t want it to break in half if you drop it. My advice is to see it in person before you buy. Hold it, ask the salesman if you can put it in your purse or pocket. What’s the point of buying a fancy camera if it just sits at home?
Now that you’re a resident expert in camera specs, I’ll point you to one of two fields: point-and-shoots and dSLR’s.
First, the point-and-shoots. You want a camera that’s compact, yet takes decent pictures. 5 years ago these guys produced laughable images, even after the 10 seconds it took to focus correctly. If you used a flash, you’d notice that the poor thing asked you to wait 30 seconds between pictures to recharge… not cool. Today, these guys turn on, focus, and take the picture in a blink of an eye. No more lost candids. Most cameras can take a flash picture every 8-10 seconds; some can even do burst shots of 1-2 per second. Most come with video capabilities (for the Steven Spielberg in all of us). Look for a camera that can do 640x480 video at 30fps.. that’ll give you something you can actually watch and be proud of.
Let’s look at the Canon SD1000. Its $230 price tag puts it midpack. It boasts a 7.1MP sensor, 3x optical zoom with f/2.8 max aperture, 2.5” screen, 640x480 video and ISO 1600 in a tiny 0.78” package. That pretty much covers all the basics without breaking the bank. Throw in Canon’s legendary image quality and reliability and you got yourself a nifty little camera. Now you can be part of the he-who-posts-good-pictures-on-Facebook group. Say hello to Internet fame.
Next is digital SLRs (or dSLR). SLR stands for Single Lens Reflex. When you look through the viewfinder, you see exactly what will be taken. This is achieved by using a mirror and a prism to bounce the light through the lens to your eye. This is the “single lens” part of the acronym, signifying the one lens that both the sensor and your eye look through. When you take a picture, the mirror assembly flips up out of the way and the shutter opens, taking the picture. This is the “reflex” part. This is where the really cool noise comes from (and it makes your friends jealous).
With the advent of digital SLRs, the film backing was replaced with a sensor similar to what you’d see in a point-and-shoot. However, there is one big super duper important difference between the two, and that’s size (size matters- dun dun dun!). A typical point-and-shoot image sensor is about the size of an eraser head. A typical dSLR sensor is about the size of a stamp.. about 10 times larger. The larger size allows the capacitors to be larger and thus more accurate. This is where the magic happens. The image quality produced by one of these puppies will put any point-and-shoot to shame. (And don’t forget the cool mechanical sound!)
SLRs are also faster. How much faster? Well, the Canon EOS-1D Mk. III shoots at 10 pictures per second. That’s like, almost full motion video… at 10.1 megapixels. That’s 5 times the resolution of HD video. Compare that to a point-and-shoot’s paltry 1 picture per second burst. There’s no comparison.
Another benefit of SLRs is the ability to change lenses. Need to take a picture of an ant for National Geographic? Slap on a 50mm macro lens and git-er-done. Want to see Brett Favre’s face as he gets sacked? Slap on a 400mm telephoto and make the cover of Sports Illustrated (Figure 7). Whatever your photographic aspirations are, there is a lens out there for you.
Lets look at the hottest dSLR on the market right now, the Canon Digital Rebel XTi. It features a 10.1 MP self-cleaning sensor, a 2.5” LCD display, 3 frames per second speed, and a 27-image buffer. You can take one home for about $750. This camera has the most bang for the buck, and its sales record shows its success.
Ok, so here’s the question of the ages: why are you still using that piece of junk? Get with the times, those Kodak moments are slipping by every second.
Jon Stevens has been a professional photographer since 2003. He is a fourth year biomedical engineering student and currently works on the Bookstore marketing staff. His setup includes a Canon 20D, 16-35 f/2.8L, 70-200 f/4L, 50 Mk.I, Sigma flashes, B+W Filters and Manfrotto supports.