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84-452: The X10 was noted for its 2/3 inch type sensor, "twice as large as those used in almost all traditional compacts" at the time, and its EXR colour filter layout , allowing either greater dynamic range or lower noise to be recorded in an image of reduced resolution, as well as a conventional full resolution image. The X10's optical tunnel viewfinder zooms in synchrony with the 28-112mm equivalent, f/2.0 to f/2.8 maximum aperture zoom lens that

168-400: A combination of Rayleigh scattering and a moderate amount of melanin in the iris' anterior border layer. Hazel eyes often appear to shift in color from a brown to a green. Although hazel mostly consists of brown and green, the dominant color in the eye can either be brown/gold or green. This is why hazel eyes can be mistaken as amber and vice versa. The combination can sometimes produce

252-489: A connection to the brain via the optic nerve . The remaining components of the eye keep it in its required shape, nourish and maintain it, and protect it. Three types of cells in the retina convert light energy into electrical energy used by the nervous system : rods respond to low intensity light and contribute to perception of low-resolution, black-and-white images; cones respond to high intensity light and contribute to perception of high-resolution, coloured images; and

336-472: A mosaic) and arrangements of three separate CCDs (one for each color) doesn't need demosaicing. On June 14, 2007, Eastman Kodak announced an alternative to the Bayer filter: a colour-filter pattern that increases the sensitivity to light of the image sensor in a digital camera by using some panchromatic cells that are sensitive to all wavelengths of visible light and collect a larger amount of light striking

420-565: A multicolored iris, i.e., an eye that is light brown/amber near the pupil and charcoal or dark green on the outer part of the iris (or vice versa) when observed in sunlight. Definitions of the eye color hazel vary: it is sometimes considered to be synonymous with light brown or gold, as in the color of a hazelnut shell. Around 18% of the US population and 5% of the world population have hazel eyes. Hazel eyes are found in Europe , most commonly in

504-581: A personal computer. The cheaper the camera, the fewer opportunities to influence these functions. In professional cameras, image correction functions are completely absent, or they can be turned off. Recording in Raw-format provides the ability to manually select demosaicing algorithm and control the transformation parameters, which is used not only in consumer photography but also in solving various technical and photometric problems. Demosaicing can be performed in different ways. Simple methods interpolate

588-404: A preference for the zoom ring experience, and TechCrunch referred to the viewfinder shading as "more quaint than problematic". PC Magazine bemoaned the absence of visual focus confirmation, and lack of an ability to have auditory focus confirmation without also playing an artificial shutter sound clip. However, they also wrote that the camera "nailed the focus quickly and consistently", and rated

672-510: A saccade and larger than a microsaccade, subtend up to one tenth of a degree. Researchers vary in their definition of microsaccades by amplitude. Martin Rolfs states that 'the majority of microsaccades observed in a variety of tasks have amplitudes smaller than 30 min-arc'. However, others state that the "current consensus has largely consolidated around a definition of microsaccades that includes magnitudes up to 1°." The vestibulo-ocular reflex

756-536: A solid gold hue. Even though amber is similar to gold, some people have russet or copper colored amber eyes that are mistaken for hazel, though hazel tends to be duller and contains green with red/gold flecks, as mentioned above. Amber eyes may also contain amounts of very light gold-ish gray. People with that eye color are common in northern Europe , and in fewer numbers in southern Europe, the Middle East , North Africa , and South America . Hazel eyes are due to

840-434: A static contrast ratio of around 100:1 (about 6.5 f-stops ). As soon as the eye moves rapidly to acquire a target ( saccades ), it re-adjusts its exposure by adjusting the iris, which adjusts the size of the pupil. Initial dark adaptation takes place in approximately four seconds of profound, uninterrupted darkness; full adaptation through adjustments in retinal rod photoreceptors is 80% complete in thirty minutes. The process

924-480: A surgical area, such as cornea , cataracts , laser , retina , or oculoplastics . Eye care professionals include: Almost all mammals have brown or darkly-pigmented irises. In humans, brown is by far the most common eye color, with approximately 79% of people in the world having it. Brown eyes result from a relatively high concentration of melanin in the stroma of the iris, which causes light of both shorter and longer wavelengths to be absorbed. In many parts of

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1008-403: A volume of 6 cubic centimetres (0.37 cu in). The eyeball grows rapidly, increasing from about 16–17 mm (0.63–0.67 in) diameter at birth to 22.5–23 mm (0.89–0.91 in) by three years of age. By age 12, the eye attains its full size. The eye is made up of three coats, or layers, enclosing various anatomical structures. The outermost layer, known as the fibrous tunic ,

1092-466: Is a color filter array (CFA) for arranging RGB color filters on a square grid of photosensors. Its particular arrangement of color filters is used in most single-chip digital image sensors used in digital cameras, and camcorders to create a color image. The filter pattern is half green, one quarter red and one quarter blue, hence is also called BGGR , RGBG , GRBG , or RGGB . It is named after its inventor, Bryce Bayer of Eastman Kodak . Bayer

1176-441: Is a reflex eye movement that stabilizes images on the retina during head movement by producing an eye movement in the direction opposite to head movement in response to neural input from the vestibular system of the inner ear, thus maintaining the image in the centre of the visual field. For example, when the head moves to the right, the eyes move to the left. This applies for head movements up and down, left and right, and tilt to

1260-556: Is also known as Tetracell by Samsung , 4-cell by OmniVision , and Quad CFA (QCFA) by Qualcomm . On March 26, 2019, the Huawei P30 series were announced featuring RYYB Quad Bayer, with the 4x4 pattern featuring 4x blue, 4x red, and 8x yellow. On February 12, 2020, the Samsung Galaxy S20 Ultra was announced featuring Nonacell CFA. Nonacell CFA is similar to Bayer filter, however adjacent 3x3 pixels are

1344-466: Is also known for his recursively defined matrix used in ordered dithering . Alternatives to the Bayer filter include both various modifications of colors and arrangement and completely different technologies, such as color co-site sampling , the Foveon X3 sensor , the dichroic mirrors or a transparent diffractive-filter array. Bryce Bayer 's patent (U.S. Patent No. 3,971,065 ) in 1976 called

1428-417: Is an area of 4.17 steradians or 13700 square degrees for binocular vision. When viewed at large angles from the side, the iris and pupil may still be visible by the viewer, indicating the person has peripheral vision possible at that angle. About 15° temporal and 1.5° below the horizontal is the blind spot created by the optic nerve nasally, which is roughly 7.5° high and 5.5° wide. The retina has

1512-579: Is another name for edge blurring that occurs in an on/off pattern along an edge. This effect occurs when the demosaicing algorithm averages pixel values over an edge, especially in the red and blue planes, resulting in its characteristic blur. As mentioned before, the best methods for preventing this effect are the various algorithms which interpolate along, rather than across image edges. Pattern recognition interpolation, adaptive color plane interpolation, and directionally weighted interpolation all attempt to prevent zippering by interpolating along edges detected in

1596-482: Is caused by the combination of: 1) an amber or light brown pigmentation in the stroma of the iris (which has a low or moderate concentration of melanin) with: 2) a blue shade created by the Rayleigh scattering of reflected light. Green eyes contain the yellowish pigment lipochrome . The inheritance pattern followed by blue eyes was previously assumed to be a mendelian recessive trait, however, eye color inheritance

1680-493: Is changed for near focus (accommodation) and is controlled by the ciliary muscle. Between the two lenses (the cornea and the crystalline lens), there are four optical surfaces which each refract light as it travels along the optical path. One basic model describing the geometry of the optical system is the Arizona Eye Model. This model describes the accommodation of the eye geometrically. Photons of light falling on

1764-411: Is composed of the cornea and sclera , which provide shape to the eye and support the deeper structures. The middle layer, known as the vascular tunic or uvea , consists of the choroid , ciliary body , pigmented epithelium and iris . The innermost is the retina , which gets its oxygenation from the blood vessels of the choroid (posteriorly) as well as the retinal vessels (anteriorly). The spaces of

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1848-440: Is exerted on the globe that causes it to turn, in almost pure rotation, with only about one millimeter of translation. Thus, the eye can be considered as undergoing rotations about a single point in the centre of the eye. The approximate field of view of an individual human eye (measured from the fixation point, i.e., the point at which one's gaze is directed) varies by facial anatomy, but is typically 30° superior (up, limited by

1932-442: Is higher. The raw output of Bayer-filter cameras is referred to as a Bayer pattern image. Since each pixel is filtered to record only one of three colors, the data from each pixel cannot fully specify each of the red, green, and blue values on its own. To obtain a full-color image, various demosaicing algorithms can be used to interpolate a set of complete red, green, and blue values for each pixel. These algorithms make use of

2016-459: Is nonlinear and multifaceted, so an interruption by light exposure requires restarting the dark adaptation process over again. The human eye can detect a luminance from 10 cd/m , or one millionth (0.000001) of a candela per square meter to 10 cd/m or one hundred million (100,000,000) candelas per square meter. (that is it has a range of 10 , or one hundred trillion 100,000,000,000,000, about 46.5 f-stops). This range does not include looking at

2100-467: Is now recognized as a polygenic trait , meaning that it is controlled by the interactions of several genes. Blue eyes are predominant in northern and eastern Europe, particularly around the Baltic Sea . Blue eyes are also found in southern Europe, Central Asia , South Asia , North Africa and West Asia . Approximately 8% to 10% of the global population have blue eyes. A 2002 study found that

2184-430: Is transparent and more curved and is linked to the larger posterior segment, composed of the vitreous, retina, choroid and the outer white shell called the sclera. The cornea is typically about 11.5 mm (0.45 in) in diameter, and 0.5 mm (500 μm) in thickness near its centre. The posterior chamber constitutes the remaining five-sixths; its diameter is typically about 24 mm (0.94 in). An area termed

2268-551: Is typically a thin layer directly in front of the sensor, and works by effectively blurring any potentially problematic details that are finer than the resolution of the sensor. The Bayer filter is almost universal on consumer digital cameras. Alternatives include the CYGM filter ( cyan , yellow , green, magenta ) and RGBE filter (red, green, blue, emerald ), which require similar demosaicing. The Foveon X3 sensor (which layers red, green, and blue sensors vertically rather than using

2352-407: Is what is known and seen as false coloring. Typically this artifact manifests itself along edges, where abrupt or unnatural shifts in color occur as a result of misinterpolating across, rather than along, an edge. Various methods exist for preventing and removing this false coloring. Smooth hue transition interpolation is used during the demosaicing to prevent false colors from manifesting themselves in

2436-789: The Netherlands and the United Kingdom , and have also been observed to be very common among the Low Saxon speaking populations of northern Germany. Green eyes are most common in Northern , Western and Central Europe . Around 8–10% of men and 18–21% of women in Iceland and 6% of men and 17% of women in the Netherlands have green eyes. Among European Americans , green eyes are most common among those of recent Celtic and Germanic ancestry, with about 16%. The green color

2520-425: The ciliary muscles surrounding the lens; this process is known as "accommodation". Accommodation narrows the inner diameter of the ciliary body, which actually relaxes the fibers of the suspensory ligament attached to the periphery of the lens, and also allows the lens to relax into a more convex, or globular, shape. A more convex lens refracts light more strongly and focuses divergent light rays from near objects onto

2604-404: The eye movements , the seventh controls the movement of the upper eyelid . The six muscles are four recti muscles – the lateral rectus , the medial rectus , the inferior rectus , and the superior rectus , and two oblique muscles the inferior oblique , and the superior oblique . The seventh muscle is the levator palpebrae superioris muscle . When the muscles exert different tensions, a torque

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2688-647: The iPhone 6 's front camera released in 2014. Quad Bayer is similar to Bayer filter, however adjacent 2x2 pixels are the same color, the 4x4 pattern features 4x blue, 4x red, and 8x green. For darker scenes, signal processing can combine data from each 2x2 group, essentially like a larger pixel. For brighter scenes, signal processing can convert the Quad Bayer into a conventional Bayer filter to achieve higher resolution. The pixels in Quad Bayer can be operated in long-time integration and short-time integration to achieve single shot HDR, reducing blending issues. Quad Bayer

2772-413: The assumption that the color of an area in the image is relatively constant even under changing light conditions, so that the color channels are highly correlated with each other. Therefore, the green channel is interpolated at first then the red and afterwards the blue channel, so that the color ratio red-green respective blue-green are constant. There are other methods that make different assumptions about

2856-408: The better-focused centre. In the eye, the pupil serves this purpose by constricting while the eye is focused on nearby objects. Small apertures also give an increase in depth of field , allowing a broader range of "in focus" vision. In this way the pupil has a dual purpose for near vision: to reduce spherical aberration and increase depth of field. Changing the curvature of the lens is carried out by

2940-442: The blue value. This simple approach works well in areas with constant color or smooth gradients, but it can cause artifacts such as color bleeding in areas where there are abrupt changes in color or brightness especially noticeable along sharp edges in the image. Because of this, other demosaicing methods attempt to identify high-contrast edges and only interpolate along these edges, but not across them. Other algorithms are based on

3024-476: The brain to determine the depth and distance of an object, called stereovision, and gives the sense of three-dimensionality to the vision. Both eyes must point accurately enough that the object of regard falls on corresponding points of the two retinas to stimulate stereovision; otherwise, double vision might occur. Some persons with congenitally crossed eyes tend to ignore one eye's vision, thus do not suffer double vision, and do not have stereovision. The movements of

3108-401: The brow), 45° nasal (limited by the nose), 70° inferior (down), and 100° temporal (towards the temple). For both eyes, combined ( binocular vision ) visual field is approximately 100° vertical and a maximum 190° horizontal, approximately 120° of which makes up the binocular field of view (seen by both eyes) flanked by two uniocular fields (seen by only one eye) of approximately 40 degrees. It

3192-428: The camera 4.0 out of 5. At least some early-release X10 specimens had a flaw that could make "white orbs" appear in images. As a first response, in early February 2012, Fujifilm released a firmware update to mitigate the issue, but this was not successful. Fujifilm then also modified the sensor and in early March announced a sensor replacement program for any cameras affected by the issue. Tech publication DPReview judged

3276-423: The ciliary body by the suspensory ligament ( zonule of Zinn ), made up of hundreds of fine transparent fibers which transmit muscular forces to change the shape of the lens for accommodation (focusing). The vitreous body is a clear substance composed of water and proteins, which give it a jelly-like and sticky composition. Each eye has seven extraocular muscles located in its orbit . Six of these muscles control

3360-416: The close spacing of similarly colored photosites. The Fujifilm X-Trans CMOS sensor used in many Fujifilm X-series cameras is claimed to provide better resistance to color moiré than the Bayer filter, and as such they can be made without an anti-aliasing filter. This in turn allows cameras using the sensor to achieve a higher resolution with the same megapixel count. Also, the new design is claimed to reduce

3444-438: The color value of the pixels of the same color in the neighborhood. For example, once the chip has been exposed to an image, each pixel can be read. A pixel with a green filter provides an exact measurement of the green component. The red and blue components for this pixel are obtained from the neighbors. For a green pixel, two red neighbors can be interpolated to yield the red value, also two blue pixels can be interpolated to yield

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3528-406: The dark. The latter value decreases slowly with age; older people's eyes sometimes dilate to not more than 5–6mm in the dark, and may be as small as 1mm in the light. The visual system in the human brain is too slow to process information if images are slipping across the retina at more than a few degrees per second. Thus, to be able to see while moving, the brain must compensate for the motion of

3612-462: The eye are controlled by six muscles attached to each eye, and allow the eye to elevate, depress, converge, diverge and roll. These muscles are both controlled voluntarily and involuntarily to track objects and correct for simultaneous head movements. Rapid eye movement, REM, typically refers to the sleep stage during which the most vivid dreams occur. During this stage, the eyes move rapidly. Saccades are quick, simultaneous movements of both eyes in

3696-404: The eye are filled with the aqueous humour anteriorly, between the cornea and lens, and the vitreous body , a jelly-like substance, behind the lens, filling the entire posterior cavity. The aqueous humour is a clear watery fluid that is contained in two areas: the anterior chamber between the cornea and the iris, and the posterior chamber between the iris and the lens. The lens is suspended to

3780-404: The eye at up to 100°/s in adult humans. It is more difficult to visually estimate speed in low light conditions or while moving, unless there is another point of reference for determining speed. The optokinetic reflex (or optokinetic nystagmus) stabilizes the image on the retina through visual feedback. It is induced when the entire visual scene drifts across the retina, eliciting eye rotation in

3864-436: The eye is made up of the whitish sclera , a coloured iris , and the pupil . A thin layer called the conjunctiva sits on top of this. The front part is also called the anterior segment of the eye. The eye is not shaped like a perfect sphere; rather it is a fused two-piece unit, composed of an anterior (front) segment and the posterior (back) segment. The anterior segment is made up of the cornea, iris and lens. The cornea

3948-434: The final image. However, there are other algorithms that can remove false colors after demosaicing. These have the benefit of removing false coloring artifacts from the image while using a more robust demosaicing algorithm for interpolating the red and blue color planes. The zippering artifact is another side effect of CFA demosaicing, which also occurs primarily along edges, is known as the zipper effect. Simply put, zippering

4032-453: The front and rear makes the camera "nearly twice as rigid as ordinary cameras". Besides controlling zoom, the zoom ring is also used to power on the camera. Imaging-Resource noted that "the zoom lens obscures the lower right quadrant of the optical viewfinder", from about 45mm equivalent focal length to 28mm wide angle. Additionally, the user's index finger may appear in the viewfinder while zooming. In spite of this, Imaging-Resource expressed

4116-539: The green photosensors luminance-sensitive elements and the red and blue ones chrominance-sensitive elements . He used twice as many green elements as red or blue to mimic the physiology of the human eye . The luminance perception of the human retina uses M and L cone cells combined, during daylight vision, which are most sensitive to green light. These elements are referred to as sensor elements , sensels , pixel sensors , or simply pixels ; sample values sensed by them, after interpolation, become image pixels . At

4200-422: The head by turning the eyes. Frontal-eyed animals have a small area of the retina with very high visual acuity, the fovea centralis . It covers about 2 degrees of visual angle in people. To get a clear view of the world, the brain must turn the eyes so that the image of the object of regard falls on the fovea. Any failure to make eye movements correctly can lead to serious visual degradation. Having two eyes allows

4284-518: The image content and starting from this attempt to calculate the missing color values. Images with small-scale detail close to the resolution limit of the digital sensor can be a problem to the demosaicing algorithm, producing a result which does not look like the model. The most frequent artifact is Moiré , which may appear as repeating patterns, color artifacts or pixels arranged in an unrealistic maze-like pattern. A common and unfortunate artifact of Color Filter Array (CFA) interpolation or demosaicing

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4368-457: The image. However, even with a theoretically perfect sensor that could capture and distinguish all colors at each photosite, Moiré and other artifacts could still appear. This is an unavoidable consequence of any system that samples an otherwise continuous signal at discrete intervals or locations. For this reason, most photographic digital sensors incorporate something called an optical low-pass filter (OLPF) or an anti-aliasing (AA) filter . This

4452-438: The incidence of false colors, by having red, blue and green pixels in each line. The arrangement of these pixels is also said to provide grain more like film. One of main drawbacks for custom patterns is that they may lack full support in third party raw processing software like Adobe Photoshop Lightroom where adding improvements took multiple years. Sony introduced Quad Bayer color filter array, which first featured in

4536-599: The iris. Eye irritation has been defined as "the magnitude of any stinging, scratching, burning, or other irritating sensation from the eye". It is a common problem experienced by people of all ages. Related eye symptoms and signs of irritation are discomfort, dryness, excess tearing, itchiness, grating, foreign body sensation, ocular fatigue, pain, soreness, redness, swollen eyelids, and tiredness, etc. These eye symptoms are reported with intensities from mild to severe. It has been suggested that these eye symptoms are related to different causal mechanisms, and symptoms are related to

4620-444: The light that is reflected from the epithelium undergoes Mie scattering (which is not strongly frequency-dependent) rather than Rayleigh scattering (in which shorter wavelengths of light are scattered more). This would be analogous to the change in the color of the sky, from the blue given by the Rayleigh scattering of sunlight by small gas molecules when the sky is clear, to the gray caused by Mie scattering of large water droplets when

4704-423: The light-sensitive cells of the retina ( photoreceptor cones and rods ) are converted into electrical signals that are transmitted to the brain by the optic nerve and interpreted as sight and vision. The size of the eye differs among adults by only one or 2 millimetres. The eyeball is generally less tall than it is wide. The sagittal vertical (height) of a human adult eye is approximately 23.7 mm (0.93 in),

4788-421: The limbus connects the cornea and sclera. The iris is the pigmented circular structure concentrically surrounding the centre of the eye, the pupil, which appears to be black. The size of the pupil, which controls the amount of light entering the eye, is adjusted by the iris' dilator and sphincter muscles . Light energy enters the eye through the cornea, through the pupil and then through the lens. The lens shape

4872-471: The midday sun (10 cd/m ) or lightning discharge. At the low end of the range is the absolute threshold of vision for a steady light across a wide field of view, about 10 cd/m (0.000001 candela per square meter). The upper end of the range is given in terms of normal visual performance as 10 cd/m (100,000,000 or one hundred million candelas per square meter). The eye includes a lens similar to lenses found in optical instruments such as cameras and

4956-410: The outermost, white part of the eye (the sclera ) and one of its inner layers (the pigmented choroid ) keeping the eye essentially light tight except on the eye's optic axis . In order, along the optic axis, the optical components consist of a first lens (the cornea—the clear part of the eye ) that accounts for most of the optical power of the eye and accomplishes most of the focusing of light from

5040-406: The outside world; then an aperture (the pupil ) in a diaphragm (the iris—the coloured part of the eye ) that controls the amount of light entering the interior of the eye; then another lens (the crystalline lens ) that accomplishes the remaining focusing of light into images ; and finally a light-sensitive part of the eye (the retina ), where the images fall and are processed. The retina makes

5124-417: The particular ocular anatomy involved. Several suspected causal factors in our environment have been studied so far. One hypothesis is that indoor air pollution may cause eye and airway irritation. Eye irritation depends somewhat on destabilization of the outer-eye tear film, i.e. the formation of dry spots on the cornea, resulting in ocular discomfort. Occupational factors are also likely to influence

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5208-957: The perception of eye irritation. Some of these are lighting (glare and poor contrast), gaze position, reduced blink rate, limited number of breaks from visual tasking, and a constant combination of accommodation, musculoskeletal burden, and impairment of the visual nervous system. Another factor that may be related is work stress. In addition, psychological factors have been found in multivariate analyses to be associated with an increase in eye irritation among VDU users. Other risk factors, such as chemical toxins/irritants (e.g. amines , formaldehyde , acetaldehyde , acrolein , N-Decane , VOCs , ozone , pesticides and preservatives , allergens , etc.) might cause eye irritation as well. Certain volatile organic compounds that are both chemically reactive and airway irritants may cause eye irritation. Personal factors (e.g. use of contact lenses, eye make-up, and certain medications) may also affect destabilization of

5292-475: The prevalence of blue eye color among the white population in the United States to be 33.8% for those born from 1936 through 1951. Like blue eyes, gray eyes have a dark epithelium at the back of the iris and a relatively clear stroma at the front. One possible explanation for the difference in the appearance of gray and blue eyes is that gray eyes have larger deposits of collagen in the stroma, so that

5376-496: The recently discovered photosensitive ganglion cells respond to a full range of light intensities and contribute to adjusting the amount of light reaching the retina, to regulating and suppressing the hormone melatonin , and to entraining circadian rhythm . Humans have two eyes, situated on the left and the right of the face . The eyes sit in bony cavities called the orbits , in the skull . There are six extraocular muscles that control eye movements. The front visible part of

5460-481: The region. Amber eyes are a solid color with a strong yellowish/golden and russet/coppery tint, which may be due to the yellow pigment called lipochrome (also found in green eyes). Amber eyes should not be confused with hazel eyes. Although hazel eyes may contain specks of amber or gold, they usually tend to have many other colors, including green, brown and orange. Also, hazel eyes may appear to shift in color and consist of flecks and ripples, while amber eyes are of

5544-542: The replacement to successfully address the problem, and Fujifilm reported that complaints quickly diminished after the free replacement program was launched. SENSOR : EXR CMOS | Bayer CMOS | X-Trans | X-Trans II | X-Trans III | X-Trans 4 | X-Trans 5 VIDEO: 15 4K 15p , 4K , 6K , 8K   ⋅   SCREEN : Flip , Articulating , Touchscreen   ⋅   BODY FEATURE: In-Body Image Stabilization , Weather Sealed EXR color filter array A Bayer filter mosaic

5628-455: The retina in both eyes. To look at a nearby object, the eyes rotate 'towards each other' ( convergence ), while for an object farther away they rotate 'away from each other' ( divergence ). Lenses cannot refract light rays at their edges as well as closer to the centre. The image produced by any lens is therefore somewhat blurry around the edges ( spherical aberration ). It can be minimized by screening out peripheral light rays and looking only at

5712-655: The retina, allowing closer objects to be brought into better focus. The human eye contains enough complexity to warrant specialized attention and care beyond the duties of a general practitioner . These specialists, or eye care professionals , serve different functions in different countries. Eye care professionals can have overlap in their patient care privileges. For example, both an ophthalmologist (M.D.) and optometrist (O.D.) are professionals who diagnose eye disease and can prescribe lenses to correct vision. Typically, only ophthalmologists are licensed to perform surgical procedures. Ophthalmologists may also specialize within

5796-449: The right and left, all of which give input to the ocular muscles to maintain visual stability. Eyes can also follow a moving object around. This tracking is less accurate than the vestibulo-ocular reflex, as it requires the brain to process incoming visual information and supply feedback . Following an object moving at constant speed is relatively easy, though the eyes will often make saccades to keep up. The smooth pursuit movement can move

5880-417: The same color, the 6x6 pattern features 9x blue, 9x red, and 18x green. Human eye The human eye is a sensory organ in the visual system that reacts to visible light allowing eyesight . Other functions include maintaining the circadian rhythm , and keeping balance . The eye can be considered as a living optical device . It is approximately spherical in shape, with its outer layers, such as

5964-427: The same color. The main reason for this type of array is to contribute to pixel "binning", where two adjacent photosites can be merged, making the sensor itself more "sensitive" to light. Another reason is for the sensor to record two different exposures, which is then merged to produce an image with greater dynamic range. The underlying circuitry has two read-out channels that take their information from alternate rows of

6048-407: The same direction and at a velocity that minimizes the motion of the image on the retina. When the gaze direction deviates too far from the forward heading, a compensatory saccade is induced to reset the gaze to the centre of the visual field. For example, when looking out of the window at a moving train, the eyes can focus on a moving train for a short moment (by stabilizing it on the retina), until

6132-421: The same direction controlled by the frontal lobe of the brain. Even when looking intently at a single spot, the eyes drift around. This ensures that individual photosensitive cells are continually stimulated in different degrees. Without changing input, these cells would otherwise stop generating output. Eye movements include drift, ocular tremor , and microsaccades. Some irregular drifts, movements smaller than

6216-447: The same physics principles can be applied. The pupil of the human eye is its aperture ; the iris is the diaphragm that serves as the aperture stop. Refraction in the cornea causes the effective aperture (the entrance pupil ) to differ slightly from the physical pupil diameter. The entrance pupil is typically about 4 mm in diameter, although it can range from 2 mm ( f /8.3 ) in a brightly lit place to 8 mm ( f /2.1 ) in

6300-444: The sensor. They present several patterns, but none with a repeating unit as small as the Bayer pattern's 2×2 unit. Another 2007 U.S. patent filing, by Edward T. Chang, claims a sensor where "the color filter has a pattern comprising 2×2 blocks of pixels composed of one red, one blue, one green and one transparent pixel," in a configuration intended to include infrared sensitivity for higher overall sensitivity. The Kodak patent filing

6384-417: The sensor. The result is that it can act like two interleaved sensors, with different exposure times for each half of the photosites. Half of the photosites can be intentionally underexposed so that they fully capture the brighter areas of the scene. This retained highlight information can then be blended in with the output from the other half of the sensor that is recording a 'full' exposure, again making use of

6468-614: The sky is cloudy. Alternatively, it has been suggested that gray and blue eyes might differ in the concentration of melanin at the front of the stroma. Gray eyes can also be found among the Algerian Shawia people of the Aurès Mountains in Northwest Africa, in the Middle East / West Asia , Central Asia , and South Asia . Under magnification, gray eyes exhibit small amounts of yellow and brown color in

6552-462: The surrounding pixels of the corresponding colors to estimate the values for a particular pixel. Different algorithms requiring various amounts of computing power result in varying-quality final images. This can be done in-camera, producing a JPEG or TIFF image, or outside the camera using the raw data directly from the sensor. Since the processing power of the camera processor is limited, many photographers prefer to do these operations manually on

6636-403: The time Bayer registered his patent, he also proposed to use a cyan-magenta-yellow combination, that is another set of opposite colors. This arrangement was impractical at the time because the necessary dyes did not exist, but is used in some new digital cameras. The big advantage of the new CMY dyes is that they have an improved light absorption characteristic; that is, their quantum efficiency

6720-400: The train moves out of the field of vision. At this point, the eye is moved back to the point where it first saw the train (through a saccade). The adjustment to close-range vision involves three processes to focus an image on the retina. When a creature with binocular vision looks at an object, the eyes must rotate around a vertical axis so that the projection of the image is in the centre of

6804-425: The transverse horizontal diameter (width) is 24.2 mm (0.95 in) and the axial anteroposterior size (depth) averages 22.0–24.8 mm (0.87–0.98 in) with no significant difference between sexes and age groups. Strong correlation has been found between the transverse diameter and the width of the orbit (r = 0.88). The typical adult eye has an anterior to posterior diameter of 24 mm (0.94 in), and

6888-683: The world, it is nearly the only iris color present. Brown eyes are common in Europe , East Asia , Southeast Asia , Central Asia , South Asia , West Asia , Oceania , Africa and the Americas . Light or medium-pigmented brown eyes can also be commonly found in Europe , among the Americas , and parts of Central Asia , West Asia and South Asia . Light brown eyes bordering amber and hazel coloration are common in Europe, but can also be observed in East Asia and Southeast Asia, though are uncommon in

6972-517: Was described as "impressively bright". The X10 was the first of a new line of compact cameras from Fujifilm, with the letter X and two digits in the product name. Its immediate successor was the Fujifilm X20 in January 2013. The X10 has magnesium alloy top and bottom plates, and a mechanical zoom ring. According to Fujifilm, the fact that 1mm rather than 0.8mm aluminium sheets were chosen for

7056-519: Was earlier. Such cells have previously been used in " CMYW " (cyan, magenta, yellow, and white) "RGBW" (red, green, blue, white) sensors, but Kodak has not compared the new filter pattern to them yet. Fujifilm's EXR color filter array are manufactured in both CCD ( SuperCCD ) and CMOS (BSI CMOS). As with the SuperCCD, the filter itself is rotated 45 degrees. Unlike conventional Bayer filter designs, there are always two adjacent photosites detecting

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