Carver Mead turns eye to digital camera that rivals film
Foveon Inc. has built a high-end digital still camera that aims to rival the quality of analog film. The new startup is backed by Carver Mead, the inventor of the gallium-arsenide transistor, the silicon compiler and the artificial retina. Although Mead is not revealing details of the three analog VLSI image chips that are to be used in place of a charge-coupled device (CCD), he claims the Foveon camera spits out a 48-Mbyte, 4,000 x 4,000-pixel Photoshop file.
"We have worked very hard at Foveon to make our digital camera as good as a medium-format camera like a Hasselblad � but our camera has no moving parts, you can see the images you take with it instantly and it has many refinements . . . like our electronic loupe," said Mead. According to Mead, most digital still cameras interpolate two-thirds of the information they capture because the red, green and blue sensors are next to each other on the same CCD chip. In order to find the value of "red" at the pixel location of a "green" or "blue" pixel, a software interpolation step must be taken that averages the two red pixels on each side of the green or blue one.
Most digital cameras that use this method cannot measure the color of each part of the image directly, so they can't keep their pixels exactly aligned, which may result in artifacts like moire patterns. A few high-end digital cameras have solved that problem by sacrificing fast shutter speeds, either taking three shots per image (one each for red, green and blue) or scanning the image very slowly.
"Foveon's camera saves its images instantly to disk at any shutter speed and with no interpolation whatsoever," said Mead. The one-shot digital cameras that use interpolation also sacrifice three-fourths of their advertised resolution, since they must put green pixels on each side of each blue and red pixel; put red pixels on each side of blue and green pixels; and finally put blue pixels on each side of red and green ones. The most popular pattern for doing this is G-R-G, B-G-B, G-R-G.
That pattern ensures that each pixel of one color has the other two colors on each side of it, so that an average can be taken of the adjacent colors. Unfortunately, color is only directly measured for one of red, green or blue at each pixel, and the other two are interpolated. Thus, two-thirds of the colors are interpolated at each pixel location. In addition, conventional digital still cameras take four pixels in a square to directly measure the three colors in one pixel location.
Thus, of the 2 million pixel images advertised by today's state-of-the-art digital cameras, only one-third of the color is actually measured, since the other two colors are interpolated at each pixel location. In addition, the true resolution of the resulting image is really one-fourth of the total stated, or a half a million pixels, since adjacent red, green and blue pixels are set up in squares for easy interpolation.
Foveon avoids the color-interpolation problem by using a different technique, which splits the incoming light into three beams with a prism. The prism focuses the red light on a red sensor, the blue light on a blue sensor and the green light on a green sensor. That approach uses three times as many sensor chips, plus a multifaceted prism, but eliminates the moire-pattern problem.
Foveon attaches its sensors directly to the prism faces with glue that has the same index of refraction as the optical glass of the prisms, which eliminates the reflection and blurring problems of earlier designs. The company has a patent pending for the process it uses to attach its sensors directly to the prism.
Foveon employs analog VLSI chips modeled on the optical properties of real film. For instance, a magnified Foveon image will show grain, even though there is no film used anywhere in the process. Film has grain because the particles that change color when exposed to light are of varying sizes � big ones for dark areas with little detail and small ones for light areas of greater detail in an image. Foveon's sensors mimic that property of film.
"Our sensor works more like real film that has a gamma curve, which slopes smoothly from low-density to high-density areas, corresponding to the statistical distribution of coarse and fine grains, whereas CCDs have a completely linear curve," said Mead.
Foveon's analog VLSI chip dedicates fewer or greater resources to each particular area of an image, depending on the detail and light levels at that point. Consequently, the company does not say how many pixels per inch or bits per pixel are captured with its three chips because that depends on the part of the image in question. The one specification it does supply, however, hints at the size of its analog VLSI sensor: When it is ready to output a digital image to a printer, the camera produces a 48-Mbyte, 4,000- x 4,000-pixel Photoshop file.
The Foveon camera looks like a Wintel laptop with a squared-off Hula Hoop surrounding it and a Canon 28-mm to 70-mm lens attached to the front. You aim the laptop with attached lens at the subject and you see a continuous image on the left-hand side of the screen. When the user presses the space bar, the external flash is triggered, and a shot is taken and placed on the right-hand side of the screen.
Instead of zooming in on an image to inspect detail, the user can pop up a small "electronic-loupe" window on top of the image. Inside the window is a blown-up version of what's beneath it � just like the way a real loupe works. The electronic-loupe window is also enabled by the same process as the analog VLSI sensor, allowing it to mimic film grain by dedicating more chip resources to busier parts of an image.
When you pop off the skins of the proprietary parts of the Foveon camera � the Hula Hoop and a thin circuit board box beneath the laptop � you find a wealth of custom VLSI. In addition to the three analog VLSI sensors attached to the prism, an electronic shutter chip eliminates the last vestige of "moving parts" from the camera. "The only moving parts in our cameras are the electrons," said Mead.
Most of the custom chips, and there are many, were manufactured by National Semiconductor Corp., which holds a 45 percent stake in the company. Synaptics Inc., which was co-founded by Mead and Z-80 inventor Federico Faggin, holds a 30 percent stake. Synaptics has signed off all its patents and other intellectual property regarding digital imaging to Foveon.
Foveon also claims to have found second sources for its custom chips � even for the analog VLSI sensors. With its patents still pending on the sensors, Foveon is reluctant to reveal details about its design. However, Mead would say that the sensors are produced on standard digital CMOS fabrication lines that he has learned to tweak for analog VLSI.
|First, Let me check its expiry date. by rajeev22675|
from Best Photo of the Week
|Dairy Way by BodkinsBest|
from Best Astrophotography Landscape #4
YouTube channel Photoshop Cafe has shared a video detailing ten tips and tricks you can do to both fix and speed up Photoshop when it's running slow and sluggish.
It's not going to be the banger of the year, but it'll get a few laughs.
DJI has confirmed its drones won't be affected by the GPS 2019 week rollover.
Dogfish Head Craft Brewery has teamed up with Kodak to release a beer that's capable of doubling as a film developer.
The Diana Instant Square is a retro-inspired camera with manual controls that's fun to shoot in good light, but largely unpredictable in its operation.
Residents of a Paris street plagued by Instagrammers, selfie takers and music video crews are asking the city government for a weekend and evening ban to give them some peace.
The adapter plugs into the Osmo Pocket's USB Type-C port and features a 3.5mm TRS jack to plug in various external microphones.
Checkout allows Instagram users to select products for purchase and make payments directly in the app.
GauGAN as it's known, can create photorealistic images from basic drawings using the power of artificial intelligence.
The EOS RP is Canon's latest full-frame mirrorless camera, with diminutive dimensions and a diminutive price. Find out how it stacks up and get our thoughts in our early review.
Montana judge Dana L. Christensen has ruled the Republican National Committee did not infringe upon the copyright of photographer Erika Peterman after they took a photo from a Democratic candidate's Facebook page without permission and altered it to use in a derogatory promotional mailer.
Nikon has launched updates for three of its programs to address various bugs and glitches that could cause crashes and unwanted results.
LEE Filters has launched the LEE100, its next-generation filter holder that improves the design and looks in all the right places.
With the arrival of some much-needed sunshine and final production firmware for the Panasonic S1, we've been able to get outside and really start putting the camera through its paces.
Importing, culling and tagging photos is about to get a whole lot faster and look a whole lot better with the impending arrival of Photo Mechanic 6.
On its own, the FTZ adapter retails for $250 and when bundled it dropped the cost to just $150. Now, Nikon is offering it for free with all Z6, Z7 purchases in the United States.
Profoto said it spoke with Godox back at Photokina 2018 and continues to contact Godox in an effort to stop it from marketing its V1 light.
Product renders in Italian publication Notebook Italia show an unusual design that conceals all cameras with the help of a slider mechanism.
Canon says its new EF 400mm F2.8L IS III and EF 600mm F4L IS III lenses can suffer from an intermittent flickering when shooting video in M or Av modes with certain cameras.
Leica recently announced the Q2, a digital rangefinder with a fixed 28mm F1.7 lens. It's a heck of a lot of fun to shoot with, but is it right for you? Based on our time with the camera, and its specifications, we've examined how well-suited it is for common photography use-cases.
Now that our Panasonic Lumix S1R has final firmware, we couldn't wait to get out shooting with it - and we also tried the high-res mode, which combines files to get 187 megapixel images. Because sometimes, 47 megapixels just isn't enough.
In this article, travel and landscape photographer Mitch Green encourages us to spend more time in the the field.
the lens lacks any electronics whatsoever and is constructed entirely of glass and metal. Of course, that comes at the expense of weight — this thing weighs in at 1.1kg / 2.43lbs.
Drones can be useful tools in urban areas, where they're utilized for everything from news reporting to building inspections, but flying in these areas requires careful preparation. Here's what you need to know to do so safely.
Hasselblad has released a new cable release and USB double battery charger for its X1D medium format camera .
After a report published by NBC News, Flickr has taken heat for allegedly letting IBM 'scrape' photos for use in its facial recognition datasets. But the problem isn't what it seems on the surface.
Samyang has announced the impending arrival of the AF 85mm F1.4 FE lens for full-frame Sony cameras.
Some Photoshop shortcuts are simple and obvious. Others, not so much. Here are 15 shortcuts that are actually useful.
Twitter has redesigned its in-app camera for easier access from the timeline screen.
Independent cinema lens manufacturer SLR Magic has announced it will offer all of its existing MicroPrime range in the Fujifilm X mount and has even created a Fuji-specific 12mm lens.