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Sigma has developed an integral-lens compact camera with the specs of a full-size, high end SLR.  In other words, the DP1 has all the functions of a full-spec digital SLR, packed into a compact camera with a built-in lens.  Here at sigma, we focused all our resources on achieving the nearly imposible.  Sigma is not about creating run-of-the-mill photographs, or pursuing image quality defined by numbers.  We give you a compact camera with the potential to capture exactly what you see and what you feel, with no compromize.

14 megapixel high definition digital camera, packing the full spec of a
DSLR into the body of a compact camera

Foveon X3 sensor

---oOo---

THE SIGMA DP1

The Sigma Corporation is pleased to announce the launch of the Sigma DP1 compact digital camera featuring a 14 megapixel FOVEON X3 direct image sensor (2652 × 1768 × 3 layers) as used in the Sigma SD14 digital SLR.

The DP1 is a completely new type of camera offering the full spec. and high image quality of a DSLR in the body of a compact camera. It is powered by the 14 megapixel Foveon X3 direct-image-sensor, which can reproduce high definition images rich in gradation and impressive three-dimensional detail.

It is possible to record images in RAW or the widely used JPEG in four resolution modes. It offers five Exposure modes and three Metering modes as well as being equipped with a built-in flash with the Guide Number of 6, hot shoe, neck strap and 2.5 inch TFT color LCD monitor with approx. 230,000 pixels.

The DP1 has the high resolution and functionality of an SLR, plus adaptability in terms of accessories, all built into a small body. A wide range of accessories, optical viewfinder [VF-11], Lens Hood [HA-11], and Electronic Flash [EF-140 DG] are available for the DP1 camera.

Development
Sigma introduced its digital SLRs, the SD9, SD10 and SD14 to the market in October 2002,
November, 2003 and March, 2007. They have established strong support from a wide range of photographers, both amateur and professionals. Recently, demand for a compact digital camera with portability as well as high image quality has increased. In order to meet this demand, the new DP1 has been developed as a completely new type of camera with high image quality and features that would not be out of place in a full spec DSLR.

Main features

SLR-SIZED IMAGE SENSOR 
The size of the image sensor used in the DP1 camera is 20.7mm x 13.8mm. It is approximately seven to twelve times larger than the 1/1.8inch to 1/2.5inch image sensors used in ordinary compact digital cameras. The pixel size of the image sensor is 7.8μm. The large photodiodes deployed at a large pixel pitch capture pure, rich light efficiently and give the DP1 its high resolution and richly-graduated tones.

FULL-COLOR IMAGE SENSOR
The DP1 uses the same 14 megapixel （2652×1768×3 layers）direct image sensor as the SD14. Utilizing the special features of silicon, which is penetrated to different depths by different wavelengths of light, this direct image sensor succeeds in full-color capture with the full RGB in a single-pixel location. Just like film, each photodiode captures all the RGB data, so no final-stage demosaicing is required. Brand-new “TRUE” image processing engine. The DP1 incorporates “TRUE” (Three-layer Responsive Ultimate Engine), the world’s first image processing engine suited for Foveon three silicon embedded layer direct image sensor. The unique image-processing algorithm, which has been developed throughout the development of the SD9, SD10 and SD14 cameras, is incorporated into “TRUE”. It enables high-speed image processing and high image quality.

16.6mm F4 LENS DESIGNED EXCLUSIVELY FOR THE DP1
The DP1 is equipped with a 16.6mm F4 lens, equivalent to 28mm on a 35mm SLR camera, which has been designed exclusively for DP1. The large-diameter of aspherical glass provides low distortion and high contrast images. It also offers superior peripheral brightness. The super multi-layer coating reduces flare and ghosting. It allows photographers to take pictures in difficult light conditions. This lens and SLR-sized image sensor provides natural shallow depth-of-field.

RAW FORMAT RECORDING
The DP1 includes JPEG recording format for convenience plus a RAW data (X3F) recording mode for retaining full image capture detail of the utmost quality. The RAW data format provides pure data for high-resolution images, and uses lossless compression for more compact, yet uncompromised, data files. The RAW data format of the DP1 keeps brightness and color data in a 1:1 ratio without relying on interpolation. Each pixel location captures the full color of RGB data, so in RAW, X3F files, brightness and color data can be kept in a 1:1 ratio without relying on interpolation. When the image is processed in Sigma Photo Pro, it will preserve the balance of the natural data for the best photos with the best image quality.

EXCLUSIVE SIGA PHOTOPRO SOFTWARE (Supplied with the DP1)
The DP1 comes complete with SIGMA Photo Pro software, a RAW image developer that converts all RAW data quickly and easily. Adjustments can be made in three separate modes. The X3F Mode 3 stores the original settings of the image at the point of capture. In the Auto Adjustment Mode, the software analyzes and automatically makes adjustments to the RAW data. The Custom Mode allows the photographer to make individual adjustments (exposure, contrast, shadow, highlight, saturation, sharpness and fill-light for example). The photographer can make changes easily and quickly by simply adjusting the slider controls within the software. The X3F Mode stores the original settings of the image at point of capture. Photographers` personal modifications can be saved to the RAW, X3F file for future use. SIGMA Photo Pro supports 8-bit TIFF, 16-bit TIFF, and JPEG file formats. The JPEG can be saved as YCbCr 4:4:4. It is also possible to half, or double the resolution when processing the image.

COMPACT AND LIGHTWEIGHT BODY
The DP1 has compact dimensions of 113.3mm/4.5in. (W) x 59.5mm/2.3in. (H) x 50.3mm/2.0in. (D) and weighs just 240g/8.5ounces. Its compact body and lightweight design makes it easy to carry everywhere.

THREE METERING MODES AND FIVE EXPOSURE MODES
The DP1 has three metering modes, Evaluative Metering, Center Weighted Average Metering and Spot Metering. It is also possible to select the exposure mode from Auto, Program AE, Aperture Priority AE, Shutter Priority AE or Manual. Exposure compensation can be set in 1/3 stop increments from +3.0 to -3.0 stops and an auto bracketing function is also available.
Pop up (manual) built-in flash The DP1 is equipped with a pop up (manual) built-in flash featuring guide number of 6 (ISO100 / m). It is possible to use Normal Flash, Red-Eye Reduction Flash and Slow Synchro Mode. It also features flash exposure compensation in 1/3 stops increments.

AF AREA SELECTION
The AF area of the DP1 is equipped with 9 focusing points and it is possible to manually select the desired focusing point. The focusing distance is from 50cm to infinity, however, it is possible to shorten the minimum focusing distance to 30cm.

MANUAL FOCUS
Manual Focus is available for photographers who like to take more control, or for use when
autofocus or focus lock is not effective. It is also possible to magnify the display to ensure precise focusing.

RECORDING MOVIES
It is possible to record 30fps movies with QVGA (320 x 240). The digital zoom function can be used during movie shooting. A 1GB memory card (not supplied) allows approximately 30 minutes of movie recording.

LARGE 2.5" TFT COLOR LCD MONITOR
The DP1 camera features large 2.5 inch, 230,000 pixel TFT color LCD monitor. The LCD monitor displays 100% of the images, allowing the photographer to easily and accurately confirm the image compensation.

HOT SHOE
The DP1 camera is equipped with a hot shoe, allowing use of the dedicated external flashgun
EF-140 DG (optional) or high performance view finder VF-11 (optional). EF-500 DG and EF-530 DG flashgun series can be used in manual mode only.

DEDICATED LENS HOOD
This optional lens hood blocks out extraneous light. A hood adapter, designed to accept a 46mm lens filter, is included.

From Wikipedia, the free encyclopedia:

• All text is available under the terms of the GNU Free Documentation License. (See Copyrights for details.) 

The Foveon X3 sensor is a CMOS image sensor for digital cameras, designed by Foveon, Inc. and manufactured by National Semiconductor and Dongbu Electronics. It uses an array of photosites, each of which consists of three vertically stacked photodiodes, that are organized in a two-dimensional grid. Each of the three stacked photodiodes responds to different wavelengths of light, i.e., each has a different spectral sensitivity curve. This is due to that fact that different wavelengths of light penetrate silicon to different depths. The signals from the three photodiodes are then processed, resulting in data that provides the three additive primary colors, red, green, and blue.

The development of the Foveon X3 technology is the subject of the 2005 book The Silicon Eye by George Gilder.

The diagram above shows how this works in graphic form. Depicted on the left is the absorption of colors of the spectrum according to their wavelength as they pass through the silicon wafer. On the right, a Foveon X3 layered sensor stack in the silicon wafer for each output pixel is shown depicting the colors it detects at each absorption level. The color purity and intensity of blue, green and red depicted for the sensors are for ease of illustration. In fact, the attributes of each output pixel that are reported by a camera using this sensor result from the camera's image processing algorithms that employ a matrix process to construct the single RGB color from the data sensed by the photodiode stack.

Because the depth in the silicon wafer of each of the three layer Foveon X3 sensors is less than five micrometres, it has negligible effect on focusing or chromatic aberration. However, because the collection depth of the deepest sensor layer (red) is comparable to collection depths in other silicon CMOS and CCD sensors, some diffusion of electrons and loss of sharpness in the longer wavelengths occurs.

As of January 2008 the Sigma SD14 digital SLR camera and the Polaroid X530  are the only consumer cameras shipping with a Foveon X3 sensor. The Sigma DP1, a compact digital camera, has been announced and should be available in March/april 2008 (we have one on order).

The Foveon X3 sensor is also used in the Hanvision HVDUO-5M and HVDUO-10M scientific and industrial cameras, though the sensors in these products, one of which is the same as in the Polaroid x530, are at end of life status. It was also used in the Sigma SD9 and SD10 consumer digital SLR cameras. These cameras are no longer in production. We have an SD9 but hardly every use it because the battery life is unacceptable low.

The operation of the Foveon X3 sensor is quite different from that of the Bayer filter image sensor more commonly used in digital cameras. In the Bayer sensor, each photosite in the array consists of a single light sensor (either CMOS or CCD) that, as a result of filtration, is exposed to only one of the three primary colors, red, green, or blue. Constructing a full color image from a Bayer sensor requires demosaicing, an interpolative process in which the output pixel associated with each photosite is assigned an RGB value based on the level of red, green, and blue reported by those photosites adjacent to it. The Foveon X3 sensor creates its RGB color output for each photosite by combining the outputs of each of the stacked photodiodes at each of its photosites. This operational difference results in several significant consequences.

Because demosaicing is not required for the Foveon X3 sensor to produce a full-color image, the color artifacts ("colored jaggies") associated with that process are not seen. The separate anti-aliasing filter commonly used  to mitigate those artifacts in a Bayer sensor is not required. This is because little aliasing occurs when the photodiodes for each color, with the assistance of the microlenses  integrate the optical image over a region almost as big as the spacing of sensors for that color.

Another difference is that more of the photons entering the camera will be detected by the Foveon X3 photosensor than is possible with a mosaic sensor. This is because each of the color filters overlaying each photosite of a mosaic sensor passes only one of the primary colors, absorbing the other two. The absorption of these colors reduces the total amount of light gathered by the sensor and destroys much of the information about the color of the light impinging on each sensor element. Although the Foveon X3 has greater light gathering ability, the color-indicating information in the sensor's raw data requires "aggressive" matrixing to produce color data in a standard color space, which can increase noise in low-light situations.

According to Sigma Corporation, "there has been some controversy in how to specify the number of pixels in Foveon sensors."^[18] The argument has been over whether sellers should count the number of photosites, or the total number of photodiodes, as a megapixel count, and whether either of those should be compared with the number of photodiodes in a Bayer filter sensor or camera as a measure of resolution.

For example, the dimensions of the photosite array in the sensor in the Sigma SD10 camera are 2268 × 1512, and the camera produces a native file size of those dimensions (times three color layers). This amounts to approximately 3.4 million three-color pixels. However, it has been advertised as a 10.2 MP camera by taking account of the fact that each photosite contains stacked red, green, and blue color sensing photodiodes, or pixel sensors (2268 × 1512 × 3). By comparison, the dimensions of the photosite array in the 10.2 MP Bayer sensor in the Nikon D200 camera are 3872 × 2592, but there is only one photodiode, or one pixel sensor, at each site. The cameras have equal numbers of photodiodes, and produce similar RAW data file sizes, but the Bayer filter camera produces a larger native file size via demosaicing.

However, the actual resolution produced by the Bayer sensor is more complicated than the count of its photosites, or its native file size, might suggest. The reason has to do with both the demosaicing and the separate anti-aliasing filter commonly used to reduce the occurrence or severity of color moiré patterns that the mosaic characteristic of the Bayer sensor produces. The effect of this filter is to blur the image output of the sensor, thus producing a lower resolution than the photosite count would seem to imply. This filter is largely unnecessary and not used with the Foveon X3 sensor. The earliest camera with a Foveon X3 sensor, the Sigma SD9, showed visible luminance moiré patterns, but not color moiré. Subsequent X3-equipped cameras have less aliasing because they include microlenses, which provide an effective anti-aliasing filter by averaging the optical signal over an area commensurate with the sample density, which is not possible in any color channel of a Bayer-type sensor. Aliasing from the Foveon X3 sensor is "far less bothersome because it's monochrome" according to Norman Koren. Therefore, in theory, it is possible for a Foveon X3 sensor with the same number of photodiodes as a Bayer sensor and no separate anti-aliasing filter to attain a higher spatial resolution than that Bayer sensor. More typically, independent testing has determined that the 10.2 MP array of the Foveon X3 sensor in the Sigma SD10 produces the resolution of at least 5 MP or 6 MP, and (at least at low ISO film speed equivalents) 7.2 MP  Bayer sensor.

With the introduction of the Sigma SD14, the 14 MP (4.7 MP red + 4.7 MP green + 4.7 MP blue) Foveon X3 sensor resolution is being compared favorably by reviewers to that of 10 MP Bayer sensors. For example, Mike Chaney of ddisoftware says, "the SD14 produces better photos than a typical 10 MP dSLR because it is able to carry sharp detail all the way to the 'falloff' point at 1700 LPI whereas contrast, color detail, and sharpness begin to degrade long before the 1700 LPI limit on a Bayer based 10 MP dSLR." Another article judges the Foveon X3 sensor as roughly equivalent to a 9 MP Bayer sensor.

The Foveon X3 sensor, as used in the Sigma SD10 camera, has been characterized by two independent reviewers as noisier than the sensors in some other DSLRs using the Bayer sensor at higher ISO film speed equivalents.^[ Another has noted higher noise during long exposure times. However, these reviewers offer no opinion as to whether this is an inherent property of the sensor or the camera's image processing algorithms.

More recently, one reviewer is judging the Sigma SD14 camera with the new 14 MP Foveon X3 sensor to have noise levels ranging from "very low" at the ISO 100 sensitivity equivalent to "Moderate" at the ISO 1600 equivalent using the camera'sRaw image format.

Sigma's SD14 site has galleries of full-resolution images showing the color produced by the current state of Foveon technology. The 14-MP Foveon chip produces 4.7 MP native-size RGB files; 14-MP Bayer filter cameras produce a 14 MP native file size by interpolation (demosaicing). Direct visual comparison of images from 12.7-MP Bayer sensors and 14.1 MP Foveon sensors show Bayer images ahead on fine monochrome detail, such as the lines between bricks on a distant building, but the Foveon images are ahead on color resolution.