The popularity of this lens design made the name retrofocus synonymous with this type of lens. It is the standard design for wideangle and fisheye lenses in slr and cine cameras where a. Today, you can purchase distortionfree retrofocus ultra wideangle lenses as wide as 14mm 114 aov and as fast as f2. Because the optical design process is historically and quite practically closely related to ray optics, this book is intended as a companion to the field guide to geometrical optics, in which firstorder optics, thin lenses, and basic optical systems are treated in more detail. Such examples are notoriously difficult to find and the hundredodd pages of coxs book that.
These limitations become an asset when the lens is mounted in reverse and the position of the principal planes is also reversed. Singlelens reflex cameras need a certain minimum lenstofilm distance to accommodate the swinging mirror. With practical zemax examples joseph geary, are all great books, just to name a few. It was hard to keep the camera steady, transport film. Note that this compact reference is not a substitute for a. It is the standard design for wideangle and fisheye lenses in slr and cine cameras where a conventional lens would foul the shutter mechanism. The revolution in lens design that occurred from 1890 to 1905. This is achieved by incorporating a special lens group known as a telephoto group that extends the light path to create a longfocus lens in a much shorter overall design. Photographers will also learn the basics of lens design, aspheric lens elements, retrofocus lenses, shift control lenses, image stabilizers, and much more. This design is sometimes called inverted telephoto design. Nov 12, 2004 unlike the first edition, which was more a collection of lens designs for use in larger projects, the 2nd edition of modern lens design is an optical howto. My 1st attempt at an incamera multiple exposure, while testing my rb67pro with 127mm lens. Telephoto lenses have positive lenses in the front of the lens and negative lenses in the rear of the lens. The basic lens design forms are in here, and we can take a deep look into the development of lens design.
The oldest leica m lens in the book is the elmar 2. The design of the reverse telephoto is, to no ones surprise, exactly the opposite of the telephoto design. Circle of confusion from basic photographic materials and processes, stroebel et al. Retrofocus lenses, and the terms reversetelephoto and retrofocus are fairly. Retrofocus refers to a type of lens design, pioneered and originally trademarked by pierre angenieux in the early 1950s, which permits a short lens optical focal length while providing a greater back focus distance. An entire section is devoted to techniques for improving lens performance. Relay lenses use arrays or imaging lenses placed behind eyepieces to extend the length of imaging systems, such as in microscopes, endoscopes, or where proximity to a viewed object is not feasible. The ultimate guide to lens design using the classic. Sep 19, 2012 secondly, leica lenses arent retrofocus lenses. Invert the concept and you have a telephoto lens, by the way. Delving into the mechanics of lens design, this book reveals methods for designing lenses. Feb 27, 2016 angenieux wrote the book on wide angle lenses, and the term retrofocus on the lens pretty much sums that up. Aug 01, 2001 photographers will also learn the basics of lens design, aspheric lens elements, retrofocus lenses, shift control lenses, image stabilizers, and much more. But the not all the lens designs are simple lenses, we will look at newer and important lens design forms as well.
Unlike telephoto lenses, where the light is coming into the lens from a narrow field of view, a wideangle lens must deal with light coming in from well, a wide angle. Smith reveals timetested methods for designing topquality lenses. Delving deep into the mechanics of lens design, optics legend warren j. Modern lens design, 2nd edition book oreilly media. Modern lens design, 2nd edition oreilly online learning.
As lens design forms evolve, the lens use cases get more and more specialized. Smiths modern lens design helps you with every aspect of any major lens design project, including. The angenieux retrofocus for still cameras was introduced in france in 1950 by pierre angenieux. I sat on a bench at central station utrecht, the netherlands and tried a multiple exposure as an experiment, to see how this will work out. Published in 1964 and long out of print,copies of coxs a system of optical design are covered by experienced lens designers simply because a small section of the book features lens design examples. Use this book along with julie bentleys online course. We have not included any specific design examples of lenses for largeformat. Telephoto lens design allows the lens to be considerably more compact by moving the principal planes out in front of the lens. The retrofocus lens has a negative lens group at the front, and a positive lens group at the rear, and the back focal length can be made long. Because the optical design process is historically and quite practically closely related to ray optics, this book is intended as a companion to the field guide to geometrical optics, in which rstorder optics, thin lenses, and basic optical systems are treated in more detail. Back in the 1930s, the bio in biogon didnt refer to biology as it would commonly today. Also the design of faster lenses results in more elements and mirror clearance problems. A comprehensive guide to camera lens design and zeiss nomenclature.
Consequently any lens with a nominal focal length less than about 120mm is likely to be a retrofocus lens to some degree. By the late 1920s, taylor hobson had become arguably the top developer of motionpicture lenses, and had developed the reverse telephoto lens for small 8mm movie cameras. Such examples are notoriously difficult to find and the hundredodd pages of coxs book that include them are widely photocopied and constantly. First is the obliqueness of angle the light rays hit the focal plane. This advanced design employed 9 elements in 7 groups, and is decribed in detail below. Explored in detail are the terminology of lenses, how different lens types function, the. The angenieux retrofocus photographic lens is a wideangle lens design that uses an inverted telephoto configuration. Synthrays the browser based optical simulation tool. Retrofocus lenses are designed to be positioned farther from the filmsensor plane in order to leave room for an slrs reflex mirror. Field guide to lens design 2012 bentley publications. Home ebooks field guide to lens design retrofocus and wideangle lenses translator disclaimer you have requested a machine translation of selected content from our databases. Relay lenses may also be used to invert an image behind the eyepiece of.
Theory is limited to a minimum, and used to support the practical design work. It employs one or more negative lens groups at the front of the lens to increase the back focal distance of the lens. Looking at the complex designs of modern zooms, it can be somewhat difficult to see their heritage, but sometimes you can. The mounting flange on an hasselblad is about 79mm from the film plane. Non retrofocus wideangle lenses were manufactured for a relatively short period before newer retrofocus design wideangle and ultrawideangle lenses began coming to market. A telephoto design is the opposite of a retrofocus design. The problems of photographic lens design, creating a lens for a task that would cover a. Chapter 14reversed telephoto retrofocus and fisheye lenses 14. The second reason is that the reverse telephoto lens is very difficult to design. Canon 19mm lenses 1964 canon rangefinder 19mm lenses.
He deals with lens design software, primarily oslo, by far the current market leaders, and. Although the lenses get more specialized, the foundation of these lens designs is built on previous lens design forms. Field guide to lens design 2012 bentley publications spie. Lens curvature, width, position, type of glass some can be fixed, other vary with focal length, focus e. A comprehensive guide to camera lens design and zeiss. Jun 11, 2010 in practice, retrofocus design is a matter of degree rather than kind. The layout of the optical design is shown in figure 11 a. Lenses and depth of field university of california, irvine. Older 40 and 50 mm lenses are still good lenses though maybe not that perfect in the corners and at close focus. This is accomplished in the opposite way from retrofocus lenses.
The development of wideangle lenses lens rentals blog. The retro focus design allows a short focal length lens to accommodate the flangefocal distance of typical slrs, retaining infinity focus. The introduction of the computer revolutionized the way lenses optical systems are designed and evaluated. Also, there is a relationship with zoom lenses and retrofocus lenses and. The integration of modern computer optimization with classical qualitative and quantitative analysis makes this book an essential part of any optical designers library, from. A telephoto lens, in photography and cinematography, is a specific type of a longfocus lens in which the physical length of the lens is shorter than the focal length. In this paper, a novel method is proposed to design the freeform offaxis reflective imaging systems. If you have ever owned a hasselblad you most likely have a copy of ernst wildis the hasselblad manual virtual bible for hasselbald owners. Basically, the objective of a retrofocus lens has the effect of a negative element. The camera lens determines, to a great extent, the quality of the image produced in any camera and must be a major consideration when selecting a camera and lens for serious work. Its advanced a spherical, multicoated optical glass reduces flare and ensures superior outer edge image quality. In august 1964, canon introduced an extreme lens extreme in its ultrawide focal length, and extreme in the sophistication of its design and quality of its images. This back focal distance is the distance between the rear of the lens and the film plain. Retrofocus lenses are generally confined to the short focal length slr lenses typically less than about 50 mm.
A course in lens design is an instruction in the design of imageforming optical systems. Retrofocus lens is a reversed telephoto lens in which the front element is negative, moving the rear nodal plane from which the focal length is measured behind the rear of the lens. Sep, 2011 the lens also has a bit of a retrofocus design with a negative element in front and a positive group near the rear in yellow. With this book in hand, theres no lens an optical engineer or an enthusiastic amateur cant design. Dec 30, 2014 wideangle lenses also share at least two design challenges. In spite of that, a lot of lens design books and textbooks that i have read rely heavily. This is one of my very first images shot with my bronica sqb camera and a 80 mm lens on fuji nph400 roll film. This field guide provides a working reference for practicing physicists, engineers, and scientists for deciphering the nuances of basic lens design. This makes them more prone to distortion and aberration in general. Bronica sqb with 80 mm lens, kodak trix in ilfotec ddx. It deals with lens design software, primarily oslo and provides 7 comprehensive worked examples.
Retrofocus lenses are basically a regular focal length lens with a wideangle. Jul 19, 2004 older 40 and 50 mm lenses are still good lenses though maybe not that perfect in the corners and at close focus. This is an ultimate guide of lens design forms, the optical systems that are used in our world. The 80 mm lens is not a retrofocus design, in fact its construction was the reason that older hasselblads had to have a short mirror that produced vignetting with telephoto lenses in the viewfinder. The book begins with an outline of the general process before delving into aberrations, basic lens design forms, and optimization. The problems of photographic lens design, creating a lens for a task that would cover a large, flat image plane, were well known even before the invention of photography due to the development of lenses to work with the focal plane of the camera obscura. Most zoom lenses are a retrofocus design and include a prime lens group in the rear. Granted permission by zeiss, full owner of the biogon and distagon design name and former patents. Once again wildi exhibits his mastery of photographic equipment in this book, photographic lenses. You also get 7 comprehensive worked examples, all new to this edition. But to do so, the physics and elements inside the lens need be to completely different, and larger.
Unlike the first edition, which was more a collection of lens designs for use in larger projects, the 2nd edition of modern lens design is an optical howto. In use, the term telephoto usually means a longer focal length lens or position of a zoom lens and usually not a lens of telephoto design. Wideangle and sometimes normalfocus lenses for such cameras therefore use retrofocus designs. A retrofocus lens or reverse telephoto is composed of a negative lens group followed by a positive lens. But to do so, the physics and elements inside the lens need be to. Nonretrofocus wideangle lenses were manufactured for a relatively short period before newer retrofocus design wideangle and ultrawideangle lenses began coming to market. Smith, 9780071438308, available at book depository with free delivery worldwide. Beginners and experts alike will turn to this book as. This is typically required in an slr camera, to allow space for the swinging reflex mirror. A wide angle lens is also one that projects a substantially larger image circle than would be typical for a standard design lens of the same focal length. Chapter 16 handbook of optics photonics research group. Smith, and optical system design robert fischer, introduction to lens design. Practical computeraided lens design by gregory hallock smith. The ultimate guide to lens design using the classic spreadsheet method.
Download scientific diagram invertedtelephoto or retrofocus arrangement. This guide offers a complete, dedicated treatment of all types of lenses for all types of cameras, including digital. Conceptual lens design by the masters, without using expensive software, but a spreadsheet. Another relevant aspect is illustrated in the next picture, showing the light beam projection angle of the retrofocus and the biogon lens design.
What about my mamiya six from the 50s, my leica m3 or the yashica mat 124g. Most standard range zooms even today keep that pattern. Angenieux wrote the book on wide angle lenses, and the term retrofocus on the lens pretty much sums that up. Invertedtelephoto or retrofocus arrangement, with bfl efl. Zeiss wide angle lenses all share the common gon ending, which is derived from the greek word gonia meaning angle.
Retrofocus lenses are necessary because the rear element of a simple wide angle lens would be too close to the mirror of a single lens reflex still camera, the spinning mirror of a motion picture camera or the prism block of a 3 chip video camera. Lee of the taylor hobson company, the same folks who produced the cooke triplet lens, which was perhaps the most significant lens ever made. M42 angenieux retrofocus lens image by woradate pattayawan image rights retrofocus refers to a type of lens design, pioneered and originally trademarked by pierre angenieux in the early 1950s, 1 which permits a short lens optical focal length while providing a greater back focus distance. In practice, retrofocus design is a matter of degree rather than kind. Warren j smith this text features new and updated lens design tables as well as comprehensive instruction in the lens design process, both traditional and cad. Lenses and depth of field prepared by behzad sajadi. The book introduces geometrical optics, optical instruments and. Practical computeraided lens design finds that magical balance between technical depth and accessible discussion of the journey from concept to finished optical design. Lens design fundamentals rudolf kingslake, applied optics and optical design part 1 and part 2 a. The process of designing lenses is both an art and a science. Camera lenses have been discussed in a large number of books and articles.
Shortfocus, wideangle lenses are usually mounted near the film. Photographic lens design wikimili, the best wikipedia reader. The invention of the camera in the early 19th century led to an array of lens designs intended for photography. Black art of massaging the merit function optimize for all image locations all wavelengths all apertures.