Computer Vision: Projection
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Optics – Panoramic Lens Applications Revisited
Panoramic Lens Applications Revisited Simon Thibault* M.Sc., Ph.D., Eng Director, Optics Division/Principal Optical Designer ImmerVision 2020 University, Montreal, Quebec, H3A 2A5 Canada ABSTRACT During the last few years, innovative optical design strategies to generate and control image mapping have been successful in producing high-resolution digital imagers and projectors. This new generation of panoramic lenses includes catadioptric panoramic lenses, panoramic annular lenses, visible/IR fisheye lenses, anamorphic wide-angle attachments, and visible/IR panomorph lenses. Given that a wide-angle lens images a large field of view on a limited number of pixels, a systematic pixel-to-angle mapping will help the efficient use of each pixel in the field of view. In this paper, we present several modern applications of these modern types of hemispheric lenses. Recently, surveillance and security applications have been proposed and published in Security and Defence symposium. However, modern hemispheric lens can be used in many other fields. A panoramic imaging sensor contributes most to the perception of the world. Panoramic lenses are now ready to be deployed in many optical solutions. Covered applications include, but are not limited to medical imaging (endoscope, rigiscope, fiberscope…), remote sensing (pipe inspection, crime scene investigation, archeology…), multimedia (hemispheric projector, panoramic image…). Modern panoramic technologies allow simple and efficient digital image processing and the use of standard image analysis features (motion estimation, segmentation, object tracking, pattern recognition) in the complete 360o hemispheric area. Keywords: medical imaging, image analysis, immersion, omnidirectional, panoramic, panomorph, multimedia, total situation awareness, remote sensing, wide-angle 1. INTRODUCTION Photography was invented by Daguerre in 1837, and at that time the main photographic objective was that the lens should cover a wide-angle field of view with a relatively high aperture1. -
Depth-Aware Blending of Smoothed Images for Bokeh Effect Generation
1 Depth-aware Blending of Smoothed Images for Bokeh Effect Generation Saikat Duttaa,∗∗ aIndian Institute of Technology Madras, Chennai, PIN-600036, India ABSTRACT Bokeh effect is used in photography to capture images where the closer objects look sharp and every- thing else stays out-of-focus. Bokeh photos are generally captured using Single Lens Reflex cameras using shallow depth-of-field. Most of the modern smartphones can take bokeh images by leveraging dual rear cameras or a good auto-focus hardware. However, for smartphones with single-rear camera without a good auto-focus hardware, we have to rely on software to generate bokeh images. This kind of system is also useful to generate bokeh effect in already captured images. In this paper, an end-to-end deep learning framework is proposed to generate high-quality bokeh effect from images. The original image and different versions of smoothed images are blended to generate Bokeh effect with the help of a monocular depth estimation network. The proposed approach is compared against a saliency detection based baseline and a number of approaches proposed in AIM 2019 Challenge on Bokeh Effect Synthesis. Extensive experiments are shown in order to understand different parts of the proposed algorithm. The network is lightweight and can process an HD image in 0.03 seconds. This approach ranked second in AIM 2019 Bokeh effect challenge-Perceptual Track. 1. Introduction tant problem in Computer Vision and has gained attention re- cently. Most of the existing approaches(Shen et al., 2016; Wad- Depth-of-field effect or Bokeh effect is often used in photog- hwa et al., 2018; Xu et al., 2018) work on human portraits by raphy to generate aesthetic pictures. -
Step up to the Latest in Ultra-Telephoto Zoom Lenses
Lightest in its class* Shoot precisely in the moment Extremely portable, with a highly responsive AF. Now you can seize the moment with lasting effect. Step up to the latest in ultra-telephoto zoom lenses 100-400mm F/4.5-6.3 Di VC USD (Model A035) For Canon and Nikon mounts Di: For full-frame and APS-C format DSLR cameras * Among 100-400mm interchangeable lenses for DSLR cameras (as of Oct, 2017; Tamron) Tripod mount is an option. Heavyweight Performance in a Lightweight Lens Excellent AF performance meets Mobility meets precision enhanced VC (Vibration Compensation) with the A035 ultra-telephoto lens eBAND Coating delivers sharp, clear photos Focal Length: 300mm Exposure: F/8 1/500sec ISO: 200 Precise AF tracking and VC (Vibration Compensation) are essential to ultra-telephoto lens performance. Tamron’s Dual MPU high-speed control system** helps make this possible. In addition to an MPU (micro-processing unit) with a built-in DSP for superior signal processing, the A035 features a separate MPU dedicated exclusively to vibration compensation. With AF tracking and enhanced VC, you can enjoy shooting fast-moving subjects with stability and ease— even in low-light. Focal Length: 140mm Exposure: F/14 1/200sec ISO: 200 The Tamron 100-400mm F/4.5-6.3 Di VC USD (Model A035) is a highly portable, Expand your possibilities ultra-telephoto zoom lens with AF precision for shooting instantaneous movement with an optional tripod mount with the utmost clarity. With this effectively positioned, extraordinary glass LD (Low Dispersion) lens, aberrations typical with many telephoto lenses are a thing of the Using a tripod is as easy as shooting handheld with the past. -
6 Tips for Near-Macro Photography with a Telephoto Lens a Post By: Elliot Hook
6 Tips for Near-Macro Photography with a Telephoto Lens A Post By: Elliot Hook Macro photography is the art of capturing the fine detail of very small subjects that may not be able to be seen by the naked eye. Technically, to fall under the term ‘macro’, the subject should be captured with a reproduction ratio of 1:1, i.e. the subject will be captured on the sensor at 100 % life size. Macro lenses are specially designed to minimise the focussing distance, allowing the photographer to get closer to the subject and so increase the reproduction ratio. There are a number of other techniques that can be used to help achieve the desired magnification without a dedicated lens (extension tubes, close-up filters, reversing rings), however, one of less often considered techniques is to use something that you probably already have in your kit bag: a telephoto lens. Milking Bonnet Fungi (Mycena galopus) Telephoto lenses offer extreme magnification but generally have much larger minimum focussing distances pushing the photographer further from the subject and so reducing the reproduction ratio. Some telephoto lenses, when combined with camera systems utilising smaller sensors, are able to offer 1:1 magnification (‘true macro’) however, typically, telephoto lenses are limited to close-up photography, at near-macro reproduction ratios. Using a telephoto lens for this kind of work offers a couple of advantages over a dedicated macro lens that are a direct result of the large minimum focus distance. Because the working distance to the subject is in the region of 1 metre (compared to 15 – 30 cm of standard macro lenses) the risk of disturbing your subject as you compose your shot is much reduced. -
Adaptive Optics in Laser Processing Patrick S
Salter and Booth Light: Science & Applications (2019) 8:110 Official journal of the CIOMP 2047-7538 https://doi.org/10.1038/s41377-019-0215-1 www.nature.com/lsa REVIEW ARTICLE Open Access Adaptive optics in laser processing Patrick S. Salter 1 and Martin J. Booth1 Abstract Adaptive optics are becoming a valuable tool for laser processing, providing enhanced functionality and flexibility for a range of systems. Using a single adaptive element, it is possible to correct for aberrations introduced when focusing inside the workpiece, tailor the focal intensity distribution for the particular fabrication task and/or provide parallelisation to reduce processing times. This is particularly promising for applications using ultrafast lasers for three- dimensional fabrication. We review recent developments in adaptive laser processing, including methods and applications, before discussing prospects for the future. Introduction enhance ultrafast DLW. An adaptive optical element Over the past two decades, direct laser writing (DLW) enables control over the fabrication laser beam and allows with ultrafast lasers has developed into a mature, diverse it to be dynamically updated during processing. Adaptive – and industrially relevant field1 5. The ultrashort nature of elements can modulate the phase, amplitude and/or the laser pulses means that energy can be delivered to the polarisation of the fabrication beam, providing many focus in a period shorter than the characteristic timescale possibilities for advanced control of the laser fabrication for thermal diffusion, leading to highly accurate material process. In this review, we briefly outline the application modification1. Thus, by focusing ultrashort pulses onto areas of AO for laser processing before considering the 1234567890():,; 1234567890():,; 1234567890():,; 1234567890():,; the surface of the workpiece, precise cuts and holes can be methods of AO, including the range of adaptive elements manufactured with a minimal heat-affected zone. -
A Guide to Smartphone Astrophotography National Aeronautics and Space Administration
National Aeronautics and Space Administration A Guide to Smartphone Astrophotography National Aeronautics and Space Administration A Guide to Smartphone Astrophotography A Guide to Smartphone Astrophotography Dr. Sten Odenwald NASA Space Science Education Consortium Goddard Space Flight Center Greenbelt, Maryland Cover designs and editing by Abbey Interrante Cover illustrations Front: Aurora (Elizabeth Macdonald), moon (Spencer Collins), star trails (Donald Noor), Orion nebula (Christian Harris), solar eclipse (Christopher Jones), Milky Way (Shun-Chia Yang), satellite streaks (Stanislav Kaniansky),sunspot (Michael Seeboerger-Weichselbaum),sun dogs (Billy Heather). Back: Milky Way (Gabriel Clark) Two front cover designs are provided with this book. To conserve toner, begin document printing with the second cover. This product is supported by NASA under cooperative agreement number NNH15ZDA004C. [1] Table of Contents Introduction.................................................................................................................................................... 5 How to use this book ..................................................................................................................................... 9 1.0 Light Pollution ....................................................................................................................................... 12 2.0 Cameras ................................................................................................................................................ -
Choosing Digital Camera Lenses Ron Patterson, Carbon County Ag/4-H Agent Stephen Sagers, Tooele County 4-H Agent
June 2012 4H/Photography/2012-04pr Choosing Digital Camera Lenses Ron Patterson, Carbon County Ag/4-H Agent Stephen Sagers, Tooele County 4-H Agent the picture, such as wide angle, normal angle and Lenses may be the most critical component of the telescopic view. camera. The lens on a camera is a series of precision-shaped pieces of glass that, when placed together, can manipulate light and change the appearance of an image. Some cameras have removable lenses (interchangeable lenses) while other cameras have permanent lenses (fixed lenses). Fixed-lens cameras are limited in their versatility, but are generally much less expensive than a camera body with several potentially expensive lenses. (The cost for interchangeable lenses can range from $1-200 for standard lenses to $10,000 or more for high quality, professional lenses.) In addition, fixed-lens cameras are typically smaller and easier to pack around on sightseeing or recreational trips. Those who wish to become involved in fine art, fashion, portrait, landscape, or wildlife photography, would be wise to become familiar with the various types of lenses serious photographers use. The following discussion is mostly about interchangeable-lens cameras. However, understanding the concepts will help in understanding fixed-lens cameras as well. Figures 1 & 2. Figure 1 shows this camera at its minimum Lens Terms focal length of 4.7mm, while Figure 2 shows the110mm maximum focal length. While the discussion on lenses can become quite technical there are some terms that need to be Focal length refers to the distance from the optical understood to grasp basic optical concepts—focal center of the lens to the image sensor. -
A Curriculum Guide
FOCUS ON PHOTOGRAPHY: A CURRICULUM GUIDE This page is an excerpt from Focus on Photography: A Curriculum Guide Written by Cynthia Way for the International Center of Photography © 2006 International Center of Photography All rights reserved. Published by the International Center of Photography, New York. Printed in the United States of America. Please credit the International Center of Photography on all reproductions. This project has been made possible with generous support from Andrew and Marina Lewin, the GE Fund, and public funds from the New York City Department of Cultural Affairs Cultural Challenge Program. FOCUS ON PHOTOGRAPHY: A CURRICULUM GUIDE PART IV Resources FOCUS ON PHOTOGRAPHY: A CURRICULUM GUIDE This section is an excerpt from Focus on Photography: A Curriculum Guide Written by Cynthia Way for the International Center of Photography © 2006 International Center of Photography All rights reserved. Published by the International Center of Photography, New York. Printed in the United States of America. Please credit the International Center of Photography on all reproductions. This project has been made possible with generous support from Andrew and Marina Lewin, the GE Fund, and public funds from the New York City Department of Cultural Affairs Cultural Challenge Program. FOCUS ON PHOTOGRAPHY: A CURRICULUM GUIDE Focus Lesson Plans Fand Actvities INDEX TO FOCUS LINKS Focus Links Lesson Plans Focus Link 1 LESSON 1: Introductory Polaroid Exercises Focus Link 2 LESSON 2: Camera as a Tool Focus Link 3 LESSON 3: Photographic Field -
A Theoretical and Practical Introduction to Optics a Theoretical and Practical Introduction to Optics
White Paper A Theoretical and Practical Introduction to Optics A Theoretical and Practical Introduction to Optics Be honest: do you really know how to calculate the focal length of a lens? If so, you are an exception to the rule and can stop reading here !! For the rest of you, here is a second chance. Back to square one "Piece of broken glass starts forest fire"– a common headline during the summer. But how could this have happened? Due to the enormous distance between the Earth and the Sun, the Sun only appears as a tiny point emitting parallel rays of light (figure 1a) Should these parallel rays pass through a lens (or a piece of glass, which has similar characteristics) the rays would meet behind the lens at what is called the focal point. But what happens if our point of light is so near to the lens that we can not assume to have parallel rays of light? They cross each other behind the focal point (figure 1b). If we take a look at the image of our point of light at the focal points position we will see a unclear blurred spot. And so the question arises- "what is focusing?". Focusing is to increase the distance between the focal plane and the lens until the focal plane and the junction of the rays overlap each other (figure 1c). Thus, for single points of light the situation is quite simple. But what happens to the image of screws, PCBs or plates of steel? From points of light to images A point of light does not necessarily originate directly from the sun, candles or lamps, it can also result from a reflection. -
A Practical Guide to Panoramic Multispectral Imaging
A PRACTICAL GUIDE TO PANORAMIC MULTISPECTRAL IMAGING By Antonino Cosentino 66 PANORAMIC MULTISPECTRAL IMAGING Panoramic Multispectral Imaging is a fast and mobile methodology to perform high resolution imaging (up to about 25 pixel/mm) with budget equipment and it is targeted to institutions or private professionals that cannot invest in costly dedicated equipment and/or need a mobile and lightweight setup. This method is based on panoramic photography that uses a panoramic head to precisely rotate a camera and shoot a sequence of images around the entrance pupil of the lens, eliminating parallax error. The proposed system is made of consumer level panoramic photography tools and can accommodate any imaging device, such as a modified digital camera, an InGaAs camera for infrared reflectography and a thermal camera for examination of historical architecture. Introduction as thermal cameras for diagnostics of historical architecture. This article focuses on paintings, This paper describes a fast and mobile methodo‐ but the method remains valid for the documenta‐ logy to perform high resolution multispectral tion of any 2D object such as prints and drawings. imaging with budget equipment. This method Panoramic photography consists of taking a can be appreciated by institutions or private series of photo of a scene with a precise rotating professionals that cannot invest in more costly head and then using special software to align dedicated equipment and/or need a mobile and seamlessly stitch those images into one (lightweight) and fast setup. There are already panorama. excellent medium and large format infrared (IR) modified digital cameras on the market, as well as scanners for high resolution Infrared Reflec‐ Multispectral Imaging with a Digital Camera tography, but both are expensive. -
Mission to the Solar Gravity Lens Focus: Natural Highground for Imaging Earth-Like Exoplanets L
Planetary Science Vision 2050 Workshop 2017 (LPI Contrib. No. 1989) 8203.pdf MISSION TO THE SOLAR GRAVITY LENS FOCUS: NATURAL HIGHGROUND FOR IMAGING EARTH-LIKE EXOPLANETS L. Alkalai1, N. Arora1, M. Shao1, S. Turyshev1, L. Friedman8 ,P. C. Brandt3, R. McNutt3, G. Hallinan2, R. Mewaldt2, J. Bock2, M. Brown2, J. McGuire1, A. Biswas1, P. Liewer1, N. Murphy1, M. Desai4, D. McComas5, M. Opher6, E. Stone2, G. Zank7, 1Jet Propulsion Laboratory, Pasadena, CA 91109, USA, 2California Institute of Technology, Pasadena, CA 91125, USA, 3The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA,4Southwest Research Institute, San Antonio, TX 78238, USA, 5Princeton Plasma Physics Laboratory, Princeton, NJ 08543, USA, 6Boston University, Boston, MA 02215, USA, 7University of Alabama in Huntsville, Huntsville, AL 35899, USA, 8Emritus, The Planetary Society. Figure 1: A SGL Probe Mission is a first step in the goal to search and study potential habitable exoplanets. This figure was developed as a product of two Keck Institute for Space Studies (KISS) workshops on the topic of the “Science and Enabling Technologies for the Exploration of the Interstellar Medium” led by E. Stone, L. Alkalai and L. Friedman. Introduction: Recent data from Voyager 1, Kepler and New Horizons spacecraft have resulted in breath-taking discoveries that have excited the public and invigorated the space science community. Voyager 1, the first spacecraft to arrive at the Heliopause, discovered that Fig. 2. Imaging of an exo-Earth with solar gravitational Lens. The exo-Earth occupies (1km×1km) area at the image plane. Using a 1m the interstellar medium is far more complicated and telescope as a 1 pixel detector provides a (1000×1000) pixel image! turbulent than expected; the Kepler telescope According to Einstein’s general relativity, gravity discovered that exoplanets are not only ubiquitous but induces refractive properties of space-time causing a also diverse in our galaxy and that Earth-like exoplanets massive object to act as a lens by bending light. -
Camera Settings Guide
Camera Settings Guide • " " and " " are trademarks or registered trademarks of Sony Corporation. • All other company and product names mentioned herein are used for identification purposes only and may be the trademarks or registered trademarks of their respective owners. TM and ® symbols are not included in this booklet. • Screen displays and effects used to illustrate some functions are simulated. Conventional autofocus has until now dealt with space alone. Sony goes one step further — a big step, with an innovative image sensor that picks up both space and time to capture moving subjects with new clarity. Sony spells the beginning of a new autofocus era. 4D FOCUS allows you to take crisper photos than ever. Plain old autofocus is a thing of the past. The future of photography is in motion. What is 4D FOCUS? Space: 3D Time: 4D 4D FOCUS Area Depth Time Wide Fast Steadfast The wide AF area, covering nearly the Fast Hybrid AF, combining phase- An advanced AF algorithm accurately entire frame, allows focusing on a detection AF and contrast-detection AF, predicts subject’s next move. Precise AF subject positioned even off the center instantly detects distance to the subject tracking allows focus to be maintained of the frame. to focus accurately. even on fast-moving subjects. Meeting your focusing demands Basic AF performance of Wide Fast Steadfast Focusing over wide area Instant focusing! Once it's focused, it never lets go The 6000 employs a focal plane phase- Advanced Fast Hybrid AF combines phase- With Focus Mode set to AF-C, the camera detection AF sensor with 179 AF points spread detection AF and contrast-detection AF to achieve displays one or more small green frames to cover nearly the entire frame.