The focal length of an optical system is a measure of how the system converges or diverges light. For an optical system in air, it is the distance over which collimated rays are brought to a focus. A system with a shorter focal length has greater optical power than one with a long focal length. In most photography and all telescopy, where the subject is infinitely far away, longer focal length leads to higher magnification and a narrower angle of view. On the other hand, in applications such as microscopy in which magnification is achieved by bringing the object close to the lens, a shorter focal length leads to higher magnification because the subject can be brought closer to the center of projection. For a thin lens in air, the focal length is the distance from the center of the lens to the principal foci of the lens. For a converging lens, the focal length is positive, is the distance at which a beam of collimated light will be focused to a single spot. For a diverging lens, the focal length is negative, is the distance to the point from which a collimated beam appears to be diverging after passing through the lens.
When a lens is used to form an image of some object, the distance from the object to the lens u, the distance from the lens to the image v, the focal length f are related by 1 f = 1 u + 1 v. The focal length of a thin lens can be measured by using it to form an image of a distant light source on a screen; the lens is moved. In this case 1/u is negligible, the focal length is given by f ≈ v. For a thick lens, or an imaging system consisting of several lenses or mirrors, the focal length is called the effective focal length, to distinguish it from other used parameters: Front focal length or front focal distance is the distance from the front focal point of the system to the vertex of the first optical surface. Back focal length or back focal distance is the distance from the vertex of the last optical surface of the system to the rear focal point. For an optical system in air, the effective focal length gives the distance from the front and rear principal planes to the corresponding focal points.
If the surrounding medium is not air the distance is multiplied by the refractive index of the medium. Some authors call these distances the front/rear focal lengths, distinguishing them from the front/rear focal distances, defined above. In general, the focal length or EFL is the value that describes the ability of the optical system to focus light, is the value used to calculate the magnification of the system; the other parameters are used in determining where an image will be formed for a given object position. For the case of a lens of thickness d in air, surfaces with radii of curvature R1 and R2, the effective focal length f is given by the Lensmaker's equation: 1 f =, where n is the refractive index of the lens medium; the quantity 1/f is known as the optical power of the lens. The corresponding front focal distance is: FFD = f, the back focal distance: BFD = f. In the sign convention used here, the value of R1 will be positive if the first lens surface is convex, negative if it is concave.
The value of R2 is negative if the second surface is convex, positive if concave. Note that sign conventions vary between different authors, which results in different forms of these equations depending on the convention used. For a spherically curved mirror in air, the magnitude of the focal length is equal to the radius of curvature of the mirror divided by two; the focal length is positive for a concave mi
The Leica L-Mount is a bayonet mount developed by Leica Camera AG for interchangeable-lens autofocus digital cameras. The L-Mount has a flange depth of 20.0 mm. The L-mount exists in an APS-C version and a full-frame version; the two versions are electronically compatible. TL lenses mounted on full-frame cameras will cause the camera to use a crop mode from the center of the sensor, corresponding to the APS-C coverage of the lens. SL lenses mounted on TL cameras function providing a 1.5x crop field of view, as is typical with APS-C cameras. In 2018 Leica formed the L-Mount Alliance, licensing Sigma and Panasonic to use an upgraded version of the mount for their own products, opening the way for a more extensive system of compatible cameras and lenses, it was introduced in April 2014 with the Leica T camera. At the time of introduction, it was called the "T-mount", but this was changed to "L-mount" with the release of the Leica SL, a full-frame sensor camera using the same mount; the Leica T was renamed to the Leica TL at this time, to permit marketing clarity for the L-mount lens line: TL lenses would cover APS-C sensors, while SL lenses would cover full-frame sensors.
The mount is used by the Leica TL, TL2, Leica Leica SL systems. The L-Mount is a registered trademark of Leica Camera AG. On 25 September 2018, the L-Mount Alliance between Leica and Sigma was announced, enabling the partners "to make use of the L-Mount standard developed by Leica for their own developments and to offer both cameras and lenses utilising this lens mount" with full compatibility between the three companies' products. According to Sigma CEO, Kazuto Yamaki, the "L-mount system is not the same as the existing one. We updated it a little bit to work better with such lenses through lens adapters."On the same day, Panasonic announced its S1R and S1 full-frame L-Mount cameras and three L-Mount lenses, with seven more lenses to be launched by 2020. Sigma announced that it will launch a full-frame camera in 2019, using the L-Mount and the company's Foveon sensor, as well as a range of L-mount lenses and adapters for Sigma SA and Canon EF lenses. Six cameras and 39 native lenses are confirmed for the L-Mount by 2020.
Leica T/TL cameras use APS-C sensors. The TL mount version is not dust- or splashproof. Leica T Leica TL Leica TL2 Leica CL Leica SL cameras use full-frame sensors; the SL version is dust- and splashproof. Leica SL Panasonic S1R Panasonic S1 Unspecified Foveon-based full-frame Sigma Leica has an existing range of fifteen L-Mount lenses. Panasonic committed to releasing a total of ten lenses for the L-mount by the end of 2020, beginning with the 50mm F/1.4 prime and the two zooms listed below. Sigma plans to release a wide range of lenses. 14 primes from Sigma's'Global Vision' range designed for reflex cameras with short flange depths and available for the mirrorless Sony E-mount, will be released in L-Mount from 2019. These will be followed by a range designed for mirrorless parameters. Leica APO-Macro-Elmarit-TL 1:2.8 / 60 ASPH Leica Summilux-TL 1:1.4 / 35 ASPH Leica Summicron-TL 1:2 / 23 ASPH Leica Elmarit-TL 1:2.8 / 18 ASPH Sigma 16mm f/1.4 DC DN Contemporary Sigma 30mm f/1.4 DC DN Contemporary Sigma 56mm f/1.4 DC DN Contemporary Leica Super-Vario-Elmar-TL 1:3.5-4.5 / 11-23 ASPH Leica Vario-Elmar-TL 1:3.5-5.6 / 18-56 ASPH Leica APO-Vario-Elmar-TL 1:3.5-4.5 / 55-135 ASPH Leica Summilux-SL 1:1.4 / 50 ASPH Leica APO-Summicron-SL 1:2 / 75 ASPH Leica APO-Summicron-SL 1:2 / 90 ASPH Leica APO-Summicron-SL 1:2 / 35 ASPH Leica APO-Summicron-SL 1:2 / 50 ASPH Panasonic LUMIX S PRO 50mm f/1.4 Sigma 14mm f/1.8 DG HSM Art Sigma 20mm f/1.4 DG HSM Art Sigma 24mm f/1.4 DG HSM Art Sigma 28mm f/1.4 DG HSM Art Sigma 35mm f/1.4 DG HSM Art Sigma 40mm f/1.4 DG HSM Art Sigma 50mm f/1.4 DG HSM Art Sigma 70mm f/2.8 DG MACRO Art Sigma 85mm f/1.4 DG HSM Art Sigma 105mm f/1.4 DG HSM Art Sigma 135mm f/1.8 DG HSM Art Leica Vario-Elmarit-SL 1:2.8-4 / 24-90 ASPH Leica APO-Vario-Elmarit-SL 1:2.8-4 / 90-280 Leica Super-Vario-Elmar-SL 1:3.5-4.5 / 16-35 ASPH Panasonic LUMIX S 24-105mm f/4 MACRO O.
I. S Panasonic LUMIX S PRO 70-200mm f/4 O. I. S Manual third-party lenses are being produced in L-mount by 7Artisans, Meyer-Optik, Kipon HandeVision. Leica R-Adapter L Leica S-Adapter L Leica M-Adapter L Leica PL-Adapter L Novoflex SL-EOS Adapter Novoflex SL/NIK Adapter Sigma SA-L adapter Sigma EF-L adapter Sigma-manufactured'Global Vision' EF-mount lenses are supported and compatible.
A D-mount is a type of lens mount found on 8mm movie cameras. Throat or thread diameter 15.88 mm Mount thread pitch 32 TPI Flange focal distance 12.29 mm D-Mount lenses have found new uses in the Nikon 1 series and the Pentax Q series cameras. T-mount Lens mount Pentax K mount C-mount PL-mount
A lens mount is an interface – mechanical and also electrical – between a photographic camera body and a lens. It is confined to cameras where the body allows interchangeable lenses, most the rangefinder camera, single lens reflex type or any movie camera of 16 mm or higher gauge. Lens mounts are used to connect optical components in instrumentation that may not involve a camera, such as the modular components used in optical laboratory prototyping which join via C-mount or T-mount elements. A lens mount may be a bayonet-type, or a breech-lock type. Modern still camera lens mounts are of the bayonet type, because the bayonet mechanism aligns mechanical and electrical features between lens and body. Screw-threaded mounts are fragile and do not align the lens in a reliable rotational position, yet types such as the C-mount interface are still in use for other applications like video cameras and optical instrumentation. Bayonet mounts have a number of tabs around the base of the lens, which fit into appropriately sized recesses in the lens mounting plate on the front of the camera.
The tabs are "keyed" in some way to ensure that the lens is only inserted in one orientation by making one tab a different size. Once inserted the lens is fastened by turning it a small amount, it is locked in place by a spring-loaded pin, which can be operated to remove the lens. Lens mounts of competing manufacturers are always incompatible. In addition to the mechanical and electrical interface variations, the flange focal distance from the lens mount to the film or sensor can be different. Many allege that these incompatibilities are due to the desire of manufacturers to "lock in" consumers to their brand. In movie cameras, the two most popular mounts in current usage on professional digital cinematography cameras are Arri's PL-mount and Panavision's PV-mount; the PL-Mount is used both on Arri and RED digital cinematography cameras, which as of 2012 are the most used cameras for films shot in digital. The Panavision mounts are used with Panavision lenses, thus are only available on Panaflex cameras or third-party cameras "Panavised" by a Panavision rental house, whereas the PL-mount style is favored with most other cameras and cine lens manufacturers.
Both of these mounts are held in place with locating pins and friction locking rings. Other mounts which are now historical or a minority in relation to current practices are listed below. For small camera modules, used in e.g. CCTV systems and machine vision, a range of metric thread mounts exists; the smallest ones can be found in e.g. cellphones and endoscopes. The most common by far is the M12x0.5, followed by M8x0.5 and M10x0.5. M4.2x0.2 M4.6x0.25 M5x0.35 M5.5x0.35 M6x0.35 M6.4x0.25 M7x0.35 M8x0.35 M8x0.5 M9x0.5 M10x0.5 M12x0.5 The axial adjustment range for focusing Ultra wide angle lenses and some Wide-angle lenses in large format cameras is very small. So some manufacturers offered special focusing lens mounts, so-called wide-angle focusing accessories for their cameras. With such a device, the lens could be focused without moving the entire front standard. Secondary lens refers to a multi-element lens mounted either in front of a camera's primary lens, or in between the camera body and the primary lens.
SLR camera & interchangeable-lens manufacturers offer lens accessories like extension tubes and secondary lenses like teleconverters, which mount in between the camera body and the primary lens, both using and providing a primary lens mount. Various lensmakers offer optical accessories that mount in front of the lens. Canon PowerShot A and Canon PowerShot G cameras have a built-in or non-interchangeable primary lens, Canon has "conversion tube" accessories available for some Canon PowerShot camera models which provide either a 52mm or 58mm "accessory/filter" screw thread. Canon's close-up, wide-, tele-conversion lenses have 2, 3, 4-element lenses so they are multi-element lenses and not diopter "filters". Lens mount. A lens can be adapted to a camera body with a smaller flange focal distance by adding space between the camera and the lens; when attempting to adapt a lens to a camera body with a larger flange focal distance, the adapter must include a secondary lens in order to compensate. This has the side effect of decreasing the amount of light that reaches the sensor, as well as adding a crop factor to the lens.
Without the secondary lens, these adapters will function as an extension tube and will not be able to focus to infinity. ISO metric screw thread Lens board ^ A: The authoritative normative source for 4/3 standards information is Four-Thirds. Org and not 3rd-party reviews.4/3's published facts: "Size of the 4/3-type Sensor: The standard diagonal length of the sensor is 21.63 millimetres. It is half that of 35-mm film format The image circle of the interchangeable lens is specified based on this diagonal length. Th
Mirrorless interchangeable-lens camera
A mirrorless interchangeable lens camera simply mirrorless camera, sometimes called EVIL features a single, removable lens and uses a digital display system rather than an optical viewfinder. The word "mirrorless" indicates that the camera does not have an optical mirror or an optical viewfinder like a conventional single-lens reflex camera, but an electronic viewfinder which displays what the camera image sensor sees. In many mirrorless models, the mechanical shutter remains. Like an SLR, an interchangeable lens mirrorless camera accepts any of a series of interchangeable lenses compatible with the lens mount of that camera. A mirrorless interchangeable lens camera is an alternative to the digital single-lens reflex camera. Compared to DSLR cameras, mirrorless cameras are mechanically simpler and are smaller and quieter due to the elimination of the moving mirror. While nearly all mirrorless cameras still have a mechanical shutter, many have an electronic shutter, which eliminates any sound.
Additionally the lack of a moving mirror reduces vibration that can result in blurred images from camera shake. Until mirrorless cameras were somewhat challenged to provide an electronic viewfinder with the clarity low-time-lag responsiveness of the optical viewfinders used on DSLRs; the fact that the image from the lens is always projected onto the image sensor allows for features that are only available in DSLRs when their mirror is locked up into "live view" mode. This includes the ability to show a focus-peaking display, zebra patterning, face or eye tracking. Moreover, the electronic viewfinder can provide live depth of field preview, can show a poorly-illuminated subject how it would look with correct exposure in real time, is easier to view the results of an exposure in bright sunlight. With the latest phase-detect autofocus available on some mirrorless cameras, autofocus speed and accuracy has been shown to be as good as DSLRs, but compared with DSLRs, mirrorless cameras have smaller buffers.
On-sensor auto-focus is free of the adjustment requirements of the indirect focusing system of the DSLR, the latest mirrorless cameras can shoot with phase-detect autofocus at up to 20 frames per second using up to 693 focus points—a number exceeding what is available on any DSLR. Using manual focus with an electronic viewfinder can be assisted by the ability to magnify the subject. In 2013, mirrorless system cameras constituted about five percent of total camera shipments. In 2015, they accounted for 26 percent of system camera sales outside of the Americas, 16 percent within the United States.2004–2008. The first mirrorless camera commercially marketed was the Epson R-D1, followed by the Leica M8; the Micro Four Thirds system, whose first camera was the Panasonic Lumix DMC-G1, was released in Japan in October 2008.2009–2010. The Ricoh GXR had a radically different design; the mirrorless camera featured interchangeable lens units – a sealed unit of a lens and sensor, instead of a normal interchangeable lens.
This design was comparable to but distinct from mirrorless cameras, received mixed reviews due to cost. Following the introduction of the Micro Four Thirds system, several other cameras were released by Panasonic and Olympus, with the Olympus PEN E-P1 being the first mirrorless camera in a compact size; the Samsung NX10 was the first camera in this class not using the Micro Four Thirds system, instead utilizing a new, proprietary lens mount. The Sony Alpha NEX-3 and NEX-5 saw Sony enter the market with a new, proprietary lens mount, though the camera included LA-EA1 and LA-EA2 adapters for the legacy Minolta A-mount. 2011. In June 2011, Pentax announced the'Q' mirrorless interchangeable lens camera and the'Q-mount' lens system; the original Q series featured a smaller 1/2.3 inch 12.4 megapixel CMOS sensor. The Q7, introduced in 2013, has a larger 1/1.7 inch CMOS sensor with the same megapixel count. In September 2011, Nikon announced their Nikon 1 system which consists of the Nikon 1 J1 and Nikon 1 V1 cameras and lenses.
The V1 features an electronic viewfinder. The series includes high-speed mirrorless cameras which, according to Nikon, featured the world's fastest autofocus and the world's fastest continuous shooting speed among all cameras with interchangeable lenses including DSLRs.2012. The Fujifilm X-Pro1, announced in January 2012, was the first non-rangefinder mirrorless with a built-in optical viewfinder, its hybrid viewfinder overlaid electronic information, including shifting frame-lines, to compensate for the parallax effect. Its 2016 successor, the X-Pro2, features an updated version of this viewfinder. Beyond just consumer interest, mirrorless lens systems has created significant interest from camera manufacturers as a possible alternative to high-end camera manufacturing. Mirrorless cameras have fewer moving parts than DSLRs, are more electronic, an advantage to electronic manufacturers, while reducing the advantage that existing camera manufacturers have in precision mechanical engineering. Sony's entry level full frame mirrorless α7 II camera has a 24 megapixel 5 axis stabilised sensor but is more compact and lower in cost than any full frame sensor DSLR.
Canon was the last of the major manufacturer of DSLRs to announce their own mirrorless camera, announcing the Canon EOS M in 2012 wi
Micro Four Thirds system
The Micro Four Thirds system is a standard released by Olympus and Panasonic in 2008, for the design and development of mirrorless interchangeable lens digital cameras and lenses. Camera bodies are available from Blackmagic, DJI, JVC, Olympus, Sharp Corporation, Xiaomi. MFT lenses are produced by Cosina Voigtländer, DJI, Kodak, Olympus, Samyang, Sharp Corporation, Sigma, SLR Magic, Tokina and Xiaomi, amongst others. MFT shares the original image sensor size and specification with the Four Thirds system, designed for DSLRs. Unlike Four Thirds, the MFT system design specification does not provide space for a mirror box and a pentaprism, which facilitates smaller body and lens designs via the shorter flange focal distance of 19.25mm. The short flange distance, when combined with an adapter of proper depth, allows MFT bodies to use any lens made for a camera with a flange distance larger than 19.25mm. Still-camera lenses produced by Canon, Minolta, Nikon and Zeiss have all been adapted for MFT use - as well as lenses produced for cinema, e.g. PL mount or C mount.
For comparison of the original Four Thirds with competing DSLR system see Four Thirds system#Advantages and other considerations Compared to most digital compact cameras and many bridge cameras, MFT cameras have better, larger sensors, interchangeable lenses. They provide far greater control over depth-of-field than compact cameras. There are many lenses available. On top of this, a large number of other lenses can be fitted using an adapter. Different lenses yield greater creative possibilities. However, Micro Four Thirds cameras tend to be larger and more expensive than compact cameras. Compared to most digital SLRs, the Micro Four Thirds system is lighter. However, their sensors are smaller than full-frame or APS-C systems; as such, they may produce noisier/grainier images in low light conditions when compared with contemporary cameras with larger sensors. Unlike DSLRs, which use an optical viewfinder, Micro Four Thirds cameras use an electronic viewfinder. Resolutions and refresh speeds on these EVF displays were compared negatively to optical viewfinders, but today's EVF systems are faster and much higher resolution than the original displays.
Micro Four Thirds cameras always afford a greater depth-of-field than SLRs when shooting at the same focal length and aperture, but it is more difficult to design a wide-aperture lens for Micro Four Thirds. Original Micro Four Thirds cameras used a contrast-detection autofocus system, slower than the phase-detect autofocus, standard on DSLRs. To this day most Micro Four Thirds cameras continue to use a contrast-based focussing system. Although some current models, such as the Olympus OM-D E-M1 Mark II, feature a hybrid phase-detect/contrast detect system, Panasonic Lumix cameras have continued to use a contrast-based system called DFD. Both systems today provide focussing speeds to rival or surpass many current DSLRs; the image sensor of Four Thirds and MFT measures 18 mm × 13.5 mm, with an imaging area of 17.3 mm × 13.0 mm, comparable to the frame size of 110 film. Its area, ca. 220 mm², is 30% less than the quasi-APS-C sensors used in other manufacturers' DSLRs. The Four Thirds system uses a 4:3 image aspect ratio, like compact digital cameras.
In comparison, DSLRs adhere to the 3:2 aspect ratio of the traditional 35 mm format. Thus, "Four Thirds" refers to the aspect ratio of the sensor. However, the chip diagonal is shorter than 4/3 of an inch; the MFT design standard specifies multiple aspect ratios: 4:3, 3:2, 16:9, 1:1. With the exception of two MFT cameras, all MFT cameras record in a native 4:3 format image aspect ratio, through cropping of the 4:3 image, can record in 16:9, 3:2 and 1:1 formats. In addition, all current Micro Four Thirds cameras have sensor dust removal technologies; the MFT system design specifies a bayonet type lens mount with a flange focal distance of 19.25 mm. By avoiding internal mirrors, the MFT standard allows a much thinner camera body. Viewing is achieved on all models by live view electronic displays with LCD screens. In addition, some models feature a built-in electronic viewfinder, while others may offer optional detachable electronic viewfinders. An independent optical viewfinder matched to a particular non-zoom prime lens is sometimes an option.
The flange diameter is about 38 mm, 6 mm less than that of the Four Thirds system. Electrically, MFT uses an 11-contact connector between lens and camera, adding to the nine contacts in the Four Thirds system design specification. Olympus claims full backward compatibility for many of its existing Four Thirds lenses on MFT bodies, using a purpose built adapter with both mechanical and electrical interfaces; the shallow but wide MFT lens mount allows the use of existing lenses including Leica M, Leica R, Olympus OM system lenses, via Panasonic and Olympus adapters. Aftermarket adapters include Leica Screw Mount, Contax G, C mount, Arri PL mount, Canon and Pentax, amongst others. In fact any still camera, movie or video camera interchangeable lens that has a flange focal distance greater than or marginally less than 20 mm can be used on MFT bodies vi
Victor Hasselblad AB is a Swedish manufacturer of medium-format cameras, photographic equipment and image scanners based in Gothenburg, Sweden. The company is best known for the classic medium-format cameras it has produced since World War II; the most famous use of the Hasselblad camera was during the Apollo program missions when humans first landed on the Moon. All of the still photographs taken during these missions used modified Hasselblad cameras. Hasselblad only produces about 10,000 cameras a year out of a small three story building; the company was established in 1841 in Gothenburg, Sweden, by Fritz Wiktor Hasselblad, as a trading company, F. W. Hasselblad and Co; the founder's son, Arvid Viktor Hasselblad, was interested in photography and started the photographic division of the company. Hasselblad's corporate website quotes him as saying, "I don’t think that we will earn much money on this, but at least it will allow us to take pictures for free."In 1877, Arvid Hasselblad commissioned the construction of Hasselblad's long-time headquarters building, in use until 2002.
While on honeymoon, Arvid Hasselblad met founder of Eastman Kodak. In 1888, Hasselblad became the sole Swedish distributor of Eastman's products; the business was so successful that in 1908, the photographic operations were spun off into their own corporation, Fotografiska AB. Operations included a nationwide network of shops and photo labs. Management of the company passed to Karl Erik Hasselblad, Arvid's son. Karl Erik wanted his son, Victor Hasselblad, to have a wide understanding of the camera business, sent him to Dresden, Germany the world center of the optics industry, at age 18. Victor spent the next several years studying and working in various photography related endeavors in Europe and the US, including Rochester, New York, with George Eastman, before returning to work at the family business. Due to disputes within the family with his father, Victor left the business and in 1937 started his own photo store and lab in Gothenburg, Victor Foto. During World War II, the Swedish military captured a functioning German aerial surveillance camera from a downed German plane.
This was a Handkammer HK 12.5 cm/7x9, which bore the codename GXN and the military account number Fl.38510. The Swedish government realised the strategic advantage of developing an aerial camera for their own use, in the spring of 1940 approached Victor Hasselblad to help create one. In April 1940, Victor Hasselblad established a camera workshop in Gothenburg called Ross AB in a shed at an automobile shop, working in the evenings in cooperation with a mechanic from the shop and his brother, began designing the HK7 camera. By late 1941, the operation had over 20 employees and the Swedish Air Force asked for another camera, one which would have a larger negative and could be permanently mounted to an aircraft; this model was the SKa4. Between 1941 and 1945, Hasselblad delivered 342 cameras to the Swedish military. In 1942, Karl Erik Hasselblad died and Victor took control of the family business. During the war, in addition to the military cameras, Hasselblad produced watch and clock parts, over 95,000 by the war's end.
After the war and clock production continued, other machine work was carried out, including producing a slide projector and supplying parts for Saab automobiles. Victor Hasselblad's real ambition was to make high-quality civilian cameras. In 1945–1946, the first design drawings and wooden models were made for a camera to be called the Rossex. An internal design competition was held for elements of the camera. In 1948, the camera known as the 1600 F was released; the new design was complex, many small improvements were needed to create a reliable product. Only around 50 units were produced in 1949, 220 in 1950, of what collectors have now designated the Series One camera; the Series Two versions of the 1600 F as many as 3300 made from 1950 to 1953, were more reliable but still subject to frequent repairs, with many units having been cannibalized or modified by the factory. The biggest problem was its shutter, a focal-plane shutter, hard to keep accurate. Using 120 size film it was formatted to a square 6 cm x 6 cm or 2 & ¼ by 2 & ¼ inches which meant there was no more need to turn the camera on its side.
In 1954, they mated the groundbreaking new 38mm Biogon lens designed by Dr. Bertele of Zeiss to a shallow non-reflex body to produce the SWA. Though a specialty product not intended to sell in large numbers, the SWA was an impressive achievement, derivatives were sold for decades. Hasselblad took their two products to the 1954 photokina trade show in Germany, word began to spread. In 1953, a much-improved camera, the 1000 F was released, it too had a focal-plane shutter which led to its final replacement by the 500 C but nonetheless provided a big leg up in the medium format. It had a fine 200mm f4 Sonnar sport lens that made it a great wildlife camera. Lenses ranged from a 60mm Distagon, standard 80mm Planar, on up to the 200 mm. In December 1954, the 1000 F camera received a rave review from the influential American photography magazine, Modern Photography, they put over 500 rolls of film through their test unit, intentionally dropped it twice, it continued to function. But the 1000 F had shutter problems and gave way to the lens-mounted, tried-and-true Compur shutter, retaining its focal-plane shutter/curtain only to mask