Photography History

The first permanent photograph was an image produced in 1826 by the French inventor Joseph Nicéphore Niépce.

Nicéphore Niépce's earliest surviving photograph of a scene from nature, circa 1826, "View from the Window at Le Gras," Saint-Loup-de-Varennes (France).

Etymology

The word photography derives from the Greek words phōs (genitive: phōtós) light, and gráphein, to write. The word was coined by Sir John Frederick William Herschel in 1839.

Technological background

A camera obscura used for drawing images

Photography is the result of combining several different technical discoveries. Long before the first photographs were made, Chinese philosopher Mo Ti and Greek mathematicians Aristotle and Euclid described a pinhole camera in the 5th and 4th centuries BC. In the 6th century CE, Byzantine mathematician Anthemius of Tralles used a type of camera obscura in his experiments
Ibn al-Haytham (Alhazen) (965–1040) studied the camera obscura and pinhole camera, Albertus Magnus (1193/1206–80) discovered silver nitrate, and Georges Fabricius (1516–71) discovered silver chloride. Daniel Barbaro described a diaphragm in 1568. Wilhelm Homberg described how light darkened some chemicals (photochemical effect) in 1694. The novel Giphantie (by the French Tiphaigne de la Roche, 1729–74) described what can be interpreted as photography.

Early History: Development of chemical photography

Monochrome process

"Boulevard du Temple", taken by Louis Daguerre in late 1838 or early 1839,.. was the first-ever photograph of people. It is an image of a busy street, but because exposure time was over ten minutes, the city traffic was moving too much to appear. The exceptions are the two people in the bottom left corner, one who stood still getting his boots polished by the other long enough to show up in the picture.

Robert Cornelius, self-portrait, Oct. or Nov. 1839, approximate quarter plate daguerreotype. The back reads, "The first light picture ever taken."

One of the oldest photographic portraits known, made by Joseph Draper of New York, in 1839 or 1840, of his sister, Anna Katherine Draper.

The first permanent photograph was an image produced in 1826 by the French inventor Joseph Nicéphore Niépce. His photographs were produced on a polished pewter plate covered with a petroleum derivative called bitumen of Judea, which he then dissolved in white petroleum.^[7] Bitumen hardens with exposure to light. The unhardened material may then be washed away and the metal plate polished, rendering a positive image with light regions of hardened bitumen and dark regions of bare pewter. Niépce then began experimenting with silver compounds based on a Johann Heinrich Schultz discovery in 1727 that silver nitrate (AgNO₃) darkens when exposed to light.
In partnership, Niépce (in Chalon-sur-Saône) and Louis Daguerre (in Paris) refined the existing silver process. In 1833 Niépce died of a stroke, leaving his notes to Daguerre. While he had no scientific background, Daguerre made two pivotal contributions to the process. He discovered that exposing the silver first to iodine vapour before exposure to light, and then to mercury fumes after the photograph was taken, could form a latent image. Bathing the plate in a salt bath then fixes the image. On January 7, 1839 Daguerre announced that he had invented a process using silver on a copper plate called the daguerreotype, and displayed the first plate. The French government bought the patent and almost immediately (on August 19 of that year) made it public domain.
In 1832, French-Brazilian painter and inventor Hercules Florence had already created a very similar process, naming it Photographie.
After reading about Daguerre's invention, Fox Talbot worked on perfecting his own process; in 1839 he acquired a key improvement, an effective fixer, from John Herschel, the astronomer, who had previously showed that hyposulfite of soda (also known as hypo, or now sodium thiosulfate) would dissolve silver salts. Later that year, Herschel made the first glass negative.

A calotype print showing the American photographer Frederick Langenheim (circa 1849). Note, the caption on the photo calls the process Talbotype

By 1840, Talbot had invented the calotype process. He coated paper sheets with silver chloride to create an intermediate negative image. Unlike a daguerreotype, a calotype negative could be used to reproduce positive prints, like most chemical films do today. The calotype had yet another distinction compared to other photographic processes of the day, in that the finished product lacked fine clarity due to its translucent paper negative. This was seen as a positive attribute for portraits because it softened the appearance of the human face. Talbot patented this process, which greatly limited its adoption. He spent the rest of his life in lawsuits defending the patent until he gave up on photography. Later George Eastman refined Talbot's process, which is the basic technology used by chemical film cameras today. Hippolyte Bayard had also developed a method of photography but delayed announcing it, and so was not recognized as its inventor.
In 1839, John Herschel made the first glass negative, but his process was difficult to reproduce. Slovene Janez Puhar invented a process for making photographs on glass in 1841; it was recognized on June 17, 1852 in Paris by the Académie Nationale Agricole, Manufacturière et Commerciale. In 1847, Nicephore Niépce's cousin, the chemist Niépce St. Victor published his invention of a process for making glass plates with an albumen emulsion; the Langenheim brothers of Philadelphia and John Whipple of Boston also invented workable negative-on-glass processes in the mid 1840s.
In 1851 Frederick Scott Archer invented the collodion process. Photographer and children's author Lewis Carroll used this process.

Roger Fenton's assistant seated on Fenton's photographic van, Crimea, 1855.

Herbert Bowyer Berkeley experimented with his own version of collodian emulsions after Samman introduced the idea of adding dithionite to the pyrogallol developer. Berkeley discovered that with his own addition of sulfite, to absorb the sulfur dioxide given off by the chemical dithionite in the developer, that dithionite was not required in the developing process. In 1881 he published his discovery. Berkeley's formula contained pyrogallol, sulfite and citric acid. Ammonia was added just before use to make the formula alkaline. The new formula was sold by the Platinotype Company in London as Sulpho-Pyrogallol Developer.
Nineteenth-century experimentation with photographic processes frequently became proprietary. The German-born, New Orleans photographer Theodore Lilienthal successfully sought legal redress in an 1881 infringement case involving his "Lambert Process" in the Eastern District of Louisiana.

Popularization

General view of The Crystal Palace at Sydenham by Philip Henry Delamotte, 1854

Mid 19th century "Brady stand" photo model's armrest table, meant to keep portrait models more still during long exposure times (studio equipment nicknamed after the famed US photographer, Mathew Brady).

1855 cartoon satirizing problems with posing for Daguerreotypes; slight movement during exposure resulted in blurred features

A photographer appears to be photographing himself in a 19th-century photographic studio. Note clamp to hold the poser's head still. A 1893 satire on photographic procedures already becoming obsolete at the time.

A comparison of common print sizes used in photographic studios during the 19th century.

The daguerreotype proved popular in response to the demand for portraiture that emerged from the middle classes during the Industrial Revolution. This demand, that could not be met in volume and in cost by oil painting, added to the push for the development of photography.
In 1847, Count Sergei Lvovich Levitsky designed a bellows camera which significantly improved the process of focusing. This adaptation influenced the design of cameras for decades and is still found in use today in some professional cameras. While in Paris, Levitsky would become the first to introduce interchangeable decorative backgrounds in his photos, as well as the retouching of negatives to reduce or eliminate technical deficiencies. Levitsky was also the first photographer to portray a photo of a person in different poses and even in different clothes (for example, the subject plays the piano and listens to himself).
Roger Fenton and Philip Henry Delamotte helped popularize the new way of recording events, the first by his Crimean war pictures, the second by his record of the disassembly and reconstruction of The Crystal Palace in London. Other mid-nineteenth-century photographers established the medium as a more precise means than engraving or lithography of making a record of landscapes and architecture: for example, Robert Macpherson's broad range of photographs of Rome, the interior of the Vatican, and the surrounding countryside became a sophisticated tourist's visual record of his own travels.
By 1849, images captured by Levitsky on a mission to the Caucasus, were exhibited by the famous Parisian optician Chevalier at the Paris Exposition of the Second Republic as an advertisement of their lenses. These photos would receive the Exposition's gold medal; the first time a prize of its kind had ever been awarded to a photograph.
That same year in 1849 in his St. Petersburg, Russia studio Levitsky would first propose the idea to artificially light subjects in a studio setting using electric lighting along with daylight. He would say of its use, "as far as I know this application of electric light has never been tried; it is something new, which will be accepted by photographers because of its simplicity and practicality".
In 1851, at an exhibition in Paris, Levitsky would win the first ever gold medal awarded for a portrait photograph.
In America, by 1851 a broadside by daguerreotypist Augustus Washington were advertising prices ranging from 50 cents to $10 However, daguerreotypes were fragile and difficult to copy. Photographers encouraged chemists to refine the process of making many copies cheaply, which eventually led them back to Talbot's process.
Ultimately, the modern photographic process came about from a series of refinements and improvements in the first 20 years. In 1884 George Eastman, of Rochester, New York, developed dry gel on paper, or film, to replace the photographic plate so that a photographer no longer needed to carry boxes of plates and toxic chemicals around. In July 1888 Eastman's Kodak camera went on the market with the slogan "You press the button, we do the rest". Now anyone could take a photograph and leave the complex parts of the process to others, and photography became available for the mass-market in 1901 with the introduction of the Kodak Brownie.
In the twentieth century, photography developed rapidly as a commercial service. End-user supplies of photographic equipment accounted for only about 20 percent of industry revenue. For the modern enthusiast photographer processing black and white film, little has changed since the introduction of the 35mm film Leica camera in 1925.
The first digitally scanned photograph was produced in 1957. The digital scanning process was invented by Russell A. Kirsch, a computer pioneer at the National Institute of Standards and Technology. He developed the system capable of feeding a camera's images into a computer. His first fed image was that of his son, Walden Kirsch. The photo was set at 176x176 pixels.

Color process

First color image, photograph by James Clerk Maxwell, 1861.

Although color photography was explored throughout the 19th century, initial experiments in color resulted in projected temporary images, rather than permanent color images. Moreover until the 1870s the emulsions available were not sensitive to red or green light.
The first color photo, an additive projected image of a tartan ribbon, was taken in 1861 by the Scottish physicist James Clerk Maxwell. Several patentable methods for producing images (by either additive or subtractive methods, see below) were devised from 1862 on by two French inventors (working independently), Louis Ducos du Hauron and Charles Cros. Practical methods to sensitize silver halide film to green and then orange light were discovered in 1873 and 1884 by Hermann W. Vogel, but full sensitivity to red light was not achieved until the early years of the 20th century.
The first fully practical color plate, Autochrome, did not reach the market until 1907. It was based on a screen-plate method, the screen (of filters) being made using dyed dots of potato starch. The screen lets filtered red, green or blue light through each grain to a photographic emulsion in contact with it. The plate is then developed to a negative, and reversed to a positive, which when viewed through the screen restores colors approximating the original.
Other systems of color photography included that used by Sergei Mikhailovich Prokudin-Gorskii, which involved three separate monochrome exposures ('separation negatives') of a still scene through red, green, and blue filters. These required a special machine to display, but the results are impressive even by modern standards. His collection of glass plates was purchased from his heirs by the Library of Congress in 1948, and is now available in digital images.

Development of digital photography

Main article: Digital photography

The charge-coupled device (CCD) is the most important invention for digital photography^{[citation needed]}. It was invented in 1969 by Willard Boyle and George E. Smith at AT&T Bell Labs. The lab was working on the Picturephone and on the development of semiconductor bubble memory. Merging these two initiatives, Boyle and Smith conceived of the design of what they termed 'Charge "Bubble" Devices'. The essence of the design was the ability to transfer charge along the surface of a semiconductor.

• 1973 - Fairchild Semiconductor releases the first large image forming CCD chip; 100 rows and 100 columns^{[citation needed]}.
• 1975 - Bryce Bayer of Kodak develops the Bayer filter mosaic pattern for CCD color image sensors
• 1986 - Kodak scientists develop the world's first megapixel sensor.

The web has been a popular medium for storing and sharing photos ever since the first photograph was published on the web by Tim Berners-Lee in 1992 (an image of the CERN house band Les Horribles Cernettes). Today popular sites such as Flickr, Picasa and PhotoBucket are used by millions of people to share their pictures.

Basics

Studio-quality portraits are easier than most people think. Here you will find five important things to consider before snapping that photo.

Chances are if you own a camera you've tried your hand at taking portraits. And, chances are that you may have been disappointed with some of the results. You can better your chances of getting great results every time you snap the shutter just by using some very basic tips that are already old news to professional photographers. Here are four of the most important ones to consider:

1.) Lens Length

One of the easiest ways to get good portraits is with a longer lens. With a longer lens, you can stay back from your subject while still being able to fill the frame. If you move in too close, not only will your subject become uncomfortable, the closeness will also result in distorted features. You don't want a wide-angle lens to make the subject's nose appear to be the biggest thing in the shot.

With a longer lens, you can put space between you and your subject, which will put them more at ease and will result in more natural portraits.

Another reason to use a long lens is that they tend to throw everything behind the subject out of focus. This brings us to another trick of the trade, which is focus.

2.) Focus

When taking portraits, focus is one of the most important aspects of a good photo.

First, you want to make sure that you focus on the eyes of your subject. With a longer lens, as recommended earlier, your depth of field is much narrower. This means that the depth of the focused area may be so narrow that the hair could be in focus while the eyes are out of focus. Since the eyes are the attention getters, it is always important that they are in perfect focus.

And, another way to use focus is by having the subject in focus while the background and surrounding areas are out of focus. This draws attention to the subject and makes unsightly things in the background disappear into a blur. This, in turn, will make your subject stand out and results in a very pleasant photograph.

3.) Composition

Composition is, without a doubt, one of the most important secrets to getting great photos. A good eye for composition is why some can take super photos with inexpensive cameras while others can't take a decent photo with the most expensive camera in the world. There is just no substitute for good composition in the world of photography. The good news is that anyone can learn to compose a great photograph.

First, if you are taking a full body shot, remember to keep all arms, legs and feet in the shot. Cutting off someone's feet in a full-length shot makes the photo unpleasant to look at. If you can't get back far enough to include the whole body, consider an upper body or head and shoulders shot.

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With an upper body shot, you can cut the subject off at the waist and still have a nice photo. Just remember to keep the arms in the shot. If they are leading out of the shot, that's where the eyes of the viewer will want to go too.

With a head and shoulders shot, you want to keep the arms out of the shot. If too much of the upper body is shown, then the arms will once again lead the eye away from the subject. Concentrate your attention on the face and the turn of the shoulders and you should get excellent results.

When photographing children, make sure you get down to their eye level. Too many shots of children are from above their heads, which make them appear small and insignificant. If you snap the picture from a kneeling position, or even while lying down, you get a photo that is much better composed than one taken from above the subject.

4.) Lighting

Knowing a few basic lighting secrets is the next step to great portraits. All light is not created equal in the world of photography, and knowing the differences in lighting and how to use them will turn so-so pictures into prize-winning photos.

First, remember that straight-on flash photography is not the best way to get good portraits. It flattens the features and makes a dull photo. If you must use a flash, try to bounce the flash off of the ceiling or some other surface. A bounced flash will give much more pleasing light without robbing the face of its character.

Natural light, however, is a favorite of many photographers. Under the right conditions, the outdoors is the perfect portrait studio.

Remember, though, that harsh midday light can wash out the color in your photos. Early or afternoon light is best, since it is softer. Also, the light comes from the sides giving depth to a photo and accentuates the subject's features.

One thing to watch out for when taking outside photos is strong backlighting. While backlighting can result in some stunning photos, as when the hair has a halo effect, backlighting can also cast strong shadows onto your subject causing their face to be silhouetted against the bright light. To avoid this, you may want to use a fill flash to cast extra light onto the subject's face, bringing their features out of the shadows.

All About Portraits

Portrait photography or portraiture is a photography of a person or group of people that displays the expression, personality, and mood of the subject. Like other types of portraiture, the focus of the photograph is usually the person's face, although the entire body and the background may be included.

History

Portrait photography has been around since the invention and popularization of the camera. The relatively low cost of the daguerreotype in the middle of the 19th century led to its popularity for portraiture. The style of these early works reflected the technical challenges associated with long exposure times and the painterly aesthetic of the time. Subjects were generally seated against plain backgrounds and lit with the soft light of an overhead window and whatever else could be reflected with mirrors. Advances in photographic equipment and techniques developed, gave photographers the ability to capture images with shorter exposure times and allowed photographers to take portrait outside of a studio.

Lighting for portraiture

Winter portrait of a 10-month old baby girl

When portrait photographs are composed and captured in a studio, the professional photographer has control over the lighting of the composition of the subject and can adjust direction and intensity. There are many ways to light a subject's face, but there are several common lighting plans which are easy enough to describe.

Three-Point Lighting

One of the most basic lighting plans is called three-point lighting. This plan uses three (and sometimes four) lights to fully model (bring out details and the three-dimensionality of) the subject's features. The three main lights used in this light plan are as follows:

The Key light

Also called a main light, the key light is usually placed to one side of the subject's face, between 30 and 60 degrees off center and a bit higher than eye level. The key light is the brightest light in the lighting plan.

The Fill light

Placed opposite the key light, the fill light fills in or softens the shadows on the opposite side of the face. The brightness of the fill light is usually between 1/3 and 1/4 that of the key light. This is expressed as a ratio as in 3:1 or 4:1. When the ratio is 3:1 this is sometimes called Kodak lighting since this was the ratio suggested by Kodak in the instructional booklets accompanying the company's early cameras.
The purpose of these two lights is to mimic the natural light created by placing a subject in a room near a window. The daylight falling on the subject through the window is the Key light and the Fill light is reflected light coming from the walls of the room. This type of lighting can be found in the works of hundreds of classical painters and early photographers and is often called Rembrandt lighting.

The Back light

Also called a rim light or hair light, the rim light (the third main light in the three-point lighting plan) is placed behind the subject, out of the picture frame, and often rather higher than the Key light or Fill. The point of the rim light is to provide separation from the background by highlighting the subject's shoulders and hair. The rim light should be just bright enough to provide separation from the background, but not as bright as the key light.
Sometimes the rim light is set just off to the side, on the fill light side. This can add edge detail to the shadowed side of your model's face. This can add the effect of having a kicker light using only the three basis lights of three point lighting.

The Kicker

The "fourth light" in three point lighting, a kicker is a small light, often heavily gobo-ed, snooted or barn doored to limit its coverage, that adds a bright edge light on the fill light side of your model's face. The placement and brightness of a kicker is a matter of taste and technique. A kicker can also a light used to kick start another light.

Butterfly lighting

Butterfly lighting uses only two lights. The Key light is placed directly in front of the subject, often above the camera or slightly to one side, and a bit higher than is common for a three-point lighting plan. The second light is a rim light. Often a reflector is placed below the subject's face to provide fill light and soften shadows.
This lighting can be recognized by the strong light falling on the forehead, the bridge of the nose and the upper cheeks, and by the distinct shadow below the nose which often looks rather like a butterfly and thus provides the name for this lighting plan. Butterfly lighting was a favourite of famed Hollywood portraitist George Hurrell which is why this style of lighting is often called Paramount lighting.

Accessory lights

These lights can be added to basic lighting plans to provide additional highlights or add background definition.

The Kicker

A kicker is a small light, often made directional through the use of a snoot, umbrella, or softbox. The kicker is designed to add highlights to the off side of the subject's face, usually just enough to establish the jaw line or edge of an ear. The kicker should thus be a bit brighter than the fill light, but not so bright it over fills the off side of the face. Many portraitists choose not to use a kicker and settle for the three main lights of the standard plans.

Background lights

Not so much a part of the portrait lighting plan, but rather designed to provide illumination for the background behind the subject, background lights can pick out details in the background, provide a halo effect by illuminating a portion of a backdrop behind the subject's head, or turn the background pure white by filling it with light.

Other lighting equipment

Most lights used in modern photography are a flash of some sort. The lighting for portraiture is typically diffused by bouncing it from the inside of an umbrella, or by using a soft box. A soft box is a fabric box, encasing a photo strobe head, one side of which is made of translucent fabric. This provides a softer lighting for portrait work and is often considered more appealing than the harsh light often cast by open strobes. Hair and background lights are usually not diffused. It is more important to control light spillage to other areas of the subject. Snoots, barn doors and flags or gobos help focus the lights exactly where the photographer wants them. Background lights are sometimes used with color gels placed in front of the light to create coloured backgrounds.

Windowlight Portraiture

Window light used to create soft light to the portrait

Windows as a source of light for portraits have been used for decades before artificial sources of light were discovered. According to Arthur Hammond, amateur and professional photographers need only two things to light a portrait: a window and a reflector.^[1] Although window light limits options in portrait photography compared to artificial lights it gives ample room for experimentation for amateur photographers. A white reflector placed to reflect light into the darker side of the subject's face, will even the contrast. Shutter speeds may be slower than normal, requiring the use of a tripod, but the lighting will be beautifully soft and rich.^[2]
The best time to take window light portrait is considered to be early hours of the day and late hours of afternoon when light is more intense on the window. Curtains, reflectors, and intensity reducing shields are used to give soft light. While mirrors and glasses can be used for high key lighting. At times colored glasses, filters and reflecting objects can be used to give the portrait desired color effects. The composition of shadows and soft light gives window light portraits a distinct effect different from portraits made from artificial lights.
While using window light, the positioning of the camera can be changed to give the desired effects. Such as positioning the camera behind the subject can produce a silhouette of the individual while being adjacent to the subject give a combination of shadows and soft light. And facing the subject from the same point of light source will produce high key effects with least shadows.

Styles of portraiture

There are many different techniques for portrait photography. Often it is desirable to capture the subject's eyes and face in sharp focus while allowing other less important elements to be rendered in a soft focus. At other times, portraits of individual features might be the focus of a composition such as the hands, eyes or part of the subject's torso.
Additionally another style such as head shot has came out of the portraiture technique and had become a style on its own.

Approaches to Portraiture

There are essentially four approaches that can be taken in photographic portraiture — the constructionist, environmental, candid and creative approaches. Each approach has been used over time for different reasons be they technical, artistic or cultural. The constructionist approach is when the photographer in their portraiture constructs an idea around the portrait — happy family, romantic couple, trustworthy executive. It is the approach used in most studio and social photography. It is also used extensively in advertising and marketing when an idea has to be put across. The environmental approach depicts the subject in their environment be that a work, leisure, social or family one. They are often shown as doing something, a teacher in a classroom, an artist in a studio, a child in a playground. With the environmental approach more is revealed about the subject. Environmental pictures can have good historical and social significance as primary sources of information. The candid approach is where people are photographed without their knowledge going about their daily business. Whilst this approach taken by the paparazzi is criticized and frowned upon for obvious reasons, less invasive and exploitative candid photography has given the world superb and important images of people in various situations and places over the last century. The images of Parisians by Doisneau and Cartier-Bresson to name but two, demonstrate this. As with environmental photography, candid photography is important as a historical source of information about people. The Creative Approach is where digital manipulation (and formerly darkroom manipulation) is brought to bear to produce wonderful pictures of people. It is becoming a major form of portraiture as these techniques become more widely understood and used.

Lenses

Lenses used in portrait photography are classically fast, medium telephoto lenses, though any lens may be used, depending on artistic purposes. See Canon EF Portrait Lenses for Canon lenses in this style; other manufacturers feature similar ranges. The first dedicated portrait lens was the Petzval lens developed in 1840 by Joseph Petzval. It had a relatively narrow field of view of 30 degrees, a focal length of 150mm, and a fast f-number in the f/3.3-3.7 range.
Classic focal length is in the range 80–135mm on 135 film format and about 150-400mm on large format, which historically is first in photography. Such a field of view provides a flattering perspective distortion when the subject is framed to include their head and shoulders. Wider angle lenses (shorter focal length) require that the portrait be taken from closer (for an equivalent field size), and the resulting perspective distortion yields a relatively larger nose and smaller ears, which is considered unflattering and imp-like. Wide-angle lenses – or even fisheye lenses – may be used for artistic effect, especially to produce a grotesque image. Conversely, longer focal lengths yield greater flattening because they are used from further away. This makes communication difficult and reduces rapport. They may be used, however, particularly in fashion photography, but longer lengths require a loudspeaker or walkie-talkie to communicate with the model or assistants.^[3] In this range, the difference in perspective distortion between 85mm and 135mm is rather subtle; see (Castleman 2007) for examples and analysis.
Speed-wise, fast lenses (wide aperture) are preferred, as these allow shallow depth of field (blurring the background), which helps isolate the subject from the background and focus attention on them. This is particularly useful in the field, where one does not have a back drop behind the subject, and the background may be distracting. The details of bokeh in the resulting blur are accordingly also a consideration. However, extremely wide apertures are less frequently used, because they have a very shallow depth of field and thus the subject's face will not be completely in focus.^[4] Thus, f/1.8 or f/2 is usually the maximum aperture used; f/1.2 or f/1.4 may be used, but the resulting defocus may be considered a special effect – the eyes will be sharp, but the ears and nose will be soft.
Conversely, in environmental portraits, where the subject is shown in their environment, rather than isolated from it, background blur is less desirable and may be undesirable, and wider angle lenses may be used to show more context.^[5]
Finally, soft focus (spherical aberration) is sometimes a desired effect, particularly in glamour photography where the "gauzy" look may be considered flattering. The Canon EF 135mm f/2.8 with Softfocus is an example of a lens designed with a controllable amount of soft focus.
Most often a prime lens will be used, both because the zoom is not necessary for posed shots (and primes are lighter, cheaper, faster, and higher quality), and because zoom lenses can introduce highly unflattering geometric distortion (barrel distortion or pincushion distortion). However, zoom lenses may be used, particularly in candid shots or to encourage creative framing.^[6]
Portrait lenses are often relatively inexpensive, because they can be built simply, and are close to the normal range. The cheapest portrait lenses are normal lenses (50mm), used on a cropped sensor. For example, the Canon EF 50mm f/1.8 II is the least expensive Canon lens, but when used on a 1.6× cropped sensor yields an 80mm equivalent focal length, which is at the wide end of portrait lenses.