Read these 8 Digital Camera History and Technology Tips tips to make your life smarter, better, faster and wiser. Each tip is approved by our Editors and created by expert writers so great we call them Gurus. LifeTips is the place to go when you need to know about Digital Camera tips and hundreds of other topics.
Our natural tendency is to buy a digital camera with the greatest resolution we can afford. The reasoning is, why get a 3 MP (megapixel) camera, when I can have a 5 MP camera? And to some extent, this makes sense.
However, before you buy that camera, consider your needs. How will you use the camera and the digital pictures it produces? If you will mostly share your pictures via e-mail or post them on your website, 5 MP is overkill? A 3 MP camera will provide all the resolution you need for e-mail and the Web, and even for the occasional 5” x 7” print.
Buying a camera with more resolution than you need has hidden costs. For example:
* All other things being equal, the higher the resolution, the higher the purchase price. You can afford a lot more features in a camera with lower resolution.
* Shooting higher resolution pictures requires larger memory cards to store the same number of pictures.
* The files from a 5 MP camera will require much more storage space than those from a 3 MP camera. That means they'll fill your hard drive twice as fast… or require twice as many CD's to store them.
If you're wondering just how much resolution you need (how many megapixels), here's an easy way to figure it out:
Find out the number of pixels there are on the camera's sensor array – both across and down. (This number will be in the manufacturer's specifications.) For example, Canon PowerShot S2 IS is a 5 MP camera. At its highest resolution, the CCD uses 2592 pixels x 1944 pixels.
Divide each number by 200. Using our Powershot S2 IS example, 2592 / 200 = 12.96 and 1944 / 200 = 9.72.
The resulting numbers tell you how large, in inches, a quality print you can get from the camera. So, the S2 IS should be able to provide you with good prints up to 10” x 13”.
Pixel is short for “picture element.” Each cell within a sensor array essentially creates one pixel. And each pixel is one little detail about the object being photographed. The total number of pixels a sensor array records is called “resolution.”
Imagine if you were asked to describe the entire history of the world from the dawn of man, in as much detail as possible, with just 300,000 words. Mesopotamia, China, Egypt, Babylon, Rome, Greece, the Zulu Empire, the Mongol Horde, the Vikings, the Renaissance, the Incas…
How could you possibly fit all that – and more - into 300,000 words? It's the same scenario with digital cameras. You can only fit so much detail into 640 pixels by 480 pixels (VGA resolution). That's why these low-resolution pictures look grainy and fuzzy. There are only 311,040 pixels to work with.
Now imagine you've been given 8 million words to describe world history. That's more than 25 times more words to cover the same topic. While you'll still have to leave things out, your description will be a whole lot more detailed, won't it?
Today's 7 and 8MP (megapixel) ultra-compacts – some almost as small as a credit card – are a far cry from the first invented digital camera.
Back in 1975, newly hired Eastman Kodak engineer, Steven Sasson, was tasked with making use of a new kind of imager: the CCD (charge coupled device). Sasson's answer was as big as a toaster and built from scavenged components, but would eventually change the world.
The camera's .01MP black and white images weren't much to look at, but someone at Eastman Kodak saw the potential, because Kodak has, over the years, been granted more than 1,000 patents related to digital imaging.
In spite of the invention, it wasn't Kodak that marketed the first filmless camera to consumers. Instead, it was Sony, whose TV-technology-based Mavica was introduced in 1981. It was nearly another 20 years before Eastman Kodak entered the consumer digital camera market.
Most digital cameras save images in only one file type: JPEG (Joint Photographers Expert Group). But even if this is the case with your camera, read on, because you're going to discover something disturbing about JPEG files. And what you can do about it.
If you own a professional digital camera, or one designed for serious enthusiasts, you'll probably have one or two other options: TIFF (Tagged Image File Format) and RAW (Raw isn't an acronym. It denotes files that have been saved exactly as they were recorded by the image sensor.)
JPEG files have an advantage that make them the favorite of most camera manufacturers - they compress. That's why your camera probably offers three options for saving JPEG images - typically they are Small, Medium and Large. Each option indicates a different degree of compression… and compression actually throws picture data away.
For most snapshooters, this isn't a problem, because only “duplicate” data is lost. But the greater the compression, the greater the amount of data that's discarded… and the greater the amount of fine detail that's lost.
TIFF files, on the other hand, are larger, because they're not compressed. That means you can save many fewer TIFF files on a memory card than JPEG files. How many less? A 6 MP Nikon D100 can store about 150 – 175 JPEG files with minimal compression on a 512 MB compact flash card. The same card will only hold about 27 6 MP TIFF files.
In other words, you can get more than six times as many JPEG's in the same amount of memory. That's about 3 MB per JPEG file vs. about 19 MB per TIFF.
Finally, there are RAW files. They're about half the size of TIFF files, and have one other big advantage. Because they contain the data just as the image sensor “saw” it – unprocessed in any way - professionals find that these files provide them with the best opportunity to recreate on paper (or on screen) the scene as they envisioned it when they shot it.
Digital camera history is marked by two trends in particular: a rapid rise in technology, and a rapid drop in prices. The technology you can have in a digital camera today was undreamed of less than 20 years ago… and the price for that technology is chicken feed compared to the cost of digital cameras just ten years ago.
* In 1991, Kodak introduced the DCS100, a 1.3 megapixel professional digital camera built on a modified Nikon F3 body. This was the first true production model digital camera. It sold for over $25,000.00.
* Apple Computer reached a milestone in 1994 with the QuickTake 100. This was the first consumer digital camera priced under $1,000.00. The QuickTake 100 could store up to eight VGA resolution (640 x 480) images in its internal memory. It featured a 50 mm lens and built-in flash.
* 1996 saw the introduction of Kodak's DC-120, the first consumer 1 MP digital camera to break the $1,000.00 barrier.
Now fast-forward just ten years… and consider what's available to you in 2006:
* A search for 6 MP point-and-shoot digital cameras at one photo store's website returned more than 50 models… with prices staring below $200.00.
The key piece of digital camera technology is the image sensor. Nearly all digital cameras employ either a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) as their image sensor, and each technology has its pros and cons.
The CMOS has the advantage in cost and power consumption, while the CCD has an edge in image quality. However, advances in the manufacture of each are narrowing the gaps to varying degrees.
Both sensors have similarities. Within a digital camera both are set up in “sensor arrays” with many individual cells each picking up one little bit of light. The cells in an array are set up almost like a checkerboard, and each picks up only one color of light - either red, blue or green.
Fifty percent of the cells are attuned to green light, while 25% detect blue and 25% detect red. The light hitting each cell is converted to a digital signal and that information is interpreted by the camera's processor and stored in memory (usually a removable flash memory card).
Image sensors are like the film in a traditional camera. They're sensitive to light, and the image is recorded there when the shutter opens.
If you plan to use your digital camera outside - possibly exposing it to heavy rain or snow or for use at the beach - a waterproof digital camera makes sense. Both Olympus and Pentax have models that fit the bill. And they're even okay to submerge. The Olympus can be submerged to 10 feet for up to an hour, while the Pentax is rated to withstand depths of five feet for a half-hour.
However, if you want to really take your camera in the water, you'll have to go a different route. Companies like Bonica and Sea & Sea make cameras with waterproof housings that can withstand pressures up to 180' below the surface. And companies such as Aquapac and Ikelite – as well as some camera manufacturers – offer waterproof housings that enable you to use more conventional digital cameras at similar depths.
If you want to take your camera with you on that Caribbean snorkling adventure, one of these options will serve you better.
Looking at the past of digital photography, we can catch a glimpse of its future. But combine the past with the present, and we can get a pretty good look at where things are going.
It was only in 1991 that Kodak introduced the 1.3 MP DCS100. At the time, it was revolutionary, and cost over $25,000. Even closer in time, February 2002 saw the introduction of Nikon's much-anticipated D100. For $1,999, you could own a 6 MP d-SLR!
Today, entry-level d-SLR's offer much more than their predecessors… for quite a bit less. Many – Like the Pentax K100D and the Nikon D50 - are still 6 MP cameras, but that's beginning to change. The Canon Digital Rebel XT and the Olympus Evolt E-330 boast 8 MP CMOS (Olympus calls theirs a Live MOS) sensors.
All four of these models can record images as JPEG and RAW files – and the Olympus offers TIFF as well. All four offer shutter speeds of at least 1/4000 sec. – 30 sec. All four have at least three exposure metering modes (some variation of multi-pattern, center-weighted and spot). And all four offer at least four exposure modes (auto, aperture priority, shutter priority and manual), as well as pre-programmed scene modes.
All four have ISO ranges of at least 200 – 1600, multi-point auto-focus and boast high speed USB 2.0 connectivity. The Pentax and Nikon record to Secure Digital (SD) cards, the Canon records to Compact Flash (CF) cards and the Olympus has dual slots, accommodating both.
|Jennifer Mathes, Ph.D.|