Photographic innovations

Photography has been around for a long time now and a lot of cool things have been invented or discovered as side-effects of photography. There are many websites about the history of photography which will give a complete picture (excuse the pun) but I wanted to pick out my favourite innovation of each decade since the first permanent photograph. Yes, I said my favourite, not necessarily the most important 🙂

1820s: First permanent photograph

Both the camera obscura and the fact that some materials are affected by light had been known about for centuries beforehand, but they were brought together for the first time in 1826 or 1827 by Nicéphore Niépce. This photograph was created by coating a pewter plate with bitumen and using sunlight to selectively harden the bitumen, allowing the rest to be washed away with lavender oil. The results were crude and exposures typically required several days. However, the seeds were sown for people to work at improving the process.

1830s: First short-exposure photograph

In the late 1830s, Louis Daguerre, a former partner of Niépce invented the Daguerrotype. The Daguerrotype process produced one-of-a-kind positives in camera. The process was complex and required unpleasant chemicals but exposure times could be as short as a couple of minutes in sunlight. This leap in technology made it much easier for professional photographers to take portraits.

1840s: Petzval portrait lens

While the Daguerrotype had gone some of the way towards decreasing the length of exposures by inventing a more sensitive plate, the next breakthrough was to address the other half of the equation: a faster lens. The Petzval portrait lens had a fast aperture of f/3.6, about four stops faster than the previous generations of meniscus lens which usually clocked in at between f/14 and f/16. It wasn’t without its flaws, and as its name suggests, the Petzval portrait lens was used mostly for portraiture. Landscape and still life photographers, for whom speed wasn’t an issue, still used slower lenses with fewer aberrations.

1850s: Collodion

The invention of the wet-plate collodion process in the 1850s enabled negatives to be made on transparent glass plates for the first time, rather than translucent paper or opaque metal plates. This meant it was possible to take one negative in the camera and then contact-print as many identical positives as required. The collodion process was also faster than anything before it, requiring mere seconds to expose a wet plate. The ability to produce many positives from one negative is the cool bit here, and underpins practically all darkroom developments that follow.

1860s: First colour photograph using filtered B&W

Colour photography has been around for a lot longer than many people realise. In 1861, Thomas Sutton took the first colour photograph, using a three-colour process with glass filters and black & white plates. Negatives were made by photographing the same subject three times through red, green and blue filters. The three black & white plates were then recombined by projecting them on top of each other with three projectors, each having a red, green or blue filter. The experiment was a partial success, limited by the fact that glass plate negatives of the day were not really sensitive to red light. Points for trying, though.

1870s: Dry plate photography

Up until the 1870s, wet photographic plates had to be prepared immediately before exposure, used before they dried, and developed immediately after. This meant that photographers were usually constrained to their studios and darkrooms, and if they wanted to take photos outside they needed to take a portable darkroom in a tent or caravan. By the end of the 1870s, George Eastman (who would go on to found Kodak) was manufacturing pre-prepared dry gelatin plates which could simply be purchased, exposed and developed later. The enormously simplified workflow allowed photographers to be more productive and to work further from the studio.

1880s: Film

The innovation of dry plates in the 1870s had made it a lot easier to take photographs on the move but it got a whole lot easier again in the 1880s with the invention of film. In the past, photographic plates had been made of glass or metal, and were heavy. They would have been carried around in lightproof wooden boxes and a photographer would have been limited by the number of shots they could take. Film had a very similar emulsion to dry plates, but was coated on a flexible base which was much thinner and lighter. It was available in sheets (cut film) and on rolls (roll film).

When roll film was invented, it was only what we now know as medium format roll film. Compared to the large glass plates and cut film that were in regular use at the time, medium format roll film was small and did not have the same resolution and so found itself targeted at the consumer market (more on that soon). However, it was now possible for a photographer to carry many more exposures around.

1890s: Cooke triplet

In 1893, the Cooke triplet was patented. It was the first major advancement on the Petzval portrait lens from the 1840s and improved on the design by correcting most distortions and aberrations from the outer edges of the image. The design was so good that it is still used in inexpensive cameras today – including some phone cameras.

1900s: Kodak Brownie

The Kodak Brownie is probably one of the best known brands in photography. It was a low-quality camera made from cardboard and equipped with a meniscus lens but it was sold for only $1, putting photography into the hands of amateurs for the first time. It used roll film for convenience and ultimately led to our culture today where everybody was able to carry a camera in their pocket.

1910s: First 35mm camera

Up until the 1910s, most cameras had been large, heavy cameras that needed a tripod. The ones that weren’t heavy were mostly low quality consumer cameras, like the Kodak Brownie. The modern trend of high-precision miniaturisation started as several manufacturers dabbled with prototype cameras that borrowed 35mm motion picture film and used it for still images. By this time, films were improving in resolution all the time and “miniature” negatives were becoming acceptable in quality.

The most well-known (although not the first) of these early 35mm cameras was the Ur-Leica, which was prototyped in 1913  by Oskar Barnack, although not produced until 1923. The Ur-Leica and other contemporary models paved the way for small but extremely high quality cameras, lenses and film which would set the scene for almost the next century.

1920s: First flash bulb

We’ve already discussed various advances in lenses and in film/plate technology which helped bring exposure time down from days to seconds over the previous 50 years. Still most photographs were taken using sunlight though – either outdoors, or relying on large windows in photographic studios. Some photographers were able to use electric “hot lights” or magnesium flash powder indoors but these were expensive, impractical and the latter was quite dangerous.

In the 1920s, the first single-use flash bulbs were invented. They burned magnesium or aluminium foil in a glass bulb safely and without fumes. Suddenly, indoor photography was much more accessible. The use of flash bulbs continued for several decades until they were replaced by the electronic flash we know today.

1930s: Kodachrome colour film

There were various attempts at colour photography going back to the 1860s, some better than others. Technicolor, dating from 1916, was a successful method of making colour movies using multiple black & white film strips with coloured filters, using a similar technique to Sutton in 1861, and requiring special equipment.

Kodachrome was one of the first successful single-strip colour films for use in normal cameras, which found widespread adoption in motion picture and still photography from its introduction in 1935 until its discontinuation in 2010. Kodachrome offered saturated colours and excellent archival properties which made it a firm favourite.

1940s: Lens coatings

According to the laws of optics, every piece of glass in an optical system comes with aberrations. Good quality lenses must use several glass elements to cancel out each other’s aberrations. The simplest meniscus lenses have just one element and suffer from very soft images. The Petzval portrait has four and the Cooke triplet has three. More complex lenses have more – modern zoom lenses have anywhere between 10 and 20 elements. With just bare glass, each element loses about 4% of the light going through it is reflected back. With multiple elements, suddenly the light loss through the whole lens can become significant and internal reflections can ruin the contrast in an image, especially when shooting towards the sun.

In the late 1930s, a scientist working for Zeiss discovered interference-based lens coatings which reduced the light loss to 1%. These coatings were used on German binoculars and other military optics and remained a military secret until after the war, when they quickly found their way into camera lenses.

Coated lenses offered better light transmission, higher contrast and less flare, massively improving the quality of photographs. As with all technologies, incremental improvements afterwards continued to improve lens coatings and today, almost all lenses have multiple coatings on each element, tailored to the specific needs.

1950s: Retrofocus lenses

When we consider a theoretical lens of focal length 50mm, the optical centre of the lens has to be 50mm away from the film. To zoom out, you use a lens of shorter focal length, and this also means moving the lens closer to the film. To make matters worse, the optical centre of the lens is usually about in the middle of the lens barrel – meaning for a 50mm lens you actually have to get the lens closer to the film than 50mm – this is called the flange focal distance. With the classic (mirrorless) rangefinder design, you can’t make a lens with a focal length much shorter than 35mm without the lens touching the shutter.

In 1950, Pierre Angénieux introduced a new retrofocus lens design that uses an inverted telephoto layout, meaning the distance between the optical centre of the lens and the film can actually be greater than the focal length of the lens, for example a 28mm lens can be 40mm away from the film. This breakthrough meant it was possible to make lenses of shorter focal lengths that don’t touch the shutter, and for the first time the SLR (invented about 15 years earlier) became a viable option with a range of lenses to compete with rangefinders.

Without retrofocus lenses, the shortest focal length possible for an SLR was about 50mm. With retrofocus, it was possible to make SLR lenses with focal lengths of less than 20mm. The retrofocus design is still in widespread use today – the 18mm focal length found on many DSLR kit zoom lenses is much further from the sensor than 18mm.

1960s: TTL metering with CdS cells

Electronic light meters had been around since the 1930s, albeit the insensitive and inaccurate selenium type. In the 1960s, cadmium sulphide (CdS) meters became popular, which were much more sensitive. Almost all selenium meters required a match-needle and worked by having a selenium cell on top of the camera, which pointed generally in the direction of the camera.

CdS cells were just the enabler – the real innovation was through-the-lens (TTL) metering, where the CdS meter was placed somewhere inside the viewfinder assembly of an SLR and could “see” through the main lens, metering exactly what would be included in the picture. This more accurate method of metering paved the way for coupled metering and eventually full autoexposure.

1970s: Consumer zoom lens; autoexposure

The 1970s was a good decade for photography and I couldn’t decide between two key innovations, so I’m going to mention both.

The first zoom lens was invented in 1902 for movie cameras. Pierre Angénieux (of retrofocus lens fame) designed the first practical zoom lens for still camera use in 1958, but it wasn’t until the 1970s that zoom lenses were good enough and cheap enough to be commercially viable. In 1977, the Fujica AZ-1 was the first camera to be bundled with a kit lens that was a zoom lens rather than a prime. Today, zoom lenses are the dominant type.

Just sneaking in at the tail end of the 1970s, the first camera to be released with full autoexposure was the Canon A-1 in 1978. Coupled metering had been around for a while, but program autoexposure was able to set the aperture and the shutter speed according to light conditions, needing no involvement from the photographer.

1980s: Autofocus

Several manufacturers started dabbling with assisted focusing technologies in the late 1970s but the first true autofocus cameras came in the early 1980s. Photographers are split whether they love or loathe autofocus but there’s no doubt it revolutionised the fields of sports and wildlife photography, and ultimately lead to making photography easier for casual shooters.

The first SLR with autofocus was the Pentax ME-F, pictured above. Early autofocus systems were slow and inaccurate and something of a gimmick but as with all cool new stuff, it was refined over time to become the fast and accurate autofocus systems we have in professional DSLRs these days.

1990s: Digital photography

The first ever digital camera was created in the 1970s but in the 1991 the first commercially-available digital cameras hit the consumer market – the Kodak DCS 100, which was based on a Nikon 35mm SLR with a digital back and a “portable” external processing and storage unit. Early DSLRs handled like 35mm SLRs in most respects, except that the film had been switched for a digital CCD sensor.

Early models had significantly worse resolution and noise characteristics than film, and they took a while to catch on. However the convenience couldn’t be argued with and the market was hooked, especially press photographers. Over the next few years, the technology improved and more photographers made the switch.

2000s: First CMOS DSLR

Progress with DSLRs had been steady but one of the major leaps was the switch to replace CCD sensors with CMOS ones. In the past, CMOS sensors had been inferior and cheaper, and usually used in low-cost devices like webcams.

CMOS technology had come on in leaps and bounds, and when DSLRs were equipped with modern CMOS sensors they were capable of good performance at high ISO and video too, plus faster read-out.

2010s: Mirrorless cameras

The 2010s are only half done but a major theme so far is the return to mirrorless cameras, more in keeping with the rangefinders of the pre-SLR era. This design is enabled by CMOS sensors having live view ability, allowing designers to do away with the reflex mirror and prism. Mirrorless cameras have the same high quality sensors as DSLRs but with a smaller size and weight. The jury is still out whether mirrorless cameras will ever replace DSLRs, but they are definitely selling well.

So there you have it. A highlight of my favourite innovations in photographic technology over the past 190 years. I hope you enjoyed reading 🙂