How Digital Cameras Work – A Clear Picture

How Digital Cameras Work – A Clear Picture

Have you noticed that everything in the electronics field is getting smaller and smaller, while at the same time becoming better and better? Cellphones are getting smaller, while the connections get better. Stereos and speakers are getting smaller, while the sound gets better. Digital cameras are in there, too. And it seems that the smaller they get, the more efficient they are. Why is that? Well, it’s the development of digital technology in conjunction with computer technology. The mating of these two sciences is producing some pretty cool digital cameras these days. Here, we’re going to show you how digital cameras work, and explain, in simple terms, how these two technologies merge to produce those wonderful images. And we’ll also look at the neat things you can do with them after you’ve taken them. So set your focus – here we go.

Why are digital cameras replacing film cameras?

Remember your old “point-and-shoot” camera? Remember taking your rolls of film down to the drugstore (or wherever you took them)? You had to wait a few days to see what beautiful pictures you’d taken (or which ones were out of focus, or where you’d cut off somebody’s head). Then came the “1-hour photo” shops, returning your finished pictures to you within hours. But that just wasn’t good enough. It didn’t satisfy your need for instant gratification (a need shared by people around the world). You want your pictures and you want them now!

Ok, already – here they are, within minutes. Now that’s better! And that’s why people all over the world are buying digital cameras and throwing out their old film cameras. Kodak must believe this is the trend because in 2004, they stopped selling film cameras – they only sell digital cameras now. So let’s look at some of the things you can do with a digital camera that you can’t do with a film camera:

• You can see your pictures within seconds of taking them.
• If you don’t like the picture you’ve taken, you can delete it – no more paying for pictures that didn’t turn out.
• Computer software programs allow you to do a variety of things with your photos, like file them in albums on the Internet, email them, manipulate them (crop out the ex-partner, or take out the red-eye), adjust the brightness, contrast or color, and much more.
• Digital cameras are smaller and lighter, easier to handle.
• The initial cost pays for everything at once, no more buying film and paying for developing for every roll.
• The CCD (the electronic part of the digital camera that converts your image into digital format) captures 70% of the available light, while photographic film captures only 2%. The result – brighter, sharper pictures.

That’s probably enough reasons for you to follow the trend towards digital photography. And if you’re a professional, and you like your old SLR camera, then you’ll love the new digital SLRs – they do everything your film camera will do, and more. And they’re still adaptable to all your professional uses; you can still change your camera lenses, and you can still mount them on camera tripods, and you can still attach external flashes to them, and you can still use your special effect filters on them. You get the picture!

How do digital cameras work?

So for those of you who aren’t professionals, let’s take a simple look at exactly how these modern-day marvels work. First we’ll look at the actual science. The main operating component in a digital camera is the CCD (charge-coupled device). A CCD has millions of light-sensitive elements, each representing a single point, called a pixel. When light hits the CCD, it triggers an electrical charge. The strength of each charge determines the color of the pixel, going from black, produced by no charge, to white, produced by a full charge.

Each charged particle is in analog format. The purpose of the CCD is to collect these charges and convert them to a digital format. The digital format is represented by bits. The more bits, the brighter the picture. The first digital cameras only had 8 bits, producing 256 levels of brightness. Today, they have 48 bits – a much brighter and sharper picture.

Although we’ve been talking about color here, CCDs actually create shades of gray, not color. There are several methods the digital camera uses to convert these grays to colors, but the process is fairly technical. Suffice it to say that a series of color filters are used, in conjunction with software in the camera, to produce the finished color picture.

We’ll mention resolution here, too. That’s what determines how clear or sharp your images are. Resolution is measured in pixels, each pixel representing one dot in the image. A million pixels is called a megapixel. If you take the number of horizontal pixels and the number of vertical pixels, and multiply them, that’ll tell you how many pixels there are in a square inch. For example, 640 x 480 is the basic resolution for most cameras.

All digital cameras have a pixel count, ranging from less than 1 megapixel up to as much as 5 megapixels today. That’ll probably go higher as technology advances. Remember, the more pixels there are, then the more detail that can be captured by the CCD, and the sharper your picture.

Another thing that directly affects the quality of the picture taken by a digital camera is the amount of light let in through the aperture. The aperture is the part that lets light into the camera, to be projected onto the CCD. The aperture works much like the pupil in your eye – it determines how much light is let in. To demonstrate this, just walk into a dark room, turn on the light, then look into the mirror – you can see your pupils getting smaller as they adjust to the brighter light.

The shutter is the part that opens as you push down the button when you’re ready to take your picture. If the shutter opens and closes quickly, then not much light is let in. Many cameras come with adjustable shutter speeds so you can control the amount of light let in and, subsequently, the resulting image. For more information on this subject, check out one of the many photography books and magazines – they’re full of helpful information.

If there’s no film, where are the images stored?

Good question. As we said, the images are converted by the CCD into digital format. That’s what allows them to be stored like computer data in the camera. Digital cameras have internal memories that store a limited number of images. Most of the better models today give you the option of adding a Memory Stick, which is a very small memory card that fits into a slot in the camera, and stores many images for later transfer to your computer.

There are several varieties of Memory Sticks today, like Smart Media and Compact Flash, but they all do the same thing – they store images. Think of them as tiny versions of your old 3½” floppy disks for your computer. But they’re a lot smaller and hold a lot more information than the old floppy did. They range in storage size from 4MB to 128MB. You’ll be able to save well over 100 pictures in your camera before you have to download them to your computer.

And downloading them is only the first step in the myriad of things you can do with those images once they’re in your computer. The professional can use them in their desktop publishing or computer graphics programs. The amateur can post them to one of the many websites available for photo storage. We told you earlier all the wonderful things you can do from there.

The digital camera accessory market is booming

Now you know basically how digital cameras work, perhaps you’d like to look into the wide world of accessories for the digital camera. As mentioned before, the professional can have a heyday with accessories – camera lenses, camera tripods, filters, bags, cases – the list goes on.

All the digital camera manufacturers recognize the potential of the accessory market. Check out this list and see if you don’t think that everybody’s trying to get a piece of the action: Canon, Casio, Fuji, Kodak, Nikon, Olympus, Pentax, Ricoh, Sony, Tamron – that’s just one quick run through the alphabet to find a few. There are more. So if you need accessories, you can go online and do your comparisons. Or you can go to one of the websites that give you ratings and reviews and see what others say about them. They all have their opinions about which one is best. But the only real way to discover what’s available and what’ll be best for your camera is to find out for yourself.

So, armed with all your digital camera knowledge, go shopping! Check out all the cool digital cameras and accessories. Check out the full scope of digital technology and capture the full image of how it can help you create the best, most-memorable pictures ever! And have fun!

About The Author

Gareth Marplesis a successfully published freelance copywriter, one of experience and diversity. He provides valuable tips and advice for consumers purchasing Sony digital camera accessories, Canon digital cameras and video camcorder repair. His numerous articles offer moneysaving tips and valuable insight on typically confusing topics.

This article on "How Digital Cameras Work" reprinted with permission.

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