ক্যামেরার ইতিহাস

ফটোগ্রাফির চেয়ে ক্যামেরার অগ্রগতির ইতিহাস খুজে বের করা সহজ। ক্যামেরা প্রসূত হয়েছে ক্যামেরা অবস্কিউরা থেকে, এবং ফোটোগ্রাফিক প্রযুক্তির পরিবর্তন অনেক প্রজন্মের মাধ্যমে অব্যাহত, এটি দাগেরিওটাইপস, ক্যালটাইপস, শুষ্ক প্লেট, চলচ্চিত্র, এবং বর্তমান দিনে এটি ডিজিটাল ক্যামেরা। ফোটোগ্রাফিক ক্যামেরা অগ্রদূত হিসেবে ক্যামেরা অবস্কিউরা ছিল। ক্যামেরা অবস্কিউরা (ল্যাটিন "অন্ধকার রুম") হলো প্রাকৃতিক অপটিক্যাল প্রপঞ্চ যেটি একটি পর্দার অন্য দিকে একটি দৃশ্যের যখন একটি চিত্র দেখা দেয় (বা উদাহরণস্বরূপ একটি প্রাচীর) এটি ইমেজ পর্দায় একটি ছোট গর্তের মাধ্যমে অভিক্ষিপ্ত ঘটে এবং একটি উল্টানো ইমেজ ফর্ম (বাম থেকে ডানে এবং উলটাইয়া) একটি পৃষ্ঠের বিপরীত দিকে দেখা যায়। এই নীতির প্রাচীনতম জ্ঞাত রেকর্ডের বিবরণ দিয়েছেন হান চীনা দার্শনিক মযি (ca. 470 to ca. 391 BC). মযি বর্তমানে দাবি করেন ক্যামেরা অবস্কিউরা ইমেজ উল্টানো হয় কারণ আলো তার উৎস থেকে সোজা লাইনে ভ্রমণ করে। ১১তম শতাব্দীতে আরব পদার্থবিদ ইবনে আল-হাইসাম (আলহাজেন) পরীক্ষা-নিরীক্ষা সহ একটি অন্ধকার রুমে একটা ছোট ফুটো দিয়ে আলো দিয়ে, অপটিক্স সম্পর্কে খুব প্রভাবশালী বই লিখেছিলেন। একটি খোলা প্রাচীরে একটি লেন্স ব্যবহার করা হয়েছে বা একটি অন্ধকার রুমে বদ্ধ জানালায় ঝিলমিল চিত্র তুলে ধরার জন্য অঙ্কন এইড এর সাহায্যে প্রায় ১৫৫০ পিছনে প্রকল্প চিত্র আঁকা হয়েছে। ১৭তম শতাব্দীর পর থেকে তাঁবু এবং বাক্সে বহনীয় ক্যামেরা অবস্কিউরা ডিভাইসের একটি অঙ্কন এইড হিসাবে ব্যবহার করা হয়। ফোটোগ্রাফিক প্রসেস উদ্ভাবনের পূর্বে তাদের ক্যামেরায় ধারণকৃত ছবি সংরক্ষণ করার কোন উপায় ছিল। নিকটতম ক্যামেরাগুলো রুম মাপের ছিল, যেটাতে এক বা একাধিক মানুষের জন্য জায়গা ছিল; এটি ধীরে ধীরে বিবর্তিত হয়ে আরও সংক্ষিপ্ত মডেলে পরিণত হয়েছে। নিপসে'স এর সময় পোর্টেবল বক্স ক্যামেরা অবস্কিউরা দ্বারা ফোটোগ্রাফির জন্য সহজলভ্য ছিল। ১৬৮৫ সালে সর্বপ্রথম ইয়োহান যাহ্ন একটি ক্যামেরা কল্পনা করেন যেটি ফোটোগ্রাফির জন্য ছোট এবং হালকা হবে যদিও এটা প্রায় ১৫০ বছর আগে একটি অ্যাপ্লিকেশন সম্ভব ছিল। আনুমানিক ১৮১৬ সালে নিসেফর নিপসে প্রথম সফলভাবে একটি ক্যামেরা ইমেজ তৈরি করেছিলেন, তার নিজের তৈরি একটি খুব ছোট ক্যামেরা এবং কাগজ এক টুকরা সিলভার ক্লোরাইড, যা অন্ধকারে এটি আলো দেখার সুযোগ করে দেয়। অবশিষ্ট অপ্রভাবিত সিলভার ক্লোরাইড সরানো নিপসে এর পরিচিত ছিল, তাই আলোকচিত্র স্থায়ী ছিল না, অবশেষে সম্পূর্ণরূপে সামগ্রিক এক্সপোজার দ্বারা অন্ধকার করা হয়েছে এটা দেখার জন্য প্রয়োজনীয় আলো প্রয়োজন। মধ্য-১৮২০s এর মধ্যে, নিপস একটি সহচরী কাঠের বাক্স ক্যামেরা ব্যবহার করতেন যেটা প্যারিসের অধিবাসী ডাক্তার চার্লস ও ভিনসেন্ট অশ্বারোহী সৈনিক দ্বারা তৈরি যারা ফটোগ্রাফি নিয়ে পরীক্ষা করতেন যা উপরিভাগে ক্রমে লেপা যিহূদিয়ার বিটুমিন সহ। বিটুমিন ধীরে ধীরে ইমেজ উজ্জ্বল এলাকায় কঠিনীভূত হয়। অকঠিনীভূত বিটুমিন তারপর দূরে বিলুপ্ত করা হয়। সেই ফটোগ্রাফ এখনও বেঁচে আছে। ১৮৩৩ সালে নিপস এর মৃত্যুর পর, তার সহকর্মী লুই দাগুয়েরের পরীক্ষা নিরীক্ষা অব্যাহত রাখেন এবং ১৮৩৭ সালে প্রথম ব্যবহারিক ফটোগ্রাফিক পদ্ধতি তৈরি করেছে, যার তিনি দাগেরোটাইপ নাম দেন এবং যা ১৮৩৯ প্রকাশ্যে উন্মোচন করা হয়।. দাগুয়েরে সিলভার আয়োডাইড এর আলোক সংবেদনশীল একটি লেপ দিতে আয়োডিন বাষ্প এর সঙ্গে তামার একটি রূপালী প্রলেপ শীট দেন। ক্যামেরা প্রকাশের পর, ছবি পারদ বাষ্প দ্বারা বিকশিত করা হয় এবং সাধারণ লবণের (সোডিয়াম ক্লোরাইড) একটা শক্তিশালী সমাধান করা হয়। Henry Fox Talbot perfected a different process, the ক্যালোটাইপ, in 1840. As commercialized, both processes used very simple cameras consisting of two nested boxes. The rear box had a removable ground glass screen and could slide in and out to adjust the focus. After focusing, the ground glass was replaced with a light-tight holder containing the sensitized plate or paper and the lens was capped. Then the photographer opened the front cover of the holder, uncapped the lens, and counted off as many minutes as the lighting conditions seemed to require before replacing the cap and closing the holder. Despite this mechanical simplicity, high-quality achromatic lenses were standard. Collodion dry plates had been available since 1857, thanks to the work of Désiré van Monckhoven, but it was not until the invention of the gelatin dry plate in 1871 by Richard Leach Maddox that the wet plate process could be rivaled in quality and speed. The 1878 discovery that heat-ripening a gelatin emulsion greatly increased its sensitivity finally made so-called "instantaneous" snapshot exposures practical. For the first time, a tripod or other support was no longer an absolute necessity. With daylight and a fast plate or film, a small camera could be hand-held while taking the picture. The ranks of amateur photographers swelled and informal "candid" portraits became popular. There was a proliferation of camera designs, from single- and twin-lens reflexes to large and bulky field cameras, simple box cameras, and even "detective cameras" disguised as pocket watches, hats, or other objects. The short exposure times that made candid photography possible also necessitated another innovation, the mechanical shutter. The very first shutters were separate accessories, though built-in shutters were common by the end of the 19th century. The use of photographic film was pioneered by George Eastman, who started manufacturing paper film in 1885 before switching to celluloid in 1888-1889. His first camera, which he called the "Kodak," was first offered for sale in 1888. It was a very simple box camera with a fixed-focus lens and single shutter speed, which along with its relatively low price appealed to the average consumer. The Kodak came pre-loaded with enough film for 100 exposures and needed to be sent back to the factory for processing and reloading when the roll was finished. By the end of the 19th century Eastman had expanded his lineup to several models including both box and folding cameras. In 1900, Eastman took mass-market photography one step further with the Brownie, a simple and very inexpensive box camera that introduced the concept of the snapshot. The Brownie was extremely popular and various models remained on sale until the 1960s. Film also allowed the movie camera to develop from an expensive toy to a practical commercial tool. Despite the advances in low-cost photography made possible by Eastman, plate cameras still offered higher-quality prints and remained popular well into the 20th century. To compete with rollfilm cameras, which offered a larger number of exposures per loading, many inexpensive plate cameras from this era were equipped with magazines to hold several plates at once. Special backs for plate cameras allowing them to use film packs or rollfilm were also available, as were backs that enabled rollfilm cameras to use plates. Except for a few special types such as Schmidt cameras, most professional astrographs continued to use plates until the end of the 20th century when electronic photography replaced them. A number of manufacturers started to use 35mm film for still photography between 1905 and 1913. The first 35mm cameras available to the public, and reaching significant numbers in sales were the Tourist Multiple, in 1913, and the Simplex, in 1914. [তথ্যসূত্র প্রয়োজন] Oskar Barnack, who was in charge of research and development at Leitz, decided to investigate using 35 mm cine film for still cameras while attempting to build a compact camera capable of making high-quality enlargements. He built his prototype 35 mm camera (Ur-Leica) around 1913, though further development was delayed for several years by World War I. It wasn't until after World War I that Leica commercialized their first 35mm Cameras. Leitz test-marketed the design between 1923 and 1924, receiving enough positive feedback that the camera was put into production as the Leica I (for Leitz camera) in 1925. The Leica's immediate popularity spawned a number of competitors, most notably the Contax (introduced in 1932), and cemented the position of 35 mm as the format of choice for high-end compact cameras. Kodak got into the market with the Retina I in 1934, which introduced the 135 cartridge used in all modern 35 mm cameras. Although the Retina was comparatively inexpensive, 35 mm cameras were still out of reach for most people and rollfilm remained the format of choice for mass-market cameras. This changed in 1936 with the introduction of the inexpensive Argus A and to an even greater extent in 1939 with the arrival of the immensely popular Argus C3. Although the cheapest cameras still used rollfilm, 35 mm film had come to dominate the market by the time the C3 was discontinued in 1966. The fledgling Japanese camera industry began to take off in 1936 with the Canon 35 mm rangefinder, an improved version of the 1933 Kwanon prototype. Japanese cameras would begin to become popular in the West after Korean War veterans and soldiers stationed in Japan brought them back to the United States and elsewhere. The first practical reflex camera was the Franke & Heidecke Rolleiflex medium format TLR of 1928. Though both single- and twin-lens reflex cameras had been available for decades, they were too bulky to achieve much popularity. The Rolleiflex, however, was sufficiently compact to achieve widespread popularity and the medium-format TLR design became popular for both high- and low-end cameras. A similar revolution in SLR design began in 1933 with the introduction of the Ihagee Exakta, a compact SLR which used 127 rollfilm. This was followed three years later by the first Western SLR to use 135 film, the Kine Exakta (World's first true 35mm SLR was Soviet "Sport" camera, marketed several months before Kine Exakta, though "Sport" used its own film cartridge). The 35mm SLR design gained immediate popularity and there was an explosion of new models and innovative features after World War II. There were also a few 35mm TLRs, the best-known of which was the Contaflex of 1935, but for the most part these met with little success. The first major post-war SLR innovation was the eye-level viewfinder, which first appeared on the Hungarian Duflex in 1947 and was refined in 1948 with the Contax S, the first camera to use a pentaprism. Prior to this, all SLRs were equipped with waist-level focusing screens. The Duflex was also the first SLR with an instant-return mirror, which prevented the viewfinder from being blacked out after each exposure. This same time period also saw the introduction of the Hasselblad 1600F, which set the standard for medium format SLRs for decades. In 1952 the Asahi Optical Company (which later became well known for its Pentax cameras) introduced the first Japanese SLR using 135 film, the Asahiflex. Several other Japanese camera makers also entered the SLR market in the 1950s, including Canon, Yashica, and Nikon. Nikon's entry, the Nikon F, had a full line of interchangeable components and accessories and is generally regarded as the first Japanese system camera. It was the F, along with the earlier S series of rangefinder cameras, that helped establish Nikon's reputation as a maker of professional-quality equipment. While conventional cameras were becoming more refined and sophisticated, an entirely new type of camera appeared on the market in 1948. This was the Polaroid Model 95, the world's first viable instant-picture camera. Known as a Land Camera after its inventor, Edwin Land, the Model 95 used a patented chemical process to produce finished positive prints from the exposed negatives in under a minute. The Land Camera caught on despite its relatively high price and the Polaroid lineup had expanded to dozens of models by the 1960s. The first Polaroid camera aimed at the popular market, the Model 20 Swinger of 1965, was a huge success and remains one of the top-selling cameras of all time. The first camera to feature automatic exposure was the selenium light meter-equipped, fully automatic Super Kodak Six-20 pack of 1938, but its extremely high price (for the time) of $225 ($৪০৮৭ in present terms) kept it from achieving any degree of success. By the 1960s, however, low-cost electronic components were commonplace and cameras equipped with light meters and automatic exposure systems became increasingly widespread. The next technological advance came in 1960, when the German Mec 16 SB subminiature became the first camera to place the light meter behind the lens for more accurate metering. However, through-the-lens metering ultimately became a feature more commonly found on SLRs than other types of camera; the first SLR equipped with a TTL system was the Topcon RE Super of 1962. Digital cameras differ from their analog predecessors primarily in that they do not use film, but capture and save photographs on digital memory cards or internal storage instead. Their low operating costs have relegated chemical cameras to niche markets. Digital cameras now include wireless communication capabilities (for example Wi-Fi or Bluetooth) to transfer, print or share photos, and are commonly found on mobile phones. The concept of digitizing images on scanners, and the concept of digitizing video signals, predate the concept of making still pictures by digitizing signals from an array of discrete sensor elements. Early spy satellites used the extremely complex and expensive method of de-orbit and airborne retrieval of film canisters. Technology was pushed to skip these steps through the use of in-satellite developing and electronic scanning of the film for direct transmission to the ground. The amount of film was still a major limitation, and this was overcome and greatly simplified by the push to develop an electronic image capturing array that could be used instead of film. The first electronic imaging satellite was the KH-11 launched by the NRO in late 1976. It had a charge-coupled device (CCD) array with a resolution of 800 x 800 pixels (0.64 megapixels). At Philips Labs in New York, Edward Stupp, Pieter Cath and Zsolt Szilagyi filed for a patent on "All Solid State Radiation Imagers" on 6 September 1968 and constructed a flat-screen target for receiving and storing an optical image on a matrix composed of an array of photodiodes connected to a capacitor to form an array of two terminal devices connected in rows and columns. Their US patent was granted on 10 November 1970. Texas Instruments engineer Willis Adcock designed a filmless camera that was not digital and applied for a patent in 1972, but it is not known whether it was ever built. The Cromemco CYCLOPS introduced as a hobbyist construction project in 1975 was the first digital camera to be interfaced to a microcomputer. The first recorded attempt at building a self-contained digital camera was in 1975 by Steven Sasson, an engineer at Eastman Kodak. It used the then-new solid-state CCD image sensor chips developed by Fairchild Semiconductor in 1973. The camera weighed 8 pounds (3.6 kg), recorded black and white images to a compact cassette tape, had a resolution of 0.01 megapixels (10,000 pixels), and took 23 seconds to capture its first image in December 1975. The prototype camera was a technical exercise, not intended for production. Handheld electronic cameras, in the sense of a device meant to be carried and used like a handheld film camera, appeared in 1981 with the demonstration of the Sony Mavica (Magnetic Video Camera). This is not to be confused with the later cameras by Sony that also bore the Mavica name. This was an analog camera, in that it recorded pixel signals continuously, as videotape machines did, without converting them to discrete levels; it recorded television-like signals to a 2 × 2 inch "video floppy". In essence it was a video movie camera that recorded single frames, 50 per disk in field mode and 25 per disk in frame mode. The image quality was considered equal to that of then-current televisions. Analog electronic cameras do not appear to have reached the market until 1986 with the Canon RC-701. Canon demonstrated a prototype of this model at the 1984 Summer Olympics, printing the images in the Yomiuri Shinbun, a Japanese newspaper. In the United States, the first publication to use these cameras for real reportage was USA Today, in its coverage of World Series baseball. Several factors held back the widespread adoption of analog cameras; the cost (upwards of $20,000), poor image quality compared to film, and the lack of quality affordable printers. Capturing and printing an image originally required access to equipment such as a frame grabber, which was beyond the reach of the average consumer. The "video floppy" disks later had several reader devices available for viewing on a screen, but were never standardized as a computer drive. The early adopters tended to be in the news media, where the cost was negated by the utility and the ability to transmit images by telephone lines. The poor image quality was offset by the low resolution of newspaper graphics. This capability to transmit images without a satellite link was useful during the Tiananmen Square protests of 1989 and the first Gulf War in 1991. US government agencies also took a strong interest in the still video concept, notably the US Navy for use as a real time air-to-sea surveillance system. The first analog electronic camera marketed to consumers may have been the Casio VS-101 in 1987. A notable analog camera produced the same year was the Nikon QV-1000C, designed as a press camera and not offered for sale to general users, which sold only a few hundred units. It recorded images in greyscale, and the quality in newspaper print was equal to film cameras. In appearance it closely resembled a modern digital single-lens reflex camera. Images were stored on video floppy disks. Silicon Film, a proposed digital sensor cartridge for film cameras that would allow 35 mm cameras to take digital photographs without modification was announced in late 1998. Silicon Film was to work like a roll of 35 mm film, with a 1.3 megapixel sensor behind the lens and a battery and storage unit fitting in the film holder in the camera. The product, which was never released, became increasingly obsolete due to improvements in digital camera technology and affordability. Silicon Films' parent company filed for bankruptcy in 2001. By the late 1980s, the technology required to produce truly commercial digital cameras existed. The first true portable digital camera that recorded images as a computerized file was likely the Fuji DS-1P of 1988, which recorded to a 2 MB SRAM memory card that used a battery to keep the data in memory. This camera was never marketed to the public. The first digital camera of any kind ever sold commercially was possibly the MegaVision Tessera in 1987 though there is not extensive documentation of its sale known. The first portable digital camera that was actually marketed commercially was sold in December 1989 in Japan, the DS-X by Fuji The first commercially available portable digital camera in the United States was the Dycam Model 1, first shipped in November 1990. It was originally a commercial failure because it was black and white, low in resolution, and cost nearly $1,000 (about $2000 in 2014). It later saw modest success when it was re-sold as the Logitech Fotoman in 1992. It used a CCD image sensor, stored pictures digitally, and connected directly to a computer for download. In 1991, Kodak brought to market the Kodak DCS (Kodak Digital Camera System), the beginning of a long line of professional Kodak DCS SLR cameras that were based in part on film bodies, often Nikons. It used a 1.3 megapixel sensor, had a bulky external digital storage system and was priced at $13,000. At the arrival of the Kodak DCS-200, the Kodak DCS was dubbed Kodak DCS-100. The move to digital formats was helped by the formation of the first JPEG and MPEG standards in 1988, which allowed image and video files to be compressed for storage. The first consumer camera with a liquid crystal display on the back was the Casio QV-10 developed by a team led by Hiroyuki Suetaka in 1995. The first camera to use CompactFlash was the Kodak DC-25 in 1996.[তথ্যসূত্র প্রয়োজন]. The first camera that offered the ability to record video clips may have been the Ricoh RDC-1 in 1995. In 1995 Minolta introduced the RD-175, which was based on the Minolta 500si SLR with a splitter and three independent CCDs. This combination delivered 1.75M pixels. The benefit of using an SLR base was the ability to use any existing Minolta AF mount lens. 1999 saw the introduction of the Nikon D1, a 2.74 megapixel camera that was the first digital SLR developed entirely from the ground up by a major manufacturer, and at a cost of under $6,000 at introduction was affordable by professional photographers and high-end consumers. This camera also used Nikon F-mount lenses, which meant film photographers could use many of the same lenses they already owned. Digital camera sales continued to flourish, driven by technology advances. The digital market segmented into different categories, Compact Digital Still Cameras, Bridge Cameras, Mirrorless Compacts and Digital SLRs. One of the major technology advances was the development of CMOS sensors, which helped drive sensor costs low enough to enable the widespread adoption of camera phones. Since 2003, digital cameras have outsold film cameras and Kodak announced in January 2004 that they would no longer sell Kodak-branded film cameras in the developed world - and 2012 filed for bankruptcy after struggling to adapt to the changing industry. Smartphones now routinely include high resolution digital cameras. Single-lens reflex camera Digital camera History of photography Photographic lens design Movie camera Notes Kosinski Dorothy, The Artist and the Camera, Degas to Picasso. New Haven: Yale University Press,1999. p.25 Wade, John (১৯৭৯)। A Short History of the Camera। Watford: Fountain Press। আইএসবিএন 0-85242-640-2।  1634–1699: McCusker, J. J. (১৯৯৭)। How Much Is That in Real Money? A Historical Price Index for Use as a Deflator of Money Values in the Economy of the United States: Addenda et Corrigenda (পিডিএফ)। American Antiquarian Society। উদ্ধৃতি টেমপ্লেট ইংরেজি প্যারামিটার ব্যবহার করেছে (link) 1700–1799: McCusker, J. J. (১৯৯২)। How Much Is That in Real Money? A Historical Price Index for Use as a Deflator of Money Values in the Economy of the United States (পিডিএফ)। American Antiquarian Society। উদ্ধৃতি টেমপ্লেট ইংরেজি প্যারামিটার ব্যবহার করেছে (link) 1800–present: Federal Reserve Bank of Minneapolis। "Consumer Price Index (estimate) 1800–"। সংগ্রহের তারিখ এপ্রিল ১৬, ২০২২। উদ্ধৃতি টেমপ্লেট ইংরেজি প্যারামিটার ব্যবহার করেছে (link) globalsecurity.org – KH-11 KENNAN, 24 April 2007 US 3540011  US 4057830  and US 4163256  were filed in 1972 but were only later awarded in 1976 and 1977. "1970s"। সংগ্রহের তারিখ ১৫ জুন ২০০৮।  Walker, Terry; Garland, Harry; Melen, Roger (ফেব্রুয়ারি ১৯৭৫)। "Build Cyclops"। Popular Electronics। Ziff Davis। 7 (2): 27–31।  "Digital Photography Milestones from Kodak"। Women in Photography International। সংগ্রহের তারিখ ১৭ সেপ্টেম্বর ২০০৭।  "Kodak blog: We Had No Idea"। ২৯ মে ২০১০ তারিখে মূল থেকে আর্কাইভ করা। সংগ্রহের তারিখ ১৩ ডিসেম্বর ২০১৮।  Michael R. Peres (২০০৭)। The Focal Encyclopedia of Photography (4th সংস্করণ)। Focal Press। আইএসবিএন 0-240-80740-5।  Kenji Toyoda (২০০৬)। "Digital Still Cameras at a Glance"। Junichi Nakamura। Image sensors and signal processing for digital still cameras। CRC Press। পৃষ্ঠা 5। আইএসবিএন 978-0-8493-3545-7।  Askey, Phil (২০০১)। "Silicon Film – vaporized-ware"। সংগ্রহের তারিখ ২০ ফেব্রুয়ারি ২০০৮।  "MegaVision Professional Camera Backs"। ১৪ জুলাই ২০১৭ তারিখে মূল থেকে আর্কাইভ করা। সংগ্রহের তারিখ ২২ মার্চ ২০১৭।  1988[স্থায়ীভাবে অকার্যকর সংযোগ] "Digital cameras, the next wave. (Electronic Imaging Issue; includes related articles)"। ৩ মে ২০১৪ তারিখে মূল থেকে আর্কাইভ করা। সংগ্রহের তারিখ ২২ মার্চ ২০১৭।  অজানা প্যারামিটার |1= উপেক্ষা করা হয়েছে (সাহায্য) InfoWorld - Google Books "1990"। digicammuseum.com। সংগ্রহের তারিখ ১৭ সেপ্টেম্বর ২০০৭। [স্থায়ীভাবে অকার্যকর সংযোগ] "Dycam Model 1: The world's first consumer digital still camera"। DigiBarn computer museum।  Carolyn Said, "DYCAM Model 1: The first portable Digital Still Camera", MacWeek, vol. 4, No. 35, 16 Oct. 1990, p. 34. Digital outsells film, but film still king to some | Macworld Smith, Tony (২০০৪-০১-২০)। "Kodak to drop 35mm cameras in Europe, US"। The Register। সংগ্রহের তারিখ ২০০৭-০৪-০৩।  "Eastman Kodak Files for Bankruptcy"। The New York Times। ২০১২-০১-১৯।  http://www.digicammuseum.com/en/ ওয়েব্যাক মেশিনে আর্কাইভকৃত ১৬ ফেব্রুয়ারি ২০১৭ তারিখে Digital Camera Museum with history section