Nikon from A to Z

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Flashbulbs

The earliest flashes had of a quantity of thermite flash powder that was ignited by hand. Later, magnesium filaments were contained in flash bulbs, and electrically ignited by a contact in the camera shutter; such a bulb could only be used once, and was too hot to handle immediately after use, but the confinement of what would otherwise have amounted to a small explosion was an important advance. An innovation was coating flashbulbs with a blue plastic coating to match the spectral quality to daylight balanced colour film and to make it look more moderate, as well as providing shielding for the bulb in the unlikely event of it shattering during the flash. Later bulbs substituted zirconium for the magnesium, which produced a brighter flash and tended to blind people.

Flashbulbs took longer to reach full brightness and burned for longer than electronic flashes. Slower shutter speeds (typically from 1/10 to 1/50 of a second) were used on cameras to ensure proper synchronization. A widely used flashbulbs through the 1960s was the number 25. This is the large (approximately 1 inch (25 mm) in diameter) flashbulb often shown used by newspapermen in period movies, usually attached to a press camera or a twin-lens reflex camera.

Flashcubes, Magicubes and Flipflash

In the late 1960s, Kodak improved their Instamatic camera line by replacing the individual flashbulb technology (used on early Instamatics) with the Flashcube. Flashcubes consisted of four electrically fired flashbulbs with an integral reflector in a cube-shaped arrangement that allowed taking four images in a row. A mechanism in the camera automatically rotated the flashcube 90 degrees to a fresh bulb upon advancing the film to the next exposure.

The later Magicube (or X-Cube) retained the four-bulb format, and was superficially similar to the original Flashcube. However, the Magicube did not require electrical power- each bulb was set off by a plastic pin in the cube mount that released a cocked spring wire within the cube. This wire, in turn, struck a primer tube, at the base of the bulb, which contained a fulminate. The fulminate ignited shredded zirconium foil in the flash and, thus, a battery was not required. Magicubes could also be fired by inserting a thin object, such as a key or paper clip, into one of the slots in the bottom of the cube.

Flashcubes and Magicubes are superficially similar but not interchangeable. Cameras requiring flashcubes have a round socket and a round hole for the flashcube's pin, while those requiring Magicubes have a round shape with protruding studs and a square socket hole for the Magicube's square pin. The Magicube socket can also be seen as an X, which accounts for its alternate name, X-Cube.

Another common flashbulb-based device was the Flipflash which included ten or so bulbs in a single unit. The name derived from the fact that once half the flashes had been used up, the unit had to be flipped and re-inserted to use the remainder.

Modern flash technology

Today's flash units are often electronic flashtubes. An electronic flash contains a tube filled with xenon gas, where electricity of high voltage is discharged to generate an electrical arc that emits a short flash of light. (A typical duration of the light impulse is 1/1000 second.) As of 2003, the majority of cameras targeted for consumer use have an electronic flash unit built in.

Another type of flash unit are microflashes, which are high-voltage flash units discharging a flash of light with an exceptionally quick, sub-microsecond duration. These are commonly used by scientists or engineers for examining extremely fast moving objects or reactions, famous for producing images of bullets tearing through objects like lightbulbs or balloons (see Harold Eugene Edgerton).

Studio flashes usually contain a modeling light, an incandescent lightbulb close to the flash tube. The continuous illumination of a modeling light helps in visualizing the effect of the flash.

The strength of a flash device is often indicated in terms of a guide number, despite the fact that the published guide numbers of different units can not necessarily be directly compared.

Although they are not yet at the power levels to replace xenon flash devices in still cameras, LEDs (specifically, high current flash LEDs) have recently been used as flash sources in camera phones. LEDs are expected to approach the power levels of xenon in the near future and may replace built-in xenon flashes in still cameras. The major advantages of LEDs over xenon include low voltage operation, higher efficiency and extreme miniaturization.

Focal plane shutter synchronization

Electronic flash units have compatibility issues with focal plane shutters. Focal plane shutters expose using two curtains that cross the sensor. The first one opens and then the second curtain follows it after a delay equal to the nominal shutter speed. A typical modern focal plane shutter takes about 1/200s to cross the sensor, so at speeds shorter than this only part of the sensor is uncovered at any one time. Electronic flash can have durations as short as 50 µs, so at speeds above the shutter traverse time only part of the sensor is exposed. This limits the shutter speed to about 1/200s when using flash.

High-end flash units address this problem by offering a mode, typically called FP sync or HSS, which fires the flash tube multiple times during the time the slit traverses the sensor. Such units require communication with the camera and are thus dedicated to a particular camera make. The multiple flashes result in a significant decrease in guide number, since each is only a part of the total flash power, but it's all that illuminates any particular part of the sensor. In general, if s is the shutter speed, and t is the shutter traverse time, the guide number reduces by √ (s / t). For example, if the guide number is 100, and the shutter traverse time is 5 ms (a shutter speed of 1/200s), and the shutter speed is set to 1/2000s (0.5 ms), the guide number reduces by a factor of √ (0.5 / 5), or about 3.16, so the resultant guide number at this speed would be about 32.

In fact, current (2010) flash units frequently have much lower guide numbers in HSS mode than in normal modes, even at speeds below the shutter traverse time. For example, the Mecablitz 58 AF-1 digital flash unit has a guide number of 58 in normal operation, but only 20 in HSS mode, even at low speeds.

Flash

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A flash is a device used in photography producing a flash of artificial light (typically 1/1000 to 1/200 of a second) at a color temperature of about 5500 K to help illuminate a scene. A major purpose of a flash is to illuminate a dark scene. Other uses are capturing quickly moving objects or changing the quality of light. Flash refers either to the flash of light itself or to the electronic flash unit discharging the light. Most flash units as of 2009 are electronic, having evolved from single-use flashbulbs and flammable powders. Modern cameras often activate flash units automatically.

Flash units are commonly built directly into a camera. Some cameras allow separate flash units to be mounted via a standardized "accessory mount" bracket (hot shoe). In professional studio equipement, flashes may be large, standalone units, or studio strobes, powered by special battery packs or connected to mains and synchronized with the camera from either a flash synchronization cable, radio transmitter, or are light-triggered, meaning that only one flash unit needs to be synchronized with the camera, which in turn triggers the other units.

Photographic enlarging lenses

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EL-Nikkor

The EL-Nikkor series of lenses are designed for photographic enlargers. Most feature 39mm Leica thread mounts, although some feature a 50mm screw mount. Most are 6-element, 4-group designs. Some slower, lower-cost designs (marked †) are 4-element, 3-group designs. Newer versions of these lenses are marked with an "N" (focal lengths to 105mm) or "A" (focal lengths from 135mm). (Per Nikon, Inc. Technical and Service Support (800-645-6689), manufacture and sale of all enlarging lenses has been discontinued.)

40mm f/4 EL-Nikkor
50mm f/2.8 EL-Nikkor
50mm f/4 EL-Nikkor†
63mm f/2.8 EL-Nikkor
63mm f/3.5 EL-Nikkor
68mm f/3.5 EL-Nikkor
75mm f/4 EL-Nikkor†
80mm f/5.6 EL-Nikkor

68mm f/3.5 EL-Nikkor
105mm f/5.6 EL-Nikkor
135mm f/5.6 EL-Nikkor
150mm f/5.6 EL-Nikkor
180mm f/5.6 EL-Nikkor
210mm f/5.6 EL-Nikkor
300mm f/5.6 EL-Nikkor

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Lenses for large format photography

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Nikkor-SW

4-group wide-angle lens series, consisting of 6, 7, or 8 elements.
65mm f/4 Nikkor-SW
75mm f/4.5 Nikkor-SW
90mm f/4.5 Nikkor-SW
90mm f/8 Nikkor-SW
120mm f/8 Nikkor-SW
150mm f/8 Nikkor-SW

Nikkor-W

6-element, 4-group series.
100mm f/5.6 Nikkor-W
105mm f/5.6 Nikkor-W
135mm f/5.6 Nikkor-W
150mm f/5.6 Nikkor-W
180mm f/5.6 Nikkor-W
210mm f/5.6 Nikkor-W
240mm f/5.6 Nikkor-W
300mm f/5.6 Nikkor-W
360mm f/6.5 Nikkor-W

Nikkor-M

Compact, 4-element, 3-group series.
105mm f/3.5 Nikkor-M
200mm f/8 Nikkor-M
300mm f/9 Nikkor-M
450mm f/9 Nikkor-M

Nikkor-AM

8-element, 4-group aphochromatic macro series, optimized for 1:1 reproduction.
120mm f/5.6 Nikkor-AM ED
210mm f/5.6 Nikkor-AM ED

Nikkor-T

Telephoto series. The 360 mm / 600 mm are triple-convertible lenses with 500 mm and 720 mm / 800 mm and 1200 mm interchangeable rear elements which are available separately.
270mm f/6.3 Nikkor-T ED
360mm f/8 Nikkor-T ED
500mm f/11 Nikkor-T ED
720mm f/16 Nikkor-T ED
600mm f/9 Nikkor-T ED
800mm f/12 Nikkor-T ED
1200mm f/18 Nikkor-T ED

APO-Nikkor

240mm f/9 APO-Nikkor
4-element, 4-group apochromatic series, designed for the printing industry, optimized for 1:1 reproduction.
240mm f/9 APO-Nikkor
455mm f/9 APO-Nikkor

Fisheye lens

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In photography, a fisheye lens is a wide-angle lens that takes in an extremely wide, hemispherical image. Originally developed for use in meteorology[1] to study cloud formation and called "whole-sky lenses", fisheye lenses quickly became popular in general photography for their unique, distorted appearance. They are often used by photographers shooting broad landscapes to suggest the curve of the Earth. Hemispherical photography is used for various scientific purposes to study plant canopy geometry and to calculate near-ground solar radiation.

The focal lengths of fisheye lenses depend on the film format. For the popular 35 mm film format, typical focal lengths of fisheye lenses are between 8 mm and 10 mm for circular images, and 15–16 mm for full-frame images. For digital cameras using smaller electronic imagers such as 1/4" and 1/3" format CCD or CMOS sensors, the focal length of "miniature" fisheye lenses can be as short as 1 to 2mm.

All the ultra-wide angle lenses suffer from some amount of barrel distortion. While this can easily be corrected for moderately wide angles of view, rectilinear ultra-wide angle lenses with angles of view greater than 90 degrees are difficult to design. Fisheye lenses achieve extremely wide angles of view by forgoing a rectilinear image, opting instead for a special mapping (for example: equisolid angle), which gives images a characteristic convex appearance. A panorama by rotating lens or stitching images (cylindrical perspective) is not a fisheye photo.

Types of fisheye lenses

In a circular fisheye lens, the image circle is inscribed in the film or sensor area; in a full-frame fisheye lens the image circle is circumscribed around the film or sensor area.

Further, different fisheye lenses distort images differently, and the manner of distortion is referred to as their mapping function. A common type for consumer use is equisolid angle.

Circular

The first types of fisheye lenses to be developed were "circular fisheyes" — lenses which took in a 180° hemisphere and projected this as a circle within the film frame. Some circular fisheyes were available in orthographic projection models for scientific applications. These have a 180° vertical angle of view, and the horizontal and diagonal angle of view are also 180°. Most circular fisheye lenses cover a smaller image circle than rectilinear lenses, so the corners of the frame will be completely dark.

Full-frame

As fisheye lenses gained popularity in general photography, camera companies began manufacturing fisheye lenses that enlarged the image circle to cover the entire 35 mm film frame, and this is the type of fisheye most commonly used by photographers.

The picture angle produced by these lenses only measures 180 degrees when measured from corner to corner: these have a 180° diagonal angle of view, while the horizontal and vertical angles of view will be smaller; for an equisolid angle-type 15 mm full-frame fisheye, the horizontal FOV will be 147°, and the vertical FOV will be 94°.

The first full-frame fisheye lens to be mass-produced was a 16 mm lens made by Nikon in the early 1970s. Digital cameras with APS-C sized sensors require a 10.5 mm lens to get the same effect as a 16 mm lens on a camera with full-frame sensor.

Theory of operation

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Most photographic lenses can be thought of as modified pinhole lenses. A pinhole lens would be excellent except for a few serious limitations. They are limited in their resolution because, while geometric optics says that making the pinhole smaller improves resolution, this also reduces the amount of entering light; furthermore, diffraction limits the effectiveness of shrinking the hole. Most photographic lenses can be thought of as an answer to the question "how can we modify a pinhole lens to admit more light and give higher resolution?" A first step is to put a simple convex lens at the pinhole with a focal length equal to the distance to the film plane (assuming the camera will take pictures of distant objects). This allows us to open up the pinhole a bit. The geometry is almost the same as with a simple pinhole lens, but rather than being illuminated by single rays of light, each image point is illuminated by a focused "pencil" of light rays. Standing out in the world, you would see the small hole. This image is known as the entrance pupil: all rays of light leaving an object point that enters this pupil will be focused to the same point on the film. If one were inside the camera, one would see the lens acting as a projector. The image of aperture is the exit pupil.

Photographic lens design

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Number of elements

The complexity of a lens—the number of elements and their degree of asphericity—depends upon the angle of view and the maximum aperture, among other variables including intended price point. An extreme wideangle lens of large aperture must be of very complex construction to correct for optical aberrations, which are worse at the edge of the field and when the edge of a large lens is used for image-forming. A long-focus lens of small aperture can be of very simple construction to attain comparable image quality; a doublet (with two elements) will often suffice. Some older cameras were fitted with "convertible" lenses of normal focal length; the front element could be unscrewed, leaving a lens of twice the focal length and angle of view, and half the aperture. The simpler half-lens was of adequate quality for the narrow angle of view and small relative aperture. Obviously the bellows had to extend to twice the normal length.

Good-quality lenses with maximum aperture no greater than f/2.8 and fixed, normal, focal length need at least three (triplet) or four elements (the trade name "Tessar" derives from the Greek tessera, meaning "four"). The widest-range zooms often have fifteen or more. The reflection of light at each of the many interfaces between different optical media (air, glass, plastic) seriously degraded the contrast and color saturation of early lenses, zoom lenses in particular, especially where the lens was directly illuminated by a light source. The introduction many years ago of optical coatings, and advances in coating technology over the years, have resulted in major improvements, and modern high-quality zoom lenses give images of quite acceptable contrast, although zoom lenses with many elements will transmit less light than lenses made with fewer elements (all other factors such as aperture, focal length, and coatings being equal)

Aperture and focal length

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The two fundamental parameters of an optical lens are the focal length and the maximum aperture. The lens' focal length determines the magnification of the image projected onto the image plane, and the aperture the light intensity of that image. For a given photographic system the focal length determines the angle of view, short focal lengths giving a wider field of view than longer focal length lenses. The wider the aperture, identified by a smaller f-number, allows using a faster shutter speed for the same exposure.

The maximum usable aperture of a lens is specified as the focal ratio or f-number, defined as the lens' focal length divided by the effective aperture (or entrance pupil), a dimensionless number. The lower the f-number, the higher light intensity at the focal plane. Larger apertures (smaller f-numbers) provide a much shallower depth of field than smaller apertures, other conditions being equal. Practical lens assemblies may also contain mechanisms to deal with measuring light, secondary apertures for flare reduction, and mechanisms to hold the aperture open until the instant of exposure to allow SLR cameras to focus with a brighter image with shallower depth of field, theoretically allowing better focus accuracy.

Focal lengths are usually specified in millimetres (mm), but older lenses might be marked in centimetres (cm) or inches. For a given film or sensor size, specified by the length of the diagonal, a lens may be classified as a:
Normal lens: angle of view of the diagonal about 50° and a focal length approximately equal to the image diagonal.
Wide-angle lens: angle of view wider than 60° and focal length shorter than normal.
Telephoto lens or long-focus lens: angle of view narrower and focal length longer than normal. A distinction is sometimes made between a long-focus lens and a true telephoto lens: the telephoto lens has a telephoto group to reduce the physical length of the objective.

Macro lens: special lens corrected optically for close-ups, e.g., for images to object ratios ranging from about 1:10 to 1:1. and having a particularly flat image plane suitable for flat images. A macro lens may be of any focal length, the actual focus length being determined by its practical use, considering magnification the required ratio, access to the subject and illumination considerations.

Construction

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A photographic lens may be made from a number of elements: from one, as in the Box Brownie's meniscus lens, to over 20 in the more complex zooms. These elements may themselves comprise a group of lenses cemented together.

The front element is critical to the performance of the whole assembly. In all modern lenses the surface is coated to reduce abrasion, flare, and surface reflectance, and to adjust color balance. To minimize aberration, the curvature is usually set so that the angle of incidence and the angle of refraction are equal. In a prime lens this is easy, but in a zoom there is always a compromise.

The lens usually is focused by adjusting the distance from the lens assembly to the image plane, or by moving elements of the lens assembly. To improve performance, some lenses have a cam system that adjusts the distance between the groups as the lens is focused. Manufacturers call this different things. Nikon calls it CRC (close range correction), while Hasselblad calls it FLE (floating lens element).

Glass is the most common material used to construct lens elements, due to its good optical properties and resistance to scratching. Other materials are also used, such as quartz glass, fluorite, plastics like acrylic (Plexiglass), and even germanium and meteoritic glass.Plastics allow the manufacturing of strongly aspherical lens elements which are difficult or impossible to manufacture in glass, and which simplify or improve lens manufacturing and performance. Plastics are not used for the outermost elements of all but the cheapest lenses as they scratch easily. Molded plastic lenses have been used for the cheapest disposable cameras for many years, and have acquired a bad reputation: manufacturers of quality optics tend to use euphemisms such as "optical resin". However many modern, high performance (and high priced) lenses from popular manufacturers include molded or hybrid aspherical elements, so it is not true that all lenses with plastic elements are of low photographic quality.

The 1951 USAF resolution test chart is one way to measure the resolving power of a lens. The quality of the material, coatings, and build affect the resolution. Lens resolution is ultimately limited by diffraction, and very few photographic lenses approach this resolution. Ones that do are called "diffraction limited" and are usually extremely expensive.

Today, most lenses are multi-coated in order to minimize lens flare and other unwanted effects. Some lenses have a UV coating to keep out the ultraviolet light that could taint color. Most modern optical cements for bonding glass elements also block UV light, negating the need for a UV filter. UV photographers must go to great lengths to find lenses with no cement or coatings.

A lens will most often have an aperture adjustment mechanism, usually an iris diaphragm, to regulate the amount of light that passes. In early camera models a rotating plate or slider with different sized holes was used. These Waterhouse stops may still be found on modern, specialized lenses. A shutter, to regulate the time during which light may pass, may be incorporated within the lens assembly (for better quality imagery), within the camera, or even, rarely, in front of the lens. Some cameras with leaf shutters in the lens omit the aperture, and the shutter does double duty.

Photographic Lens

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A photographic lens (also known as objective lens or photographic objective) is an optical lens or assembly of lenses used in conjunction with a camera body and mechanism to make images of objects either on photographic film or on other media capable of storing an image chemically or electronically.

While in principle a simple convex lens will suffice, in practice a compound lens made up of a number of optical lens elements is required to correct (as much as possible) the many optical aberrations that arise. Some aberrations will be present in any lens system. It is the job of the lens designer to balance these out and produce a design that is suitable for photographic use and possibly mass production.

There is no major difference in principle between a lens used for a still camera, a video camera, a telescope, a microscope, or other apparatus, but the detailed design and construction are different.

A lens may be permanently fixed to a camera, or it may be interchangeable with lenses of different focal lengths, apertures, and other properties.

Uses of lenses

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A single convex lens mounted in a frame with a handle or stand is a magnifying glass.

Lenses are used as prosthetics for the correction of visual impairments such as myopia, hyperopia, presbyopia, and astigmatism. (See corrective lens, contact lens, eyeglasses.) Most lenses used for other purposes have strict axial symmetry; eyeglass lenses are only approximately symmetric. They are usually shaped to fit in a roughly oval, not circular, frame; the optical centers are placed over the eyeballs; their curvature may not be axially symmetric to correct for astigmatism. Sunglasses' lenses are designed to attenuate light; sunglass lenses that also correct visual impairments can be custom made.

Other uses are in imaging systems such as monoculars, binoculars, telescopes, microscopes, cameras and projectors. Some of these instruments produce a virtual image when applied to the human eye; others produce a real image which can be captured on photographic film or an optical sensor, or can be viewed on a screen. In these devices lenses are sometimes paired up with curved mirrors to make a catadioptric system where the lenses spherical aberration corrects the opposite aberration in the mirror (such as Schmidt and meniscus correctors).

Convex lenses produce an image of an object at infinity at their focus; if the sun is imaged, much of the visible and infrared light incident on the lens is concentrated into the small image. A large lens will create enough intensity to burn a flammable object at the focal point. Since ignition can be achieved even with a poorly made lens, lenses have been used as burning-glasses for at least 2400 years.A modern application is the use of relatively large lenses to concentrate solar energy on relatively small photovoltaic cells, harvesting more energy without the need to use larger, more expensive, cells.

Radio astronomy and radar systems often use dielectric lenses, commonly called a lens antenna to refract electromagnetic radiation into a collector antenna.

Lenses can become scratched and abraded. Abrasion resistant coatings are available to help control this

Types of simple lenses

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Lenses are classified by the curvature of the two optical surfaces. A lens is biconvex (or double convex, or just convex) if both surfaces are convex. If both surfaces have the same radius of curvature, the lens is equiconvex. A lens with two concave surfaces is biconcave (or just concave). If one of the surfaces is flat, the lens is plano-convex or plano-concave depending on the curvature of the other surface. A lens with one convex and one concave side is convex-concave or meniscus. It is this type of lens that is most commonly used in corrective lenses.

If the lens is biconvex or plano-convex, a collimated or parallel beam of light travelling parallel to the lens axis and passing through the lens will be converged (or focused) to a spot on the axis, at a certain distance behind the lens (known as the focal length). In this case, the lens is called a positive or converging lens

Construction of simple lenses

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Most lenses are spherical lenses: their two surfaces are parts of the surfaces of spheres, with the lens axis ideally perpendicular to both surfaces. Each surface can be convex (bulging outwards from the lens), concave (depressed into the lens), or planar (flat). The line joining the centres of the spheres making up the lens surfaces is called the axis of the lens. Typically the lens axis passes through the physical centre of the lens, because of the way they are manufactured. Lenses may be cut or ground after manufacturing to give them a different shape or size. The lens axis may then not pass through the physical centre of the lens.

Toric or sphero-cylindrical lenses have surfaces with two different radii of curvature in two orthogonal planes. They have a different focal power in different meridians. This is a form of deliberate astigmatism.

More complex are aspheric lenses. These are lenses where one or both surfaces have a shape that is neither spherical nor cylindrical. Such lenses can produce images with much less aberration than standard simple lenses.

History of Lenses

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The oldest lens artifact is the Nimrud lens, which is over three thousand years old, dating back to ancient Assyria. David Brewster proposed that it may have been used as a magnifying glass, or as a burning-glass to start fires by concentrating sunlight. Assyrian craftsmen made intricate engravings, and could have used such a lens in their work. Another early reference to magnification dates back to ancient Egyptian hieroglyphs in the 8th century BC, which depict "simple glass meniscal lenses".

The earliest written records of lenses date to Ancient Greece, with Aristophanes' play The Clouds (424 BC) mentioning a burning-glass (a biconvex lens used to focus the sun's rays to produce fire). The writings of Pliny the Elder (23–79) also show that burning-glasses were known to the Roman Empire, and mentions what is arguably the earliest use of a corrective lens: Nero was said to watch the gladiatorial games using an emerald(presumably concave to correct for myopia, though the reference is vague). Both Pliny and Seneca the Younger (3 BC–65) described the magnifying effect of a glass globe filled with water.

The word lens comes from the Latin name of the lentil, because a double-convex lens is lentil-shaped. The genus of the lentil plant is Lens, and the most commonly eaten species is Lens culinaris. The lentil plant also gives its name to a geometric figure.

The Arab physicist and mathematician Ibn Sahl (c.940–c.1000) used what is now known as Snell's law to calculate the shape of lenses.Ibn al-Haytham (965–1038), known in the West as Alhazen, wrote the first major optical treatise, the Book of Optics, which contained the earliest historical proof of a magnifying device, a convex lens forming a magnified image. The book was translated into Latin in the 12th century, and became the standard textbook in the field and influenced many other writers.

Excavations at the Viking harbour town of Fröjel, Gotland, Sweden discovered in 1999 the rock crystal Visby lenses, produced by turning on pole-lathes at Fröjel in the 11th to 12th century, with an imaging quality comparable to that of 1950s aspheric lenses. The Viking lenses concentrate sunlight enough to ignite fires.

Widespread use of lenses did not occur until the use of reading stones in the 11th century and the invention of spectacles, probably in Italy in the 1280s. Scholars have noted that spectacles were invented not long after the translation of al-Haytham's book into Latin, but it is not clear what role, if any, the optical theory of the time played in the discovery.Nicholas of Cusa is believed to have been the first to discover the benefits of concave lenses for the treatment of myopia in 1451.

The Abbe sine condition, due to Ernst Abbe (1860s), is a condition that must be fulfilled by a lens or other optical system in order for it to produce sharp images of off-axis as well as on-axis objects. It revolutionized the design of optical instruments such as microscopes, and helped to establish the Carl Zeiss company as a leading supplier of optical instruments.

Nikon d5000 review

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Sensor 23.6 x 15.8 mm Nikon DX format RGB CMOS sensor, 1.5 × FOV crop
Maximum resolution 4,288 × 2,848 (12.3 effective megapixels)
Lens type Interchangeable, Nikon F-mount
Shutter Electronically-controlled vertical-travel focal-plane shutter
Shutter speed range 30 s to 1/4000 s in 1/2 or 1/3 stops and Bulb, 1/200 s X-sync
Exposure metering TTL 3D Color Matrix Metering II metering with a 420 pixel RGB sensor
Exposure modes Auto modes (auto, auto [flash off]), Advanced Scene Modes (Portrait, Landscape, Sports, Close-up, Night Portrait), programmed auto with flexible program (P), shutter-priority auto (S), aperture-priority auto (A), manual (M), (Q) quiet mode.
Metering modes 3D Color Matrix Metering II, Center-weighted and Spot
Focus areas 11-area AF system, Multi-CAM 1000 AF Sensor Module
Focus modes Instant single-servo (AF-S); continuous-servo (AF-C); auto AF-S/AF-C selection (AF-A); manual (M)
Continuous shooting 4 fps for 67 Large Fine JPEG or 11 RAW frames
Viewfinder Optical 0.78x, 95% Pentamirror
ASA/ISO range 200 - 3200 in 1/3 EV steps, up to 6400 as high-boost, as low as 100 low-boost
Flash Built in Pop-up, Guide number 13m at ISO 100, Standard ISO hotshoe, Compatible with the Nikon Creative Lighting System
Flash bracketing 2 or 3 frames in steps of 1/3, 1/2, 2/3, 1 or 2 EV
Custom WB Auto, Incandescent, Fluorescent, Sunlight, Flash, Cloudy, Shade, Kelvin temperature, Preset
Rear LCD monitor 2.7-inch tilt and swivel 320x240 pixel (QVGA) TFT-LCD
Storage Secure Digital, SDHC compatible
Battery Nikon EN-EL9a Lithium-Ion battery
Weight Approx. 560 g (1 lb. 6 oz.) without battery, memory card or body cap

Nikon D3000 review

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Sensor 23.6 x 15.8 mm Nikon DX format RGB CCD sensor, 1.5 × FOV crop
Maximum resolution 3,872 × 2,592 (10.2 effective megapixels)
Lens type Interchangeable, Nikon F-mount
Shutter Electronically-controlled vertical-travel focal-plane shutter
Shutter speed range 30 s to 1/4000 s in 1/2 or 1/3 stops and Bulb, 1/200 s X-sync
Exposure metering TTL 3D Color Matrix Metering II metering with a 420 pixel RGB sensor
Exposure modes Auto modes (auto, auto [flash off]), Guide Mode, Advanced Scene Modes (Portrait, Landscape, Sports, Close-up, Night Portrait), programmed auto with flexible program (P), shutter-priority auto (S), aperture-priority auto (A), manual (M), (Q) quiet mode.
Metering modes 3D Color Matrix Metering II, Center-weighted and Spot
Focus areas 11-area AF system, Multi-CAM 1000 AF Sensor Module
Focus modes Instant single-servo (AF-S); continuous-servo (AF-C); auto AF-S/AF-C selection (AF-A); manual (M)
Continuous shooting 3 fps
Viewfinder Optical 0.80x, 95% Pentamirror
ASA/ISO range 100 - 1600 in 1/3 EV steps, up to 3200 as high-boost
Flash Built in Pop-up, Guide number 13m at ISO 100, Standard ISO hotshoe, Compatible with the Nikon Creative Lighting System
Flash bracketing 2 or 3 frames in steps of 1/3, 1/2, 2/3, 1 or 2 EV
Custom WB Auto, Incandescent, Fluorescent, Sunlight, Flash, Cloudy, Shade, Kelvin temperature, Preset
Rear LCD monitor 3.0-inch 320x240 pixel (QVGA) TFT-LCD
Storage Secure Digital, SDHC compatible
Battery Nikon EN-EL9a rechargeable Lithium-Ion battery
Weight Approx. 485 g without battery, memory card or body cap

Nikon D50 review

2010-07-04T23:32:00.002+03:00

Digital SLR's are quickly becoming the fastest moving segment of the digital camera market, this means more new digital SLR's, more competition and lower prices. The Nikon D50 is introduced as a more affordable and easier to use version of the D70 which was released just under fifteen months ago. Anyone who has seen or handled the D70 will immediately see a strong resemblance in the D50, it's only when you start to examine the camera in a little more detail that you notice the differences (we've detailed them below). Clearly the D50 is designed to compete with other affordable digital SLR's such as the Canon EOS 350D (Digital Rebel XT), Pentax *ist DS and Olympus E-300.
Differences between D50 and D70/D70s

Although quite similar in use and appearance there are some noteworthy differences between the D50 and D70, we have detailed all of the feature / specification differences in the table below. To summarize the most important; the D50 has improved auto focus especially in the area of motion tracking, it has a new auto AF mode (which automatically switches between single and continuous AF depending on the subject), it has a lower resolution metering sensor but that sensor is a newer generation than the one used in the D70 (and D70s) - spot metering circle is also larger, the maximum shutter speed is 1/4000 sec, continuous shooting is 2.5 fps, it has a better viewfinder eyecup, the LCD monitor has increased to 2.0" in size, the D50 takes SD cards (not CF), it's slightly smaller and lighter than the D70 and several features have been removed or simplified to make the camera easier to use.

6MP, same as D70 and D70s. 3,008 x 2,000, also 2,256 x 1,496 and 1,504 x 1,000 pixel settings. Oddly the medium setting is just a few pixels different from the medium setting of the D70 and D70s. Everything else is identical.

AF Sensors: Five, just like D70, D70s, D1X, F5 etc. Same CAM-900 module and -1 EV rating as D70 and D70s.

AF modes: Same as D70 and D70s and adds a new AF-A mode. The AF-A mode automatically selects between AF-S (normal AF) and AF-C (continuous AF). You still have to use the menus to select between AF-S, AF-A and AF-C; the front switch only selects between AF and MF.

Metering: 420 segment color 3D matrix, center-weighted and spot. Rated down to LV 0, same as D70 and D70s. So long as you have at least five segments you're fine, so I wouldn't worry about "only" 420 segments compared to the 1,005 of the more expensive cameras.

Exposure Modes: P, S, A, M and scene modes. Same as D70 and D70s with the one exception of replacing the night landscape mode with a child mode. It does have the night portrait and all the other scene modes of the D70 and D70s. I've never used any of the scene modes anyway.

Pentamirror finder. Same as D70s. D70 had either this or a glass prism depending on where you read it. It looks the same as my D70.

Shutter: Mechanical and electronic like the D70 and D70s. B, 30 - 1/4,000. The manual says 1/2 and 1/3 stops, I forget if the D70 can go in half stops or just thirds. No big deal. Time exposures to 30 minutes with ML-L3 wireless remote.

Frame Rate: 2.5 FPS. Just a little slower than the D70's 3 FPS. It has a buffer, however its depth is unspecified. With the right card it is specified to run for 137 frames continuously till it overflows. The illustration in the manual shows "12," which is the same as the D70 and D70s in the default normal, large JPG setting. I don't know if it's the same or not.

Flash Sync: 1/500, same as D70 and D70s and better than just about every other DSLR regardless of price. It's better than anything from Canon, better than the $5,000 D2X, better than the $3,500 D2H and better than the newest $1,700 D200.

Flash: Built-in, i-TTL, GN 15/49 (m/ft @ ISO 200; 11/36 @ ISO 100), same as D70s. Same numerous and excellent sync modes as D70 and D70s. (Note to Nikon: typo has "TTL" spelt as "TLL" on page 99 of manual, last paragraph.) No ability to use built-in flash as commander for remote control of other flashes.

CCD Sensor: Standard DX size (23.7 x 15.6 mm) and 1.5x mag factor.

ISO: 200 - 1,600, same as D70 and D70s. Adjusts in full stops, not thirds, which I prefer.

White Balance: same fixed settings and white card preset setting as D70 and D70s but lacks direct fine-tuning. The lack of direct WB fine-tuning won't be noticed by 99% of the people who buy these. You can have this through WB bracketing, in which case the camera records three different JPGs as processed from each actual shot. Clever!

Color modes: Three; same as D70 and D70s.

Saturation control: Three settings, same as D70 and D70s.

Histogram: Still the same useless one-channel display (not RGB), just like the D70, D100, D70s, D1x, etc. Nikon's manual even cautions that it's useless and won't agree with what you see in Photoshop (page 53).

Image Rotation: Automatic just like D70 and D70s.

Custom functions: 20 compared to the 25 of the D70s and D70.

File Formats: same as D70: JPEG FINE, NORMAL and BASIC; RAW and RAW + JPEG. Files sizes in the D50 manual are identical to the file sizes I get from my D70.

Memory: SD cards, the little ones, not CF as every other Nikon DSLR has used. Instead of jamming in from the back they slide in from the side. Nikon prints a list of recommended cards, which includes Sandisk, Toshiba and Panasonic. Lexar is prominently absent. Nikon extensively tests every function of the D50 with each of the cards they suggest and guarantees the camera's performance with them. Nikon does not recommend using any other cards and doesn't guarantee anything if you use them. This is great; most camera makers just leave you out on your own here.

LCD (color picture): 2.0;" bigger than D70's 1.8" and identical to the one on the D70s: 130,000 dots.

LCD: (numeric display on top of camera): identical to the one on the D70 and D70s, except no illumination. I work in the dark and use this illumination now and then, so I'd miss this. Most people probably wouldn't.

Battery: EN-EL3, 1,400 mAh, same as D70 and D100. (D70s gets a compatible EN-EL3a of 1,500 mAh) The D50 is rated for 2,000 shots no flash and 400 shots with full power flash every other shot, exactly the same as the D70. Cannot use the MS-D70 holder for three CR2 disposable batteries as the D70 and D70s can.

Size: 5.2 x 4.0 x 3.0" (133 x 102 x 76 mm)

Weight: 19 oz. (540 g) stripped without battery, monitor cover, lens, body cap, strap or memory card.

NIkon D3X review

2010-07-04T22:52:00.002+03:00

Ever since the simultaneous announcement of the Nikon D1H and D1X back in 2001 Nikon's professional D 'single digit' series has been split into two - the X series designed for high resolution applications such as fashion or landscape photography and the H series for high speed sports type photography (lower resolution but faster continuous shooting). When the Nikon D3 was announced in August 2007 it did not carry an 'H' in its name but was clearly designed for speed. So the question wasn't if, but when, Nikon would launch a high-resolution counterpart. It arrived, after more than a year of eager anticipation, in the shape of the Nikon D3X in December 2008.

Superficially, the new flagship is the D3's identical twin. The body, controls, user interface and also a large proportion of the camera's electronic and mechanical innards have been carried over directly from the D3. The camera's core component, however, is brand new. The 36 x 23.9 mm CMOS sensor provides a resolution of 24.5 megapixels, and while this is - compared to the D3 - a massive jump in resolution, D3X users have to accept a smaller range of sensitivity (ISO 100 to 1600, extendable to ISO 50 to 6400) and slower continuous shooting of five frames per second (7 fps in DX mode) in return.

While the only other piece of news - the 'Extra High' setting for Active D-Lighting - won't make much difference for most users, the premium that Nikon is charging for the extra resolution most certainly will. For $8000 retail price you can bag yourself almost two D3s. The D3X is also roughly $1500 more expensive than its only real competitor in terms of specification and features, the Canon EOS 1Ds Mark III. This won't make the professionals who this cameras is targeted at contemplate changing systems, but can a camera be worth the equivalent amount of a small car? Read on and find out in our in-depth review of the Nikon D3X.

24.5 megapixel Full-Frame (36 x 24 mm) sensor
ISO 100 - 1600 (ISO 50 - 6400 in Boost mode)
Also supports DX lenses, viewfinder automatically masks (10.5 megapixels with DX lens)
14-bit A/D conversion, 12 channel readout
Gapless micro lens array and on-chip noise reduction
Nikon EXPEED image processor (Capture NX processing and NR algorithms, optimized for D3X, lower power)
Super fast operation (power-up 12 ms, shutter lag 41 ms, black-out 74 ms)
Kevlar / carbon fibre composite shutter with 300,000 exposure durability
Multi-CAM3500FX Auto Focus sensor (51-point, 15 cross-type, more vertical coverage)
Auto-focus tracking by color (using information from 1005-pixel AE sensor)
Auto-focus calibration (fine-tuning) available (fixed body or up to 20 separate lens settings)
Scene Recognition System (uses AE sensor, AF sensor)
Seven frames per second in continuous and DX mode
Dual Compact Flash card slots (overflow, back-up, RAW on 1 / JPEG on 2, copy)
Compact Flash UDMA support
3.0" 922,000 pixel LCD monitor
Live View with either phase detect (mirror up/down) or contrast detect Auto Focus
Virtual horizon indicates if camera is level (like an aircraft cockpit display)
HDMI HD video output
'Active D-Lighting' with new 'Extra High' setting (adjusts metering as well as applying D-Lighting curve)
Detailed 'Control Panel' type display on LCD monitor, changes color in darkness
Buttons sealed against moisture
Dual battery charger as standard

Nikon D3 review

2010-07-04T22:37:00.002+03:00

The professional Nikon D 'single digit' series of digital SLR's started life back in June 1999 with the groundbreaking D1. Groundbreaking because it was the digital SLR that broke Kodak's stranglehold on the digital SLR market and fundamentally brought prices down to a level which most professionals could afford (around the US$5,500 mark). Since then we have seen a steady progression in the evolution of this line of cameras. Whilst the core values of a high quality full-size body with integrated grip have remained constant, the line split into two halves (indicated by the X and H suffixes), one targeted at high resolution photography the other high speed sports type photography (lower resolution but faster continuous shooting). It's been almost three years since Nikon introduced a completely new digital SLR with a new sensor (the D2X) and there had been much anticipation that Nikon's next move would be a full-frame chip.

And so it was, with the introduction last August of the new 'FX format' D3, featuring a 36 x 23.9 mm 12.1 megapixel CMOS sensor as well as a vast array of new features which absolutely raise it another notch above previous single digit Nikon DSLRs. Important headline improvements include high sensitivity support by default, up to ISO 6400 with 25600 available as a boost option, 14-bit A/D conversion, a new standard image processor, a new shutter, new auto focus sensor, focus tracking by color, nine frames per second continuous, dual compact flash support, DX lens support (albeit at lower resolution) with automatic cropping and a 3.0" 922,000 pixel LCD monitor (which it has to be said is lovely).

Some will undoubtedly question Nikon for 'only' delivering twelve megapixels on their first full frame digital SLR, all we can presume by looking at past model line history is that this camera is designed for speed (both in sensitivity, auto-focus and continuous shooting). Our first comment on seeing the D3 in the late summer of last year was 'where's the 'H' suffix?', something echoed many times in the months following announcement by commentators and photographers. Although Nikon remains tight-lipped about its future plans it seems fair to assume that Photokina will bring an EOS 1DS Mark III competitor (with higher resolution but without the high speed shooting)

First ever Nikon DSLR with a Full-Frame (36 x 24 mm) sensor (dubbed the 'FX' format)
12.1 megapixel full-frame sensor (8.45µm pixel pitch)
ISO 200 - 6400 (with boost up to ISO 25600)
Also supports DX lenses, viewfinder automatically masks (5.1 megapixels with DX lens)
5:4 ratio crop mode (10 megapixels, up to 9 fps, viewfinder masked)
14-bit A/D conversion, 12 channel readout
Nikon EXPEED image processor (Capture NX processing and NR algorithms, lower power)
Super fast operation (power-up 12 ms, shutter lag 41 ms, black-out 74 ms)
New Kevlar / carbon fibre composite shutter with 300,000 exposure durability
New Multi-CAM3500FX Auto Focus sensor (51-point, 15 cross-type, more vertical coverage)
Auto-focus tracking by color (using information from 1005-pixel AE sensor)
Auto-focus calibration (fine-tuning) now available (fixed body or up to 20 separate lens settings)
Scene Recognition System (uses AE sensor, AF sensor)
Picture Control image parameter presets (replace Color Modes I, II and III)
Custom image parameters now support brightness as well as contrast
Nine frames per second continuous with auto-focus tracking
Eleven frames per second continuous without auto-focus tracking
Ten / eleven frames per second continuous in DX-crop mode (AF / no-AF)
Dual Compact Flash card slots (overflow, back-up, RAW on 1 / JPEG on 2, copy)
Compact Flash UDMA support
3.0" 922,000 pixel LCD monitor
Live View with either phase detect (mirror up/down) or contrast detect Auto Focus
Virtual horizon indicates if camera is level (like an aircraft cockpit display)
HDMI HD video output
'Active D-Lighting' (adjusts metering as well as applying D-Lighting curve)
Detailed 'Control Panel' type display on LCD monitor, changes color in darkness
Buttons sealed against moisture
Dual battery charger as standard

Nikon D700 review

2010-07-04T14:24:00.006+03:00

Max resolution 4256 x 2832
Low resolution 3184 x 2120, 2128 x 1416
Image ratio w:h 3:2
Effective pixels 12.1 million
Sensor photo detectors 12.9 million
Sensor size 36 x 24 mm (8.64 cm²)
Pixel density 1.4 MP/cm²
Sensor type CMOS
Sensor manufacturer Unknown
ISO rating 200 - 6400 in 1, 1/2 or 1/3 EV steps (100 - 25600 with boost)
Zoom wide (W)
Zoom tele (T)
Digital zoom No
Image stabilization No
Auto Focus Nikon Multi-CAM3500 FX
Manual Focus Yes
Normal focus range
Macro focus range
White balance override 12 positions, plus manual and Kelvin
Aperture range
Min shutter 30 sec
Max shutter 1/8000 sec
Built-in Flash Yes, pop-up
Flash range
External flash Yes, hot-shoe plus sync connector
Flash modes Front curtain, Rear curtain, Red-Eye, Slow, Red-Eye Slow
Exposure compensation -5 to +5 EV in 1/2 or 1/3 EV steps
Metering 3D Matrix metering II, Center weighted, Spot
Aperture priority Yes
Shutter priority Yes
Focal length multiplier 1
Lens thread Nikkor AF / F-mount, D-Type
Continuous Drive Yes, 5 fps @ 12 mp, 8 fps @ 12 mp (with battery pack)
Movie Clips No
Remote control Yes
Self-timer Yes, 2 to 20 sec
Timelapse recording Yes
Orientation sensor Yes
Storage types Compact Flash (Type I)
Storage included None
Uncompressed format Yes, RAW, TIFF
Quality Levels Fine, Normal, Basic
Viewfinder Optical (Pentaprism, 95% coverage, 0.72x magnification)
LCD 3 "
LCD Dots 922,000
Live View Yes
USB USB 2.0 (480Mbit/sec)
HDMI Yes
Wireless No
GPS No
Environmentally sealed Yes
Battery Nikon EN-EL3e Lithium-Ion battery
Weight (inc. batteries) 1074 g (37.9 oz)
Dimensions 147 x 123 x 77 mm (5.8 x 4.8 x 3 in)

Nikon d300 vs Nikon d300s

2010-06-27T21:48:00.003+03:00

No picture available

Nikon updated one of the most well-received digital SLRs on the market with the Nikon D300S, a digital SLR with the same 12.3-megapixel sensor, a slightly faster frame rate, and HD Video capture capability, among other improvements, all for the same price.

In August 2007, Nikon launched the D300, which offered 12.3-megapixel resolution from a DX format image sensor roughly equal in size to a frame of APS-C film. Sensitivity could be extended as high as ISO 6,400 equivalent, and the Nikon D300 featured a weather-sealed body, 100% viewfinder coverage, a 920,000-dot LCD display with live-view capability, plus six frames-per-second burst shooting. The Nikon D300's feature set was robust enough not only to serve the enthusiastic amateur photographer, but also to prove attractive to pros looking for an extra camera body without breaking the bank.

Two years down the road, Nikon refreshed the D300 design with the Nikon D300S, incorporating almost the entire feature set of the previous camera plus several must-have features to compete with the latest cameras.

D300S vs D300 Differences:
1280 x 720p HD video recording at 24 fps
Built-in mono microphone with adjustable gain
External 3.5mm stereo mic jack
Contrast-detect AF during videos
7 fps vs 6 fps top burst speed (8 fps for both with battery grip)
Slightly faster AF performance
Dual CF Type I and SD card slots vs single CF Type I/II
Wider built-in flash coverage (16mm vs 18mm)
Dedicated Live View button
Dedicated Info button
Multi-selector center button
Quiet shutter release mode
Sliding memory card door vs locking swing type
Mini HDMI Type-C vs Type-A connector
Composite A/V output vs composite video only output
Virtual horizon display
Optional framing grid in Live View mode
Icon bar menu below Shooting Info display for quick access to some settings
Extra-high and Auto Active D-Lighting settings
Active D-Lighting bracketing
Face detection during playback
In-camera RAW processing and image resizing
In-camera movie trimming
72-image thumbnail view in playback mode
Battery life CIPA rated at 950 shots per charge vs 1,000
Other minor changes

Nikon D90 overview

2010-06-27T21:28:00.003+03:00

Nikon has been cranking out new digital SLR camera upgrades like crazy these last two years, with the low, high, and pro end of the lineup getting update after update, but the mid-level SLR in particular has gone more than 18 months without an upgrade. While the Nikon D80 has a rich feature-set and maintained a high resale value throughout its tenure, it's due for an upgrade.

Though it's late to the party, the Nikon D90 arrives fashionably, just as its predecessor did in late 2006. It comes sauntering in with most of the current hot features that the D80 lacked, plus a new twist that will bowl them all over with its relevance and utility.

With a 12.3-megapixel sensor, the Nikon D90 rises to the resolution of the more professional D300. It also shares the same sensitivity as the D300, ranging from ISO 200 to 3,200, plus L1 (100) and H1 (6,400).

Another essential upgrade on the Nikon D90 is the move to a high resolution 3-inch LCD screen. The 920,000-pixel display has a 170-degree viewing angle and appears to be as nice as the new screens found on the D3 and D300. It makes checking focus and using Live view mode that much more pleasant.

New to the intermediate range for Nikon, the Live View feature offers some new tricks over the mode found on the Nikon D90's high-end predecessors, particularly including Face Detection. Surprisingly, there is no phase-detect autofocus available on the Nikon D90 when in Live view mode, only three contrast-detect modes: Face Priority, Wide Area, and Normal Area. Just as we've seen on consumer cameras, in Face Detection mode, a box surrounds detected faces and follows them around the screen. The Nikon D90 can track up to five faces. Live view is activated with a dedicated button just right of the LCD.

Though Face Detection is helpful in Live view mode, its utility goes further, as it's now an integral part of Nikon's Scene Recognition System (SRS). Thanks to the Nikon D90's 420-pixel matrix metering sensor, the SRS can combine color metering with autofocus sensor data and tune white balance and exposure with a particular bias toward getting faces exposed properly. In theory, this should also include making sure the Nikon D90 focuses on an eye rather than a nose or forehead. If true in practice, this is quite an advance. Face detection even comes into play in i-TTL Flash control.

The Nikon D90's 11-point phase-detect AF system is arrayed in a diamond pattern and now includes 3D focus tracking as found on the D3 and D300.

Since the dawn of Live view on SLRs, the obvious question has been, "Why no movie mode? If you can draw a live image off the sensor, why can't you record it?" Nikon is the first to answer the question with a resounding, "You can!" The Nikon D90 records movies as a Motion JPEG in AVI format at 24 frames per second at what they're calling "720p equivalent" resolution: 1,280 x 720. Other resolutions include 640 x 424, and 320 x 216. Though you have to focus manually, and aperture remains fixed during recording, audio for the videos is captured through the monaural mic on the camera.

A new lens will ship with the Nikon D90 kit, as well: the Nikkor 18-105mm f/3.5-5.6 ED VR, with one extra-low dispersion element and one hybrid aspheric element to improve image quality.

Resolution: 12.30 Megapixels
Kit Lens: 5.80x zoom
18-105mm
(27-158mm eq.)
Viewfinder: Optical / LCD
LCD Size: 3.0 inch
ISO: 100-6400
Shutter: 30-1/4000
Max Aperture: 3.5
Mem Type: SD / SDHC
Battery: Custom LiIon
Dimensions: 5.2 x 4.1 x 3.0 in.
(132 x 103 x 77 mm)
Weight: 25.2 oz (713 g)
includes batteries

Nikon D80 overview

2010-06-27T01:42:00.002+03:00

The Nikon D80 combination of high-end features and its 18-135mm DX kit lens make a killer photographic tool for the amateur and intermediate photographer who can't afford or justify the extra cost of the Nikon D200.

While it is very similar to its predecessor, the Nikon D70s, and sports the higher 10.2 megapixel resolution of the D200, the Nikon D80 is replete with new features and advances in overall quality that make it a great upgrade for D50 and D70 owners, plus a compelling "other choice" for those who've been looking at (or waiting for) a Nikon D200. Finally, because its controls are so similar to the D2X and D200, pro photographers may want to pick up a D80 as a second or third body to take along instead of their heavier pro cameras.

Resolution: 10.20 Megapixels
Kit Lens: 7.50x zoom
18-135mm
(27-203mm eq.)
Viewfinder: Optical
LCD Size: 2.5 inch
ISO: 100-3200
Shutter: 30-1/4000
Max Aperture: 3.5
Mem Type: SD / SDHC
Battery: Custom LiIon
Dimensions: 5.2 x 4.1 x 3.0 in.
(132 x 103 x 77 mm)
Weight: 20.6 oz (585 g)

Nikon d60 overview

2010-06-27T01:35:00.002+03:00

The Nikon D60 has a sensor resolution of 10.2 megapixels, and offers ISO sensitivity ranging from 100 to 1,600, with the ability to extend this to ISO 3,200 using the Hi-1 setting. In many respects, the D60 is a clone of the preceding D40x model. As we'll see though, the Nikon engineers have added a number of new features and enhancements. The combination probably isn't enough to entice D40x owners to upgrade, but owners of the 6-megapixel D40 might want to, and the Nikon D60 makes a really excellent entry-level model for those just making the move to an SLR. Even for established photographers, the D60 is a pleasure to use, making a great second (or even first) body.

The Nikon D60 has a 2.5" LCD display with 230,000 pixel resolution and a 170 degree viewing angle, which means your friends can gather 'round behind you and everyone will see the same image quality wherever they're standing. Other D60 features include extensive (and newly expanded) in-camera image editing, a full array of automatic and manual exposure modes, including some modes tuned for specific situations, like Portrait, Landscape, Child, Sports, Close up and Night portrait. There's an Auto ISO mode that lets the user select the maximum ISO and minimum shutter speed, which leaves you with some control over what Auto can do. Like the D40 and D40x before it, autofocus is only supported when using AF-S or AF-I lenses, which limits you to newer Nikon lenses. The built-in i-TTL flash has a guide number of 12m /39 ft. at ISO 100 in auto modes and 13m / 42 ft. in manual. Maximum flash sync is 1/200 second.

The Nikon D60 uses an EN-EL9 lithium-ion rechargeable battery, with a rated 500 shots per charge, and stores images on SD/SDHC memory cards (not included). Connectivity includes USB 2.0 high-speed, A/V out, and the option of an infrared remote

Resolution: 10.20 Megapixels
Kit Lens: 3.00x zoom 18-55mm (27-83mm eq.)
Viewfinder: Optical
LCD Size: 2.5 inch
ISO: 100-3200
Shutter: 30-1/4000
Max Aperture: 3.5
Mem Type: SD / SDHC
Battery: Custom LiIon
Dimensions: 5.0 x 3.7 x 2.5 in. (126 x 94 x 64 mm)
Weight: 19.2 oz (544 g) includes batteries