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19-458: The Fujifilm X-Trans CMOS sensor used in the X-Pro1 (and other Fuji X-series cameras) is claimed to provide higher resolution than full-frame sensors, and also produce better colour reproduction. Anti-aliasing filters are used on standard Bayer Array Sensors to reduce moiré effect when shooting regular patterns - however they are known to slightly reduce resolution. The "X-Trans" CMOS sensor uses

38-433: A band-pass filter can be used as an anti-aliasing filter. For example, this could be done with a single-sideband modulated or frequency modulated signal. If one desired to sample an FM radio broadcast centered at 87.9 MHz and bandlimited to a 200 kHz band, then an appropriate anti-alias filter would be centered on 87.9 MHz with 200 kHz bandwidth (or passband of 87.8 MHz to 88.0 MHz), and

57-560: A different pattern of pixels in order to reduce moiré without the need for an AA filter . This same pattern ensures that all horizontal and vertical lines of pixels contain R, G and B pixels whereas Bayer array sensors do not have R and B in some lines. Fujifilm's Hybrid Viewfinder allows photographers to choose between an optical finder (OVF) and a high-resolution electronic view (EVF), complete with previews of depth of field and white balance. It also allows different optical magnifications and frame sizes to allow accurate framing with any of

76-425: A higher rate to reduce the requirements and distortion of the anti-alias filter. For example, compare CD audio with high-resolution audio . CD audio filters the signal to a passband edge of 20 kHz, with a stopband Nyquist frequency of 22.05 kHz and sample rate of 44.1 kHz. The narrow 2.05 kHz transition band requires a compromise between filter complexity and performance. High-resolution audio uses

95-620: A higher sample rate, providing both a higher passband edge and larger transition band, which allows better filter performance with reduced aliasing, reduced attenuation of higher audio frequencies and reduced time and phase domain signal distortion. Often, an anti-aliasing filter is a low-pass filter ; this is not a requirement, however. Generalizations of the Nyquist–Shannon sampling theorem allow sampling of other band-limited passband signals instead of baseband signals. For signals that are bandwidth limited, but not centered at zero,

114-453: A practice called oversampling . In the case of optical image sampling, as by image sensors in digital cameras , the anti-aliasing filter is also known as an optical low-pass filter ( OLPF ), blur filter , or AA filter . The mathematics of sampling in two spatial dimensions is similar to the mathematics of time-domain sampling, but the filter implementation technologies are different. The typical implementation in digital cameras

133-467: A trade off between reduced bandwidth and increased aliasing . A practical anti-aliasing filter will typically permit some aliasing to occur or attenuate or otherwise distort some in-band frequencies close to the Nyquist limit. For this reason, many practical systems sample higher than would be theoretically required by a perfect AAF in order to ensure that all frequencies of interest can be reconstructed,

152-529: Is a filter used before a signal sampler to restrict the bandwidth of a signal to satisfy the Nyquist–Shannon sampling theorem over the band of interest . Since the theorem states that unambiguous reconstruction of the signal from its samples is possible when the power of frequencies above the Nyquist frequency is zero, a brick wall filter is an idealized but impractical AAF. A practical AAF makes

171-417: Is two layers of birefringent material such as lithium niobate , which spreads each optical point into a cluster of four points. The choice of spot separation for such a filter involves a tradeoff among sharpness, aliasing, and fill factor (the ratio of the active refracting area of a microlens array to the total contiguous area occupied by the array). In a monochrome or three-CCD or Foveon X3 camera,

190-476: The passband of the anti-aliasing filter; these components can then alias, causing the reproduction of other non- harmonically related frequencies. Time-domain Time domain refers to the analysis of mathematical functions , physical signals or time series of economic or environmental data, with respect to time . In the time domain, the signal or function's value is known for all real numbers , for

209-554: The XF-mount lenses in the system. When an XF lens is mounted on the camera body, the most appropriate of the two available viewfinder magnifications is combined with the correct frame size. A number of reviews by popular photography websites have been very positive - with some noticeable negatives identified with the camera. The camera's high ISO performance is often cited as a strength, while reviews initially called out poor auto focus performance in low light and battery life as two of

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228-517: The camera's autofocus accuracy and speed, as well as new features such as focus peaking in the 3.0 firmware update. 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 Anti-aliasing filter An anti-aliasing filter ( AAF )

247-432: The case of continuous time , or at various separate instants in the case of discrete time . An oscilloscope is a tool commonly used to visualize real-world signals in the time domain. A time-domain graph shows how a signal changes with time, whereas a frequency-domain graph shows how much of the signal lies within each given frequency band over a range of frequencies. Though most precisely referring to time in physics ,

266-434: The input of an analog-to-digital converter . Similar filters are used as reconstruction filters at the output of a digital-to-analog converter . In the latter case, the filter prevents imaging, the reverse process of aliasing where in-band frequencies are mirrored out of band. With oversampling , a higher intermediate digital sample rate is used, so that a nearly ideal digital filter can sharply cut off aliasing near

285-423: The main weaknesses. Since its release, several firmware upgrades have been released that have significantly improved autofocus speed. Fuji has adopted a "Kaizen" approach, meaning continual updates and innovation in releasing firmware updates to the X-Pro1. Since the launch of the camera, there have been 21 firmware updates to fix bugs, improve the camera's performance and add new features. Key areas improved include

304-478: The microlens array alone, if near 100% effective, can provide a significant anti-aliasing function, while in color filter array (e.g. Bayer filter ) cameras, an additional filter is generally needed to reduce aliasing to an acceptable level. Alternative implementations include the Pentax K-3 's anti-aliasing filter, which applies small vibrations to the sensor element. Anti-aliasing filters are used at

323-496: The original low Nyquist frequency and give better phase response , while a much simpler analog filter can stop frequencies above the new higher Nyquist frequency. Because analog filters have relatively high cost and limited performance, relaxing the demands on the analog filter can greatly reduce both aliasing and cost. Furthermore, because some noise is averaged out, the higher sampling rate can moderately improve signal-to-noise ratio . A signal may be intentionally sampled at

342-431: The sampling rate would be no less than 400 kHz, but should also satisfy other constraints to prevent aliasing . It is very important to avoid input signal overload when using an anti-aliasing filter. If the signal is strong enough, it can cause clipping at the analog-to-digital converter , even after filtering. When distortion due to clipping occurs after the anti-aliasing filter, it can create components outside

361-407: The term time domain may occasionally informally refer to position in space when dealing with spatial frequencies , as a substitute for the more precise term spatial domain . The use of the contrasting terms time domain and frequency domain developed in U.S. communication engineering in the late 1940s, with the terms appearing together without definition by 1950. When an analysis uses

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