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Sony Shoots For 4-Filter CCD, 8 Megapixel Camera
Artifex writes "If you're looking to spend about $1200 on a new digital camera, check out this Digital Photography Review look at Sony's upcoming 8 MegaPixel Cyber-shot DSC-F828. The most interesting thing isn't the number of pixels in this prosumer-grade camera, but its 4-color filter CCD system. ['Instead of the traditional RGB color filter array, the new CFA is made up of Red, Green, Blue and Emerald (like Cyan) color filters.'] I've always been a strict Canon fan, but this is making me think twice."
The camera (as almost all other) feature a single CCD. It does however have a 4 color fileter in front of it. BTW, Nikon had that for about 4-5 years now.
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The center frequencies to which our green and blue cones are sensitive are rather far apart, spectrally -- at least, compared to the G/R cones. Looks like the E sensor on this CCD is between the G/B cones.
(RGB sensors and emitters are generally calibrated to the center frequencies of our cones.)
This is a good idea that I'd never considered. More color information is always good, and we can always just define a transform to reduce it to human optics. If nothing else, this makes more data available for image correction and whatnot. I wonder if you can actually get the RGBE data out of the camera, or if it stores three-channel JPEGs like everyone else?
Well, in any case, tetrachromats rejoice.
Not necessarily. A photograph taken with a 35 MM can be blown up quite easily to 16x20 using a high end drum scanner (DS for example) It would not be as good as a 4x5 transaprency, but I have sen it done. At that size, for commercial uses, you would want at least a 4800x6000 resolution which is nearly 29 Mega-pixels.
What your printer at home produces and what commercial printing produce are 2 very different things. The screening technologies are very different and require different source data
It depends on how big you want to print the images. "Photo-quality" prints are typically 300 DPI. If you want to print a 4 x 6 image, that means you need and image that is 1200x1800 pixels to print at 300 DPI. If you want to print larger pictures, you need more mega-pixels. Also, the images in almost all digital cameras (except the Canon EOS1DS) is not 35mm. 35mm Film has an aspect ratio of 3:2. Digital cameras have the same aspect ratio as a normal computer monitor which is 4:3. When you are printing an image on 4x6 paper from a digitial camera, a small portion of the top and bottom is usually chopped off (unless you flattened the image). Digital cameras haven't yet passed 35mm film quality when it comes to how many pixels are captured. The closest is the Canon EOS-1DS(11 Megapixels) which rivals some consumer 400 speed films. But digital cameras still have a long way to go to rival 100 speed(or slower) film. But, the amount of detail captured in fine-grain 35mm film is almost never used by the typical consumer anyway. To make 4x6 prints, a 2 megapixel camera is about as good as a film camera.
The 10D is a great camera for the price, but readers should note that the $1499 MSRP is for the body only. Lenses must be purchased seperately. I read the article on the Sony a few days ago so I can't remember the focal length specs, but to get something similar on the Canon would require a serious cash outlay for lenses. In fact, I don't think there's a single Canon-mount lens that will cover that range. The EF 28-135mm f/3.5-5.6 IS lens might be closest, and is considered a bargain at around $500 - and that's inexpensive as far as lenses go. Most likely two lenses would be required to cover the Sony's focal length, and a good pair will run around $2500.
I should disclaim, I don't even own a 10D, although I plan to. I currently have a Powershot S400 because I need a small point-and-shoot, but I also want a full-featured camera for serious (albeit amateur) photography.
-- "Complacency is a far more dangerous attitude than outrage." -Naomi Littlebear
I did some Googling and found this guy has done some math:m .vs.dig ital.1.html
http://www.clarkvision.com/imagedetail/fil
Example:
Fujichrome Velvia has an lpm1.6 = 80 lpm. Equation 1 gives 10 megapixels for intensity detail, but
16 Megapixels is not that far away from the consumer market.
Me, I'll stick with my view camera. You'd need a few gigapixels to even approach an 8X10 contact print.
Color management would be handled the same as any other digital camera. Even though the CCD has a four color filter, the data is converted back to 3 color RGB (14 bit i might add... giving a slightly wider color gamut than current 12 bit digicams). If having a profile for your digicam is important I would recommend Monaco system's (now x-rite corporation) MonacoDColor application. This handy little app will allow you to perform easier color corrections simply by applying the cameras profile. It also intigrates well with Monaco EZColor (their prosumer monitor/printer calibrater).
so to sum it up... you do it the same way you always have... the new filter just gives more accurate color (epically since sony was well known for their clipped reds and yellows).
There's an excellent source of information about what "three primary colors" actually means at of Dave Trapp's Sequim (WA) Schools science department site. There's a relatively simple explanation of how color vision works, then a facinating and highly detailed in-depth discussion of the issue.
Some interesting notes from Mr. Trapp:
* "All three [signals] are equally sensitive to blue light, two have expanded ranges that include green and yellow light, and the third signal includes sensitivity to red light."
* "While these paradigms of primary colors have worked well for human printing and light uses for over a century, it is likely that the three primary colors are not descriptive of the world, but rather an artifact of our eyes, the tools we use to perceive the world."
* "The real world does not have primary colors!"
He also discusses how the world would be perceived differently if we evolved a fourth cone, sensitive in the UV region. Very cool stuff!
Interestingly, though, he's no longer teaching science, and details the reasons on his site. Anyone who's ever been driven crazy in a class taught by a guy named simply "Coach" (and who on this site hasn't?) will sympathize with this good teacher's plight.
Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
Brahmastra. Thanks that was a good job comparing the resolution of a 35mm to Digital. My experience with a Nikon 5000 is that it's 5 megapixels is good enough to create great looking 8x10 images. But there is more to good quality photography than the resolution of the film, or of the digital chip.
IMHO the quality of the lens is a the single largest determinant in a camera's ability for producing creative photos, and is an area where many digitals fall way too short.
The first thing I do when shooting a photograph is decide what the subject is. The next thing I do is frame the photo in such a way that anything that is not relevant to the subject is excluded from the photo. A good lens on a 35mm slr gives you the ability to use selective focus so that your subject is sharp, and everything else is a blur. For this technique to work you need a longish lens, and a wide aperture. Most point and shoots and digitals fall short in both categories. (My $1500 CAD Nikon included) So the thing that interested me most about this Sony was it's Carl Zeiss lens 28 - 200 mm equiv. F2.0 - F2.8 aperture.
Zeiss is famous for quality, and 105 mm lens, at f 2.8 is a beautiful combination for selective focus portraits.