This made handheld photography possible in situations where a tripod might otherwise have been needed, and offered photographers much more mobility. Chromatic aberration was suppressed with two UD lenses and the lens was developed for high resolution and contrast. Lens coatings are not the most glamorous-sounding lens technology, but they are one of the most important, playing a vital part in the suppression of ghosting, flare and contrast loss.
The SWC coating adopted for this lens has a structure finer than the wavelength of visible light, which was the first time this had ever been done. This minimised flare and ghosting caused by large angles of incidence, which could not be prevented with regular coatings. The SWC system was earmarked as one of Canon's key technologies for future development. Macro photography poses special problems for image stabilisation systems because it introduces a second type of potential camera movement parallel to the camera position.
In addition to a regular angular shake sensor, this lens introduced an additional acceleration sensor for movement parallel to the image plane. Data generated by the two sensors was used to drive the optical correction unit using specially-developed algorithms, and brought improved shake correction for macro photography.
The fluorocarbon coating is water- and oil-repellent, and even if dust does stick to the surface, it's easier to remove. The fluorine coating also makes it possible to wipe away finger grease, for example, without solvents.
Fisheye lenses come in two types: circular fisheyes, which create a fully circular image within the frame area, and diagonal fisheyes which fully fill the frame area with a rectangular image.
Normally, if you want both types you have to buy two lenses, but in Canon launched the first lens to offer both a full degree circular image to a full-frame diagonal degree field of view in a single lens.
At the widest focal length a circular image is produced and this enlarges to fill the frame because the zoom setting is increased, with a marker on the zoom ring showing the point where the view fills the frame. Teleconverters — often known as 'extenders' — are widely used by sports and wildlife photographers to extend the reach of telephoto lenses. The gain in focal length is offset by a loss in maximum aperture, so they work best with a lens that has a wide maximum aperture to start with.
Not only that, it can also be used with a regular EF 1. ASC stands for Air Sphere Coating, a film which contains 'balls of air', which is evaporated on to the lens surface as a thin film. This strange-sounding coating provides a large reduction in flare and ghosting at light angles close to perpendicular, making it particularly suitable for telephoto lenses and their relatively narrow angles of view. The lens also makes use of one fluorite lens and one super UD lens, plus an image stabiliser unit offering four stops of shake compensation.
It makes use of some of Canon's key imaging and manufacturing technologies — including a ground aspherical lens, UD and super-UD lenses for chromatic aberration suppression, and both SWC and ASC anti-reflection lens coatings. This makes it perfect for correcting the kind of chromatic aberration found in large aperture lenses. There is high image quality from the centre to the edge of the frame, and excellent performance even wide open, allowing the unusual combination of a wide angle of view and shallow depth of field for creative background blur.
Wide-aperture prime lenses are not new. Note that the codes have become less common on recent lenses, with serial numbers in a different 'xx y zzzzzzz' format. The remaining seven digits '' are a basic serial number this was a very early lens - one of the first shipped in the UK.
How to interpret the date code? It's been suggested that the code starts in January with the number 38 and increments each month of the year. We believe the code was reset to 01 for Jan - but this is still not known for certain. The figures here should be taken as a guide.
The second letter, "R" , is a year code that indicates the year of manufacture. Canon increments this letter each year starting with A in and prior to that, A in without the leading factory code. Here is a table to make things simple:. The first two numbers, "09" , is the month number the lens was manufactured in.
The leading zero of the month code is sometimes omitted. The next two numbers, "02" , are meaningless in determining how old a Canon lens is. This is a Canon internal code that is occasionally omitted.
While you now know the manufacture date for your lens, you do not know how long the lens was in inventory, in shipping transit, and on a shelf until it was originally purchased without having the original receipt or a reputable person accurately informing you. Click here to get inspiring stories and exciting news from Canon Europe Pro.
Sign up now. Canon Logo. Robots to hand polishing: 10 facts from Canon's L-series lens factory. Canon's Utsunomiya lens factory is kept pristine, with all workers and visitors wearing protective clothing in the dust-free environment. Japanese engineering is everywhere Around km north of Tokyo, Japan a minute journey by bullet train , lies Canon's Utsunomiya lens factory, the main production hub for L-series lenses. In the initial stages of the lens creation, a plate covered with diamond discs is used for shaping and then smoothing the raw lens.
Master craftsmen are at the heart of lens creation. Here, Toshi Saito starts the process of creating the initial lens, before it is taken on by automated machines.
Lens experts can hear faults While much of the lens manufacturing process is automated, expert craftsmen, called Takumi 'skilled artisan' , play an important role in lens creation. Lens polishing tools are made with diamonds. Do you own Canon kit? Lenses are designed using CAD software that accounts for the physical and optical properties of the different glasses being used — whether the metal oxides and other material particles are arranged in regular crystal , irregular glass or in between amorphous patterns defines how the glass behaves.
Each glass element in a lens is ground, smoothed and polished to the precise profile required, with polishing tools made from diamond grindstone-covered plates. Firstly, the glass is ground blank, to remove excess thickness, before it is smoothed, to reduce cracks.
The third stage is centring, during which the edges of the lens are ground down to ensure the lens is optically centred. Then it's polished further to smooth tiny surface cracks, finalise the shape, and turn it transparent.
The lens is then ready for inspection. Aspherical lenses are made by melting glass Glass is the best material for making lenses — being transparent, relatively easy to shape and thermally and chemically stable — but it can be hard to work with.
Canon uses delivery robots, fitted with sensors to avoid collisions, to get parts to the right destination on time. Sci-fi robots roam the factory With long distances to cover on the Utsunomiya factory floors, automated delivery robots speed around, carrying their precious cargo to various stations.
Lens polishing machines self-correct. Inside a sports photographer's kitbag Getty Images' Warren Little reveals his favourite Canon camera, lenses and accessories for capturing Rugby World Cup action.
Automation also helps in the manufacturing process, such as when Canon's lens polishing machines come into play.
Operators oversee the process, ensuring the machines, which have been developed in-house, are functioning correctly. But the machines can also self-correct — they automatically measure lens elements at two points in the production process, and act on any deviations from the design profile, correcting that lens and tweaking parameters so that the next one they produce is as close as possible to the design ideal.
Despite the importance of automated technology, there are some things, such as the expertise of the Takumi, that can't be replaced. Every Canon L-series mm lens — not just the samples — is tested and calibrated by hand using a complex nine-point optical test process, ensuring that each lens meets the high standard expected in the premium line.
The lens inspection area where Canon lenses are tested.
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