Is WV511 Camera Right For You? Expert Review Inside ... - vl2l determine camera sensor

 2024-09-05 10:23:46

Enter your telescope and imaging parameters using the sliders and/or numeric entry fields. Telescope parameters can either be entered as aperture and focal ratio, or focal length and focal ratio, by selecting the input mode. Telescopes are normally specified by aperture and focal ratio, while camera lenses are normally specified by focal length and focal ratio. The third parameter, focal length or aperture, will be computed automatically. In Aperture & Focal Ratio mode, for example, the focal length will be calculated automatically by multiplying the aperture by the focal ratio. For focal ratio, be sure to enter the final focal ratio of your system, including any reducers or extenders in use.

Here are TAMRON's recommended lenses by lens type. TAMRON zoom lenses cover a wide range of focal lengths with a single lens yet are of a size that makes them easy to carry. On top of this, they are characterized by their high descriptive performance and close-up shooting ability. We hope you will find the lens that suits you best.

The focal length of a lens is defined as the distance from the center of the lens (principal point) to the image sensor of the camera. Focal length is an important figure that determines the angle of view. A lens with a short focal length is a wide-angle lens, a lens with a long focal length is a telephoto lens and a standard lens is somewhere in between. When choosing a lens, pay attention to the focal length and select a lens that suits the subject or scene you want to photograph.

Wide-angle zoom lenses cover the range from ultra wide-angle to standard range. Ultra wide-angle lenses allow you to get closer to buildings and vehicles and still capture a wide range of subjects, resulting in more dynamic shots. It also allows for unique portrait and pet photography, making the most of the perspective. Lightweight and compact TAMRON lenses are particularly useful when shooting landscapes, as the time and distance spent carrying them around can be long.

Another characteristic of focal length is depth of field. Depth of field refers to the range in which the image looks it is in focus, and a deep depth of field means that the image looks in focus through wide range, such as from a subject to background. And if the depth of field is shallow, only the area around the subject will be in focus and the background will have a smooth bokeh. The shorter the focal length of the lens and the larger the aperture (F-number), the deeper the depth of field. This is why wide-angle lenses are suitable for landscape photography, as the short focal length increases the depth of field and allows the photographer to capture details in the background clearly. On the other hand, as telephoto lenses have a long focal length and shallow depth of field, the bokeh in the background of a subject is more pronounced. By utilizing these bokeh effects, you can capture portraits and other images where the subject stands out against the background.

Telephoto zoom lenses enable photographers bring the subject closer, making them ideal for events such as sports events, as well as for birding and wildlife. They are also useful in natural landscapes photographed in conjunction with trekking, hiking and mountaineering.They are also recommended for impressive portrait photography with naturally blurred backgrounds and compression effects.

You will notice that with certain input parameters, a portion of the overall MTF plot will turn red. This indicates the range of spatial frequencies over which undersampling is occurring. Undersampling happens when the camera’s pixels are too large to capture fine-scale (high spatial frequency) detail that could otherwise be captured with smaller pixels. By moving the Seeing and/or Pixel Size sliders, you can experiment and see what it would take to properly sample the image produced by your optical setup. At very short focal lengths, it is nearly impossible to avoid undersampling.

The 35-150mm F/2-2.8 Di III VXD (Model A058) is a high resolution travel zoom lens that covers everything from the 35mm wide angle to the 150mm telephoto focal length, the first zoom lens achieving an aperture of F2 at the wide angle end. It has a groundbreaking fast-aperture and utilizes the linear motor focus mechanism VXD (Voice-coil eXtreme-torque Drive), thereby achieving high speed, high precision autofocusing. The innovative lens design enabled us to greatly improve the lens's grip and functionality. The software, developed in-house, enables to easily customize functions and to update firmware.

The 17-70mm F/2.8 Di III-A VC RXD (Model B070) is a large-aperture standard zoom lens for APS-C format mirrorless cameras. With a focal length range of 17mm to 70mm (a full-frame equivalent of 25.5-105mm) for daily use, this achieves a 4.1x zoom. The optical design ensures high resolution and high contrast not just in the center of the image but also in corners and at the edges. The quiet AF drive motor and the VC image stabilization mechanism facilitate hand-held shooting. In addition, by counteracting focus breathing, the 17-70mm F2.8 empowers users' expression of their creative intentions to the fullest degree. This highly practical lens allows you to easily enjoy the high image quality of a large F2.8 aperture for both still and video shooting.

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The 150-500mm F/5-6.7 Di III VC VXD (Model A057) is compact enough to be handheld while maintaining a focal length of 500mm on the telephoto end. It allows users to easily enjoy the world of the 500mm ultra-telephoto lens while maintaining its high image quality. The high-speed, high-precision AF with excellent tracking performance and the VC mechanism support handheld shooting in the ultra-telephoto range.

As explained above, focal length is a very important figure, but when choosing a lens you also need to be mindful of the sensor size on your camera body. With digital SLR cameras, light reaching the image sensor is stored as an electrical charge, and an image is created based on the color information obtained through the color filter. These image sensors come in mainly two types: 35mm full-frame, and APS-C. The size of a 35mm full-frame sensor is 36mm x 24mm. The larger the sensor size allows a wider area to be captured with greater sensitivity and its rich gradation. On the other hand, the size of an APS-C sensor is a step smaller at 23.5mm x 15.6mm* and captures narrower area. *APS-C image sensor sizes vary by camera. Therefore, you will need a lens that is compatible with the sensor size of the camera body. Camera lenses have a specific sensor size that they are compatible with, so choose a lens that is compatible with the camera you have. When APS-C camera is used, you will need to do some calculation to figure out the real coverage. The angle of view of each focal length depends on the sensor size. Generally, focal lengths and angles of view are based on 35mm full-frame size, so when selecting an APS-C compatible lens, it is easier to understand the angle of view when converted to full-frame size. Such conversion is known as '35mm equivalent'. In general, the focal length of APS-C lenses can be converted to the focal length of lenses for full-frame cameras by multiplying the focal length by 1.5 (for Sony, Nikon and 1.6 for Canon). The relationship between angle of view and focal length can be mapped as shown in the table below, which you can use as a reference when selecting a lens for APS-C.

The Modulation Transfer Function (MTF) is a depiction of how much contrast is lost versus spatial frequency for a given system. A graph of the MTF always starts at 1.0 (100% contrast reproduction) at a spatial frequency of zero, which is basically saying that light passes through the instrument. As the spatial frequency increases, and signficant details become more closely spaced, the optics have more and more difficulty reproducing those variations in light intensity. Contrast drops until finally reaching zero, meaning no detail is preserved at or above that scale.

The 20-40mm F/2.8 Di III VXD (Model A062) is a new large-aperture standard zoom lens that thoroughly pursues portability. While covering the range from the ultra-wide angle of 20mm to the standard range of 40mm, it is the smallest and lightest in its class. It also offers high image quality throughout the entire zoom range, making it useful not only for still image shooting but also for video recording such as vlogging. The VXD, which is quiet and agile, achieves high-speed, high-precision autofocusing. It is a new, unprecedented large-aperture standard zoom lens that allows users to easily enjoy taking out and shooting both still and video.

The opposite of undersampling is oversampling, which is to say that the camera’s pixels are so small relative to the features projected onto the sensor by the optics that more than enough pixels are capturing the available detail. There is nothing wrong with oversampling: no detail is being lost as it is with undersampling. It does, however, result in image file sizes that are larger than necessary, and some image processing tools are not designed to handle excessive amounts of oversampling. While it is better to be slightly oversampled than slightly undersampled, if that choice exists, excessively oversampled images can safely be “down-sampled” or “binned” in software or hardware. A Total FWHM value above 8 pixels is excessively oversampled. With older CCD cameras, binning in the camera during image readout actually improves the signal-to-noise ratio of the image, but with most modern CMOS cameras, binning or “integer resampling” can be done in software.

Spatial frequency is an important concept in understanding the detail present in an image. It is basically a measure of how rapidly the intensity of light changes over distance across the camera sensor or, more relevant for our purposes, over angle on the sky. Large-scale variations, such as the overall change in brightness across the span of a nebula or galaxy, are represented by low spatial frequencies. Fine-scale details like stars, small structures in galaxies and nebulas, etc., are reprented by high spatial frequencies. It is the contrast at these high spatial frequencies which give an image its appearance of sharpness or clarity, and let us see all of the detail that makes astronomical objects so interesting.

The 50-400mm F/4.5-6.3 Di III VC VXD (Model A067) is an ultra-telephoto zoom lens with an 8x zoom starting at 50mm at the wide-angle end and compatible with full-frame mirrorless cameras. The lens delivers uncompromised high image quality over the entire 50-400mm focal length range, yet is as compact and lightweight as a 100-400mm class lens. Equipped with the VXD mechanism and the VC mechanism, the lens can quickly focus on the subject's movement when shooting sports and wild birds. The 50-400mm F4.5-6.3 is a new ultra-telephoto zoom lens that combines unparalleled image quality and mobility.

When light enters a lens, the point where the light gathers is called the focal point. While light travels in a straight ray, when it passes through a lens it refracts and is concentrated at a single point so called focal point. When a light passes through a lens and at this focal point it forms an image, when an image sensor is placed at this position, the image can be captured. A focal length is a distance from the center of the lens (principal point) to the image sensor, and this is an important value that characterizes a lens.

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Note that the term “diffraction limit” is frequently used to mean two different things. One is the ultimate limit of angular resolution achievable by an instrument with a given aperture. The other meaning is related to this, but expresses the contrast loss as spatial frequency increases toward this ultimate limit. Both of these are expressed in the MTF graph. The Diffraction Limit curve represents the constrast loss across spatial frequency of a “perfect” optical system. The point on the far right at which this curve reaches zero is the ultimate diffraction limit — the highest spatial frequency or, in other words, the minimum angular separation that the system can resolve.

The important point about focal length is that the angle of view changes with its actual number. The angle of view is the angle of area captured by the camera through the lens, and the larger the angel of view, the wider the area is captured. Lens types can be roughly divided into three categories: wide-angle, standard, and telephoto. A standard lens can capture images at an angle of view close to that of the human field of view. Generally, lenses with a wider angle of view are called wide-angle lenses, and lenses with a narrower angle of view are called telephoto lenses. As a general rule of thumb for focal lengths, focal length smaller than 35mm are generally classified into wide-angle lens, lenses around 50mm are called standard lens, and lenses larger than 80mm are telephoto lens. Check out the differences in impression and composition caused by changing the angle of view. Here is an example of a portrait taken with the TAMRON 35-150mm F/2-2.8 Di III VXD (Model A058) at a different focal length. At the wide-angle end (35 mm), the beautiful impression of the figure standing stands out with the background. At the telephoto end (150 mm), on the other hand, the expression on the person's face is compelling and the background bokeh accentuates this image. In this way, by changing the focal length of a zoom lens, various angles of view can be created, and different impressions can be captured.

11-20mm F/2.8 Di III-A RXD (Model B060) is the world's first compact, lightweight F2.8 ultra wide-angle zoom lens for Sony E-mount APS-C mirrorless cameras. Can be a great choice for video shooting.

A fundamental factor that limits the achievable resolution for any optical system, imposed by the wave nature of light iself, is the diffraction limit. An image of tiny spot of light (such as a star) produced by an optical system will never be smaller than a certain size on the camera, no matter how perfect the optics, due to how light behaves. Thinking of the physical size of this spot on the camera sensor, the only thing that can make it smaller is reducing the focal ratio of the optics. Thinking instead of what the size of this spot means in terms of capturing fine detail on the sky, the only thing that can improve this is inreasing the aperture of the instrument.

Modulation transfer functionimageprocessing

28-75mm F/2.8 Di III VXD G2 (Model A063) is the second-generation fast-aperture standard zoom lens for Sony and Nikon full-frame mirrorless cameras, offering significantly improved optical and autofocus performance and new function customization.

Here is some basic knowledge about focal length with interchangeable lenses that you will need to know when shooting with an SLR or mirrorless SLR camera. When shooting with an interchangeable lens camera, you can take beautiful and impressive photos by working with the angle of view, focus point and degree of bokeh. Particularly when choosing a lens, it is important to understand the characteristics of focal length as the angle of view changes depending on focal length. Let’s learn the basic knowledge and make use of it to take the photos as you imagine.

To designers of telescopes and lenses, the dashed Diffraction Limit curve represents perfection: if they do their job well, the performance of their designs will approach this curve across the entire field of view. A truly perfect optical system, however, one that faithfully reproduces contrast at all spatial frequencies, would be a straight line across the top of the graph: 100% contrast at all spatial frequencies. This is not fully achievable, of course, but can be approached with good optics, good seeing, good acquisition equipment and skills, sufficient exposure time, and modern deconvolution tools such as BlurXTerminator. Deconvolution restores contrast in an image, often raising it above the diffraction limit in the MTF curve, as if the image had been taken with a much larger instrument or under much better seeing conditions.

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As ultra-telephoto zoom lenses allow you to enlarge the faraway subjects, they are best suited for shooting subjects you cannot get close to, such as wildlife, sporting events held at large venues, aircraft and trains. By combining the compression effects and bokeh that telephoto zooms are known for, you can also compose more appealing images.

Generally, on a camera lens there is an indication of focal length. For a product name such as “28-75mm F/2.8, ” this “xx mm” indicates the focal length. There are two types of lenses: prime lenses which have a single focal length, and zoom lenses that have a variable focal length. If the focal length is described with a range, such as “xx-xx mm,” it is a zoom lens. For a prime lens, only a single figure is indicated, such as “xx mm.” Example of a zoom lens: 28-75mm F/2.8 Di III VXD G2 (Model A063)Example of a prime lens: 20mm F/2.8 Di III OSD M1:2 (Model F050)

Spatial frequency can be measured in two ways: in the image space, referring to the physical size of features in the image projected onto the camera sensor, or in the object space, referring to angular distances on the sky. The latter is more useful and intuitive for our purposes here, and is measured in units of cycles per arcsecond. A cycle is an alternation in an image feature from bright to dark. The more rapidly light varies versus angle on the sky in a particular part of an image, the higher the spatial frequency.

Undersampling is not necessarily a disaster: it simply means that there is finer resolution available from your optics and imaging conditions than can be captured by your camera. Often a sacrifice is being made: the field of view is wider at shorter focal lengths, allowing large objects to be imaged in a single frame, but the ability of the camera to capture the finest details is lost.

The 17-28mm F/2.8 Di III RXD (Model A046) achieves a filter diameter of ø67mm, which is surprising for a large aperture ultra wide-angle zoom lens for full-frame cameras. It’s small and light weight with a good camera balance. It's a dedicated lens for mirrorless interchangeable -lens cameras that can be carried easily and can be used in various situations.

Product Page | 11-20mm F/2.8 Di III-A RXD (Model B060) is the world's first compact, lightweight F2.8 ultra wide-angle zoom lens for Sony E-mount APS-C mirrorless cameras. Can be a great choice for video shooting.

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If you want to evaluate whether or not this is appropriate for your system, click the “Bin 2×2” mode above. If no portion of the overall MTF curve turns red, then binning or integer resampling can be done with no loss of detail. Your image processing will run about four times faster, you’ll use four times less disk space to store your images, and image processing alorithm developers will be pleased.

In addition to the focal length, the F-number (aperture value) is another important figure that expresses the characteristics of the lens: the smaller the F-number, the more light-gathering power it will have, and will broaden your possibility. The F-number is calculated as 'focal length ÷ lens effective diameter'. The smaller the 'maximum aperture F value' when the aperture is at its widest, the more sensitive the lens is. When choosing a lens, it is better to mind the F-number as well as the focal length.

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70-180mm F/2.8 Di III VC VXD G2 (Model A065) has evolved to G2 level.This is the world’s smallest and lightest, fast-aperture telephoto zoom lens for Sony E-mount with astounding portability and superb image quality.

A standard zoom lens covers wide-angle to telephoto focal lengths around 50mm. In addition to snap shots and portraits, these lenses prove their worth in a wide variety of shooting scenarios such as landscapes at the wide end and shots of animals and buildings at the telephoto end.

Enter your imaging site’s typical seeing, the imaging wavelength of interest, and your camera’s native pixel size. You can also select one of the drizzle or binning modes if you intend to use these in your acquisition or processing workflow. Keep the Pixel Size parameter at the native pixel size: it will be multiplied or divided correctly when computing results if drizzle or binning is selected.

Anything less than 100% contrast represents blurred detail. This contrast, whether it has been lost by diffraction, seeing, or pixel sampling, can be at least partially restored by deconvolution.

Drizzle is a technique than can be used in many cases to recover some of this lost resolution. If your native camera resolution undersamples the image produced by your optics, as shown by the red part of the MTF curve, you can select a drizzle factor to see an approximation of how much more detail can be captured using this technique. Note that the recovered detail usually has very low contrast. Deconvolution can restore this contrast and fully realize the potential of the drizzle technique.

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The 17-50mm F/4 Di III VXD (Model A068)It's the world’s first lens covering from ultra wide-angle 17mm to the standard 50mm focal length. The highly-compact TAMRON 17-50mm F/4 Di III VXD (model a068) for Sony E-mount full-frame mirrorless cameras offers maximum versatility for still and video creators. From landscapes to living rooms, this lens captures all that you see.

The 70-300mm F/4.5-6.3 Di III RXD (Model A047) for full-frame mirrorless cameras is a telephoto zoom lens designed and created so photographers of all skill levels can enjoy high quality images comfortably. The 70-300mm F4.5-6.3 covers a broad telephoto zoom range yet is the small and lightest weight. With special emphasis on resolving power, TAMRON has deployed special lens elements appropriately arranged to correct chromatic aberration, generally very strong in a telephoto lens, as well as other aberrations. Users can enjoy high-resolution images combined with stunning bokeh qualities that are achievable only with a telephoto lens. The lens also incorporates the RXD, a high-speed precision AF drive system that is remarkably quiet. The 70-300mm F4.5-6.3 is a versatile lens for photographing landscapes, sports and other action, pets, wildlife, and more. The lens also demonstrates its potential for portrait shooting, casual snapshots, and scenarios that require you to be mobile and shoot handheld, like sporting events.

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The 50-400mm F/4.5-6.3 Di III VC VXD (Model A067) is an ultra-telephoto zoom lens with an 8x zoom starting at 50mm at the wide-angle end and compatible with full-frame mirrorless cameras. The lens delivers uncompromised high image quality over the entire 50-400mm focal length range, yet is as compact and lightweight as a 100-400mm class lens. Equipped with the VXD mechanism and the VC mechanism, the lens can quickly focus on the subject's movement when shooting sports and wild birds. The 50-400mm F4.5-6.3 VC is a new ultra-telephoto zoom lens that combines unparalleled image quality and mobility.

Using this information, key values such as the plate scale, stellar full-width at half maximum (FWHM), and the ultimate diffraction limit of your sytem will be computed, and the graph of your system’s Modulation Transfer Function will be updated. You can readily see whether diffraction, seeing, or the camera’s pixels are the main source of loss of contrast (blurring). Most imaging systems with a focal length greater than one meter, at typical imaging sites, are limited by seeing. At lower focal lengths, or at sites (or on nights) with excellent seeing, blurring by the camera’s pixels becomes a significant source of loss of contrast. In exceptional cases, the diffraction limit of the optics is dominant. By moving the sliders around and experimenting with various values of seeing, aperture, focal ratio, etc., you can become more familiar with how these parameters affect the achievable resolution, and which ones matter most in various scenarios.