The Basic Purpose of a Lens of Any Kind Is to Collect the Light Scattered by an Object and Recreate an Image of the Object on A
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“Digital Single Lens Reflex”
PHOTOGRAPHY GENERIC ELECTIVE SEM-II DSLR stands for “Digital Single Lens Reflex”. In simple language, a DSLR is a digital camera that uses a mirror mechanism to either reflect light from a camera lens to an optical viewfinder (which is an eyepiece on the back of the camera that one looks through to see what they are taking a picture of) or let light fully pass onto the image sensor (which captures the image) by moving the mirror out of the way. Although single lens reflex cameras have been available in various shapes and forms since the 19th century with film as the recording medium, the first commercial digital SLR with an image sensor appeared in 1991. Compared to point-and-shoot and phone cameras, DSLR cameras typically use interchangeable lenses. Take a look at the following image of an SLR cross section (image courtesy of Wikipedia): When you look through a DSLR viewfinder / eyepiece on the back of the camera, whatever you see is passed through the lens attached to the camera, which means that you could be looking at exactly what you are going to capture. Light from the scene you are attempting to capture passes through the lens into a reflex mirror (#2) that sits at a 45 degree angle inside the camera chamber, which then forwards the light vertically to an optical element called a “pentaprism” (#7). The pentaprism then converts the vertical light to horizontal by redirecting the light through two separate mirrors, right into the viewfinder (#8). When you take a picture, the reflex mirror (#2) swings upwards, blocking the vertical pathway and letting the light directly through. -
Panoramas Shoot with the Camera Positioned Vertically As This Will Give the Photo Merging Software More Wriggle-Room in Merging the Images
P a n o r a m a s What is a Panorama? A panoramic photo covers a larger field of view than a “normal” photograph. In general if the aspect ratio is 2 to 1 or greater then it’s classified as a panoramic photo. This sample is about 3 times wider than tall, an aspect ratio of 3 to 1. What is a Panorama? A panorama is not limited to horizontal shots only. Vertical images are also an option. How is a Panorama Made? Panoramic photos are created by taking a series of overlapping photos and merging them together using software. Why Not Just Crop a Photo? • Making a panorama by cropping deletes a lot of data from the image. • That’s not a problem if you are just going to view it in a small format or at a low resolution. • However, if you want to print the image in a large format the loss of data will limit the size and quality that can be made. Get a Really Wide Angle Lens? • A wide-angle lens still may not be wide enough to capture the whole scene in a single shot. Sometime you just can’t get back far enough. • Photos taken with a wide-angle lens can exhibit undesirable lens distortion. • Lens cost, an auto focus 14mm f/2.8 lens can set you back $1,800 plus. What Lens to Use? • A standard lens works very well for taking panoramic photos. • You get minimal lens distortion, resulting in more realistic panoramic photos. • Choose a lens or focal length on a zoom lens of between 35mm and 80mm. -
Photography and Photomontage in Landscape and Visual Impact Assessment
Photography and Photomontage in Landscape and Visual Impact Assessment Landscape Institute Technical Guidance Note Public ConsuDRAFTltation Draft 2018-06-01 To the recipient of this draft guidance The Landscape Institute is keen to hear the views of LI members and non-members alike. We are happy to receive your comments in any form (eg annotated PDF, email with paragraph references ) via email to [email protected] which will be forwarded to the Chair of the working group. Alternatively, members may make comments on Talking Landscape: Topic “Photography and Photomontage Update”. You may provide any comments you consider would be useful, but may wish to use the following as a guide. 1) Do you expect to be able to use this guidance? If not, why not? 2) Please identify anything you consider to be unclear, or needing further explanation or justification. 3) Please identify anything you disagree with and state why. 4) Could the information be better-organised? If so, how? 5) Are there any important points that should be added? 6) Is there anything in the guidance which is not required? 7) Is there any unnecessary duplication? 8) Any other suggeDRAFTstions? Responses to be returned by 29 June 2018. Incidentally, the ##’s are to aid a final check of cross-references before publication. Contents 1 Introduction Appendices 2 Background Methodology App 01 Site equipment 3 Photography App 02 Camera settings - equipment and approaches needed to capture App 03 Dealing with panoramas suitable images App 04 Technical methodology template -
Chapter 3 (Aberrations)
Chapter 3 Aberrations 3.1 Introduction In Chap. 2 we discussed the image-forming characteristics of optical systems, but we limited our consideration to an infinitesimal thread- like region about the optical axis called the paraxial region. In this chapter we will consider, in general terms, the behavior of lenses with finite apertures and fields of view. It has been pointed out that well- corrected optical systems behave nearly according to the rules of paraxial imagery given in Chap. 2. This is another way of stating that a lens without aberrations forms an image of the size and in the loca- tion given by the equations for the paraxial or first-order region. We shall measure the aberrations by the amount by which rays miss the paraxial image point. It can be seen that aberrations may be determined by calculating the location of the paraxial image of an object point and then tracing a large number of rays (by the exact trigonometrical ray-tracing equa- tions of Chap. 10) to determine the amounts by which the rays depart from the paraxial image point. Stated this baldly, the mathematical determination of the aberrations of a lens which covered any reason- able field at a real aperture would seem a formidable task, involving an almost infinite amount of labor. However, by classifying the various types of image faults and by understanding the behavior of each type, the work of determining the aberrations of a lens system can be sim- plified greatly, since only a few rays need be traced to evaluate each aberration; thus the problem assumes more manageable proportions. -
Do Something Important.TM
2.6X zoom in a cool, compact, capsule design with Advanced Photo System convenience. Do somethingwww.minolta.com important.TM www.minolta.com It’s All Within Your Grasp The VECTIS 260 makes picture-taking more fun for the whole family. The Advanced Photo System means easier operation and higher quality pictures, and a powerful 2.6X zoom expands your photo possibilities. Various automatic functions make it simple for everyone to take great pictures. It’s the compact camera that gives you more. ADVANCED PHOTO SYSTEM Get closer with 2.6X zoom! High-quality zoom lens adds variety to your photos. Powerful 2.6X Zoom A zoom lens this powerful gives you much greater versatility in framing your shots. You can take broad shots of the scenery, then zoom in for close-ups of the kids. The zoom range is a wide 25 — 65mm (equivalent to 31— 81mm in 35mm for- mat). For close-ups, you can move in as close as 1.64 ft. to your subject at any focal length, without having to set a special mode. Best of all, 25mm WIDE your photo will be sharp and clear, thanks to the Minolta high quality 4-element, 4-group zoom lens. 65mm TELE Greater ease and convenience Advanced Photo System makes photography more enjoyable — from start to finish! Index Prints for At-a-Glance Selection Drop-In Loading With photos this good, you’ll want to make reprints ... and now and Film Chamber Lock you can easily select the ones you want. With your pictures The ultimate in film loading you’ll receive an Index Print sheet, making it easy ease. -
Determination of Focal Length of a Converging Lens and Mirror
Physics 41- Lab 5 Determination of Focal Length of A Converging Lens and Mirror Objective: Apply the thin-lens equation and the mirror equation to determine the focal length of a converging (biconvex) lens and mirror. Apparatus: Biconvex glass lens, spherical concave mirror, meter ruler, optical bench, lens holder, self-illuminated object (generally a vertical arrow), screen. Background In class you have studied the physics of thin lenses and spherical mirrors. In today's lab, we will analyze several physical configurations using both biconvex lenses and concave mirrors. The components of the experiment, that is, the optics device (lens or mirror), object and image screen, will be placed on a meter stick and may be repositioned easily. The meter stick is used to determine the position of each component. For our object, we will make use of a light source with some distinguishing marking, such as an arrow or visible filament. Light from the object passes through the lens and the resulting image is focused onto a white screen. One characteristic feature of all thin lenses and concave mirrors is the focal length, f, and is defined as the image distance of an object that is positioned infinitely far way. The focal lengths of a biconvex lens and a concave mirror are shown in Figures 1 and 2, respectively. Notice the incoming light rays from the object are parallel, indicating the object is very far away. The point, C, in Figure 2 marks the center of curvature of the mirror. The distance from C to any point on the mirror is known as the radius of curvature, R. -
How Does the Light Adjustable Lens Work? What Should I Expect in The
How does the Light Adjustable Lens work? The unique feature of the Light Adjustable Lens is that the shape and focusing characteristics can be changed after implantation in the eye using an office-based UV light source called a Light Delivery Device or LDD. The Light Adjustable Lens itself has special particles (called macromers), which are distributed throughout the lens. When ultraviolet (UV) light from the LDD is directed to a specific area of the lens, the particles in the path of the light connect with other particles (forming polymers). The remaining unconnected particles then move to the exposed area. This movement causes a highly predictable change in the curvature of the lens. The new shape of the lens will match the prescription you selected during your eye exam. What should I expect in the period after cataract surgery? Please follow all instructions provided to you by your eye doctor and staff, including wearing of the UV-blocking glasses that will be provided to you. As with any cataract surgery, your vision may not be perfect after surgery. While your eye doctor selected the lens he or she anticipated would give you the best possible vision, it was only an estimate. Fortunately, you have selected the Light Adjustable Lens! In the next weeks, you and your eye doctor will work together to optimize your vision. Please make sure to pay close attention to your vision and be prepared to discuss preferences with your eye doctor. Why do I have to wear UV-blocking glasses? The UV-blocking glasses you are provided with protect the Light Adjustable Lens from UV light sources other than the LDD that your doctor will use to optimize your vision. -
Holographic Optics for Thin and Lightweight Virtual Reality
Holographic Optics for Thin and Lightweight Virtual Reality ANDREW MAIMONE, Facebook Reality Labs JUNREN WANG, Facebook Reality Labs Fig. 1. Left: Photo of full color holographic display in benchtop form factor. Center: Prototype VR display in sunglasses-like form factor with display thickness of 8.9 mm. Driving electronics and light sources are external. Right: Photo of content displayed on prototype in center image. Car scenes by komba/Shutterstock. We present a class of display designs combining holographic optics, direc- small text near the limit of human visual acuity. This use case also tional backlighting, laser illumination, and polarization-based optical folding brings VR out of the home and in to work and public spaces where to achieve thin, lightweight, and high performance near-eye displays for socially acceptable sunglasses and eyeglasses form factors prevail. virtual reality. Several design alternatives are proposed, compared, and ex- VR has made good progress in the past few years, and entirely perimentally validated as prototypes. Using only thin, flat films as optical self-contained head-worn systems are now commercially available. components, we demonstrate VR displays with thicknesses of less than 9 However, current headsets still have box-like form factors and pro- mm, fields of view of over 90◦ horizontally, and form factors approach- ing sunglasses. In a benchtop form factor, we also demonstrate a full color vide only a fraction of the resolution of the human eye. Emerging display using wavelength-multiplexed holographic lenses that uses laser optical design techniques, such as polarization-based optical folding, illumination to provide a large gamut and highly saturated color. -
Field of View - Wikipedia, the Free Encyclopedia
Field of view - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/Field_of_view From Wikipedia, the free encyclopedia The field of view (also field of vision, abbreviated FOV) is the extent of the observable world that is seen at any given moment. In case of optical instruments or sensors it is a solid angle through which a detector is sensitive to electromagnetic radiation. 1 Humans and animals 2 Conversions Horizontal Field of View 3 Machine vision 4 Remote sensing 5 Astronomy 6 Photography 7 Video games 8 See also 9 References In the context of human vision, the term “field of view” is typically used in the sense of a restriction Vertical Field of View to what is visible by external apparatus, like spectacles[2] or virtual reality goggles. Note that eye movements do not change the field of view. If the analogy of the eye’s retina working as a sensor is drawn upon, the corresponding concept in human (and much of animal vision) is the visual field. [3] It is defined as “the number of degrees of visual angle during stable fixation of the eyes”.[4]. Note that eye movements are excluded in the definition. Different animals have different visual fields, depending, among others, on the placement of the eyes. Humans have an almost 180-degree forward-facing horizontal diameter of their visual field, while some birds have a complete or nearly complete 360-degree Angle of view can be measured visual field. The vertical range of the visual field in humans is typically horizontally, vertically, or diagonally. -
Ground-Based Photographic Monitoring
United States Department of Agriculture Ground-Based Forest Service Pacific Northwest Research Station Photographic General Technical Report PNW-GTR-503 Monitoring May 2001 Frederick C. Hall Author Frederick C. Hall is senior plant ecologist, U.S. Department of Agriculture, Forest Service, Pacific Northwest Region, Natural Resources, P.O. Box 3623, Portland, Oregon 97208-3623. Paper prepared in cooperation with the Pacific Northwest Region. Abstract Hall, Frederick C. 2001 Ground-based photographic monitoring. Gen. Tech. Rep. PNW-GTR-503. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 340 p. Land management professionals (foresters, wildlife biologists, range managers, and land managers such as ranchers and forest land owners) often have need to evaluate their management activities. Photographic monitoring is a fast, simple, and effective way to determine if changes made to an area have been successful. Ground-based photo monitoring means using photographs taken at a specific site to monitor conditions or change. It may be divided into two systems: (1) comparison photos, whereby a photograph is used to compare a known condition with field conditions to estimate some parameter of the field condition; and (2) repeat photo- graphs, whereby several pictures are taken of the same tract of ground over time to detect change. Comparison systems deal with fuel loading, herbage utilization, and public reaction to scenery. Repeat photography is discussed in relation to land- scape, remote, and site-specific systems. Critical attributes of repeat photography are (1) maps to find the sampling location and of the photo monitoring layout; (2) documentation of the monitoring system to include purpose, camera and film, w e a t h e r, season, sampling technique, and equipment; and (3) precise replication of photographs. -
Depth of Field Lenses Form Images of Objects a Predictable Distance Away from the Lens. the Distance from the Image to the Lens Is the Image Distance
Depth of Field Lenses form images of objects a predictable distance away from the lens. The distance from the image to the lens is the image distance. Image distance depends on the object distance (distance from object to the lens) and the focal length of the lens. Figure 1 shows how the image distance depends on object distance for lenses with focal lengths of 35 mm and 200 mm. Figure 1: Dependence Of Image Distance Upon Object Distance Cameras use lenses to focus the images of object upon the film or exposure medium. Objects within a photographic Figure 2 scene are usually a varying distance from the lens. Because a lens is capable of precisely focusing objects of a single distance, some objects will be precisely focused while others will be out of focus and even blurred. Skilled photographers strive to maximize the depth of field within their photographs. Depth of field refers to the distance between the nearest and the farthest objects within a photographic scene that are acceptably focused. Figure 2 is an example of a photograph with a shallow depth of field. One variable that affects depth of field is the f-number. The f-number is the ratio of the focal length to the diameter of the aperture. The aperture is the circular opening through which light travels before reaching the lens. Table 1 shows the dependence of the depth of field (DOF) upon the f-number of a digital camera. Table 1: Dependence of Depth of Field Upon f-Number and Camera Lens 35-mm Camera Lens 200-mm Camera Lens f-Number DN (m) DF (m) DOF (m) DN (m) DF (m) DOF (m) 2.8 4.11 6.39 2.29 4.97 5.03 0.06 4.0 3.82 7.23 3.39 4.95 5.05 0.10 5.6 3.48 8.86 5.38 4.94 5.07 0.13 8.0 3.09 13.02 9.93 4.91 5.09 0.18 22.0 1.82 Infinity Infinite 4.775 5.27 0.52 The DN value represents the nearest object distance that is acceptably focused. -
Investigation of Driver's FOV and Related Ergonomics Using Laser Shadowgraphy from Automotive Interior
of Ergo al no rn m u ic o s J Hussein et al., J Ergonomics 2017, 7:4 Journal of Ergonomics DOI: 10.4172/2165-7556.1000207 ISSN: 2165-7556 Research Article Open Access Investigation of Drivers FOV and Related Ergonomics Using Laser Shadowgraphy from Automotive Interior Wessam Hussein1*, Mohamed Nazeeh1 and Mahmoud MA Sayed2 1Military Technical College, KobryElkobbah, Cairo, Egypt 2Canadian International College, New Cairo, Cairo, Egypt *Corresponding author: Wessam Hussein, Military Technical College, KobryElkobbah, 11766, Cairo, Egypt, Tel: + 20222621908; E-mail: [email protected] Received date: June 07, 2017; Accepted date: June 26, 2017; Publish date: June 30, 2017 Copyright: © 2017 Hussein W, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abstract A new application of laser shadowgraphy in automotive design and driver’s ergonomics investigation is described. The technique is based on generating a characterizing plot for the vehicle’s Field of View (FOV). This plot is obtained by projecting a high divergence laser beam from the driver’s eyes cyclopean point, on a cylindrical screen installed around the tested vehicle. The resultant shadow-gram is photographed on several shots by a narrow field camera to form a complete panoramic seen for the screen. The panorama is then printed as a plane sheet FOV plot. The obtained plot is used to measure and to analyse the areal visual field, the eye and nick movement ranges in correlation with FOV, the horizontal visual blind zones, the visual maximum vertical angle and other related ergonomic parameters.