Perhaps not yet, but the handwriting might be on the wall...
How
is a digital camera different from a film camera? What are pixels and
why are they important? What's the difference between optical and
digital zoom? What advantages do digital cameras have compared to film
cameras? Let's address these and other questions as we discuss digital
camera technology.
First a short history and overview of digital imaging...
The
technology began with television in the early 1950's when researchers
discovered how to convert video images to electrical signals for storage
on magnetic tape. In the 1970's electronic still photo cameras were
developed. These employed the first generations of solid-state image
sensors. By the late 1980's megapixel sensors were introduced - the
technology that paved the way to today's modern digital cameras.
Fundamentally,
film and digital cameras do the same thing. Both utilize camera lenses
to focus photographic images on a light sensitive medium where they are
stored for later retrieval. But the way each camera does this is
radically different.
Instead of capturing the image on film that
must be developed and printed, digital cameras measure light and color
characteristics using photodiodes built into a sensor - either a Charged
Coupled Device (CCD) or Complementary Metal-Oxide Semiconductor (CMOS).
An Analog-to-Digital Converter (ADC) then converts the signal to
binary, or digital, code. This code is sent to a Digital Signal
Processor (DSP) which adjusts photographic elements such as contrast and
color, and compresses the file for storage in the camera's memory,
compact flash card, or other memory device.
Digital cameras have
huge advantages when it comes to viewing and printing photos. It's
nearly instantaneous! We can immediately look at the picture on the
camera's LED screen, and if we don't like it, delete it and shoot again.
Or we download and view it on our computer's monitor. And the pictures
can be cropped or enhanced in minutes on the computer with photo
software and printed with a photo printer. Plus many digital cameras
have optional printer docks that don't require a computer at all.
What's a Pixel?
The
human eye perceives a nearly infinite blending of light and color which
high-quality film can approximate in a photograph. A digital image
however, is a binary code file that records these variations as elements
called pixels - short for picture elements.
Pixels are tiny
squares of light and color, that when assembled create a mosaic. And
like a mosaic, if the squares are small enough we see a smooth,
photographic image. However, if the pixels are too big the transitions
appear jagged or out of focus.
More pixels equal higher
resolution and photos with clearer sharper detail, much like when you
look at a mosaic with very small elements. For example, a 3 Megapixel
digital camera can produce pretty good snapshots and even enlargements
to about 8" X 10". But the more you enlarge, crop or otherwise
manipulate the image, the larger the pixels become, degrading the
photo's quality.
Size Really Does Matter
The number of
pixels the sensor produces is important, but so is the quality. The CCD
sensors of many small digital cameras are about the size of a small
fingernail, while some larger models will feature sensors up to about 1"
across. There are conflicting opinions about sensor type and size, and
the technology is advancing. But in general it can be argued that the
photodiodes in a tiny CCD probably won't be as powerful or effective as
an equal number in a larger sensor.
So unless your most important
considerations are the smallest and/or cheapest camera, you're likely
to be happier with the picture quality from a slightly larger model,
assuming both have the same number of pixels.
All Zooms Are Not Equal
The
specs say the camera has 3X optical and 4X digital for a 12X total
zoom. Sounds good, right? The answer is yes and no. Optical zoom works
like a telescope, while digital zoom crops the picture. Using these zoom
specs with our 3 megapixel camera example, here's what happens.
Optical
zoom brings the image 3X closer and uses all 3 million pixels. But
digital zoom crops up to 75% of what the lens sees and the sensor is
exposed to, so the photo now has about 750,000 pixels. Depending on
lighting and other conditions, using full digital zoom may not even get
you a good 4" X 6" print.
The Future of Digital Photography
The
last few years have seen tremendous advancement in digital imaging
technology. Some high-end digital cameras can now generate more than 12
million pixels and produce photos that rival medium-format film cameras.
As with all electronic technology, it's reasonable to expect even
better cameras will come to the market over the next several years.
Photography
"purists" will probably resist abandoning their film cameras as long as
possible. But when comparing convenience, flexibility and quality, it
seems inevitable that the majority of photographers will opt for digital
over film photography - and probably sooner rather than later.
nikon coolpix s3300 16 mp digital camera with 6x zoom nikkor glass lens and 2 7 inch lcd purple, nikon d5100 16 2mp cmos digital slr camera with 3 inch vari angle lcd monitor body only, gopro hd motorsports hero, sigma 17 70mm f2 8 4 dc macro os hsm lens for nikon mount digital slr cameras, leica 18176 v lux 40 14 1mp compact system camera with 3 0 inch tft lcd body only black, sony nex 5rkb 16 1 mp compact interchangeable lens digital camera with 18 55mm lens and 3 inch lcd black, canon eos 5d mark ii 21 1mp full frame cmos digital slr camera with ef 24 105mm f4 l is usm lens, toshiba camileo h30 full hd camcorder silverblack, tamron af 18 200mm f3 5 6 3 xr di ii ld aspherical if macro zoom lens for konica minolta and sony digital slr cameras, nikon coolpix s800c 16 mp digital camera with 10x optical zoom nikkor ed glass lens and 3 5 inch oled touch screen black, nikon coolpix s6300 16 mp digital camera with 10x zoom nikkor glass lens and full hd 1080p video blue, canon powershot sx50 hs 12 1 mp digital camera with 50x wide angle optical image stabilized zoom, sony hdrcx580v high definition handycam 20 4 mp camcorder with 12x optical zoom and 32 gb embedded memory 2012 model, pentax 21977 da 18 135mm f3 5 5 6 ed al if dc wr lens for pentax digital slr cameras, sony cyber shot dsc w690 16 1 mp digital camera with 10x optical zoom and 3 0 inch lcd black 2012 model, nikon coolpix s9100 12 1 mp cmos digital camera with 18x nikkor ed wide angle optical zoom lens and full hd 1080p video black, nikon coolpix l810 16 1 mp digital camera with 26x zoom nikkor ed glass lens and 3 inch lcd red, samsung hmx h300 full hd camcorder with 30x zoom black, tamron af 17 50mm f2 8 sp xr di ii vc vibration compensation zoom lens for canon digital slr cameras, canon
eos rebel t2i 18 mp cmos aps c sensor digic 4 image processor full hd
movie mode digital slr camera and ef s 18 135mm f3 5 5 6 is ud standard
zoom lens, canon
eos rebel t2i 18 mp cmos aps c sensor digic 4 image processor full hd
movie mode digital slr camera with 3 0 inch lcd and and ef s 18 55mm f3 5
5 6 is lens, panasonic lumix ts20 16 1 mp tough waterproof digital camera with 4x optical zoom orange, sony hdr cx210 high definition handycam 5 3 mp camcorder with 25x optical zoom black 2012 model, nikon 24 85mm f2 8 4 0d if af zoom nikkor lens for nikon digital slr cameras, fujifilm finepix s4000 14 mp digital camera with fujinon 30x super wide angle optical zoom lens and 3 inch lcd, evga geforce 8400 gs 512 mb ddr3 pci express 2 0 dvihdmivga graphics card 512 p3 1300 lr, nikon coolpix aw100 16 mp cmos waterproof digital camera with gps and full hd 1080p video orange, flip minohd video camera black 4 gb 1 hour 3rd generation, nikon 85mm f1 4d af nikkor lens for nikon digital slr cameras, sony
cyber shot dsc hx100v 16 2 mp exmor r cmos digital still camera with
carl zeiss vario tessar 30x optical zoom lens and full hd 1080 video, olympus om d e m5 16mp live mos interchangeable lens camera with 3 0 inch tilting oled touchscreen silver, nikon d600 24 3 mp cmos fx format digital slr camera with 24 85mm f3 5 4 5g ed vr af s nikkor lens, samsung hmx f80 flash memory hd digital video camcorder black, nikon 105mm f2 0d af dc nikkor lens for nikon digital slr cameras, nikon coolpix s3300 16 mp digital camera with 6x zoom nikkor glass lens and 2 7 inch lcd silver, canon eos digital rebel t3i 18mp slr camera 18 55mm 75 300mm super bundle, sony cyber shot dsc hx30v 18 2 mp exmor r cmos digital camera with 20x optical zoom and 3 0 inch lcd black 2012 model, canon
vixia hf m52 full hd 10x image stabilize camcorder wi fi enabled with
32 gb internal drive plus dual sdxc card slots and 3 0 inch touch lcd, sigma 24 70mm f2 8 if ex dg hsm af standard zoom lens for nikon digital slr cameras, canon
powershot sx40 hs 12 1mp digital camera with 35x wide angle optical
image stabilized zoom and 2 7 inch vari angle wide lcd premiere bundle
with 8 gb secure digital high capacity sdhc memory ca
No comments:
Post a Comment